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Terlizzi V, Farrell PM. Update on advances in cystic fibrosis towards a cure and implications for primary care clinicians. Curr Probl Pediatr Adolesc Health Care 2024:101637. [PMID: 38811287 DOI: 10.1016/j.cppeds.2024.101637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
During the past quarter century, the diagnosis and treatment of cystic fibrosis (CF) have been transformed by molecular sciences that initiated a new era with discovery of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The knowledge gained from that breakthrough has had dramatic clinical impact. Although once a diagnostic dilemma with long delays, preventable deaths, and irreversible pathology, CF can now be routinely diagnosed shortly after birth through newborn screening programs. This strategy of pre-symptomatic identification has eliminated the common diagnostic "odyssey" that was a failure of the healthcare delivery system causing psychologically traumatic experiences for parents. Therapeutic advances of many kinds have culminated in CFTR modulator treatment that can reduce the effects of or even correct the molecular defect in the chloride channel -the basic cause of CF. This astonishing advance has transformed CF care as described fully herein. Despite this impressive progress, there are challenges and controversies in the delivery of care. Issues include how best to achieve high sensitivity newborn screening with acceptable specificity; what course of action is appropriate for children who are identified through the unavoidable incidental findings of screening tests (CFSPID/CRMS cases and heterozygote carriers); how best to ensure genetic counseling; when to initiate the very expensive but life-saving CFTR modulator drugs; how to identify new CFTR modulator drugs for patients with non-responsive CFTR variants; how to adjust other therapeutic modalities; and how to best partner with primary care clinicians. Progress always brings new challenges, and this has been evident worldwide for CF. Consequently, this article summarizes the major advances of recent years along with controversies and describes their implications with an international perspective.
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Affiliation(s)
- Vito Terlizzi
- Department of Pediatric Medicine, Meyer Children's Hospital IRCCS, Cystic Fibrosis Regional Reference Center, Viale Gaetano Pieraccini 24, Florence, Italy
| | - Philip M Farrell
- Departments of Pediatrics and Population Health Sciences, University of Wisconsin School of Medicine and Public Health, Clinical Sciences Center (K4/948), 600 Highland Avenue, Madison, WI 53792, USA.
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Busack LM, Thee S, Liu Y, Allomba C, Ziegahn N, Tosolini A, Pioch CO, Schnorr AN, Fuhlrott BR, Staudacher O, Völler M, Steinke E, Hanitsch LG, Röhmel J, Wahn V, Krüger R, Mall MA, von Bernuth H, Stahl M. Multiple-breath washout to detect lung disease in patients with inborn errors of immunity. ERJ Open Res 2024; 10:01019-2023. [PMID: 38469376 PMCID: PMC10926008 DOI: 10.1183/23120541.01019-2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Accepted: 01/15/2024] [Indexed: 03/13/2024] Open
Abstract
Background Pulmonary manifestations are the major cause of morbidity and mortality in patients with inborn errors of immunity (IEI). New and more sensitive diagnostic methods can potentially lead to earlier recognition and treatment of IEI lung disease and improve outcome. The aim of this study was to compare multiple-breath washout (MBW) and spirometry in patients with IEI and cystic fibrosis (CF) as well as healthy controls (HC) and to evaluate the sensitivity of lung clearance index (LCI) to assess lung disease in IEI. Methods IEI patients (n=114) were recruited from our paediatric and adult immunodeficiency outpatient clinics and compared to age-matched CF patients (n=114) and HC (n=114). MBW measurements and spirometry were performed in the study participants, and MBW testing was repeated after 63-707 days in IEI patients (n=70). Results The LCI was significantly higher in IEI patients than in HC (p<0.001) and significantly lower than in CF patients (p<0.001). The forced expiratory volume in 1 s (FEV1) z-score was significantly lower in IEI patients than in HC (p<0.01) and significantly higher than in CF patients (p<0.01). LCI and FEV1 z-score correlated moderately negatively in the total cohort, the IEI group and the CF group. Nineteen (20.7%) of 92 IEI patients and 35 (33.3%) of 105 CF patients had an elevated LCI but a normal FEV1 z-score. After a median of 364 days, the median LCI of 70 IEI patients increased significantly by 0.2. Conclusion MBW is useful to detect lung disease in IEI and is more sensitive than spirometry.
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Affiliation(s)
- Leonie M. Busack
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Stephanie Thee
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
- Berlin Institute of Health at Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Yvonne Liu
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Christine Allomba
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Niklas Ziegahn
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Apolline Tosolini
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Charlotte O. Pioch
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Alexandra N. Schnorr
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Bent R. Fuhlrott
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Olga Staudacher
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Mirjam Völler
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
- German Center for Lung Research, associated partner site, Berlin, Germany
| | - Eva Steinke
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
- Berlin Institute of Health at Charité – Universitätsmedizin Berlin, Berlin, Germany
- German Center for Lung Research, associated partner site, Berlin, Germany
| | - Leif G. Hanitsch
- Berlin Institute of Health at Charité – Universitätsmedizin Berlin, Berlin, Germany
- Institute of Medical Immunology, Charité – Universitätsmedizin Berlin, Berlin, Germany
- Berlin Center for Regenerative Therapies, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Jobst Röhmel
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
- Berlin Institute of Health at Charité – Universitätsmedizin Berlin, Berlin, Germany
- German Center for Lung Research, associated partner site, Berlin, Germany
| | - Volker Wahn
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Renate Krüger
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Marcus A. Mall
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
- Berlin Institute of Health at Charité – Universitätsmedizin Berlin, Berlin, Germany
- German Center for Lung Research, associated partner site, Berlin, Germany
| | - Horst von Bernuth
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
- Berlin Institute of Health at Charité – Universitätsmedizin Berlin, Berlin, Germany
- Berlin Center for Regenerative Therapies, Charité – Universitätsmedizin Berlin, Berlin, Germany
- Department of Immunology, Labor Berlin-Charité Vivantes GmbH, Berlin, Germany
| | - Mirjam Stahl
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
- Berlin Institute of Health at Charité – Universitätsmedizin Berlin, Berlin, Germany
- German Center for Lung Research, associated partner site, Berlin, Germany
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De Marchis M, Montemitro E, Boni A, Federici A, Di Giovanni D, Cristiani L, Cutrera R, Fiocchi AG. Lung clearance index short-term variability in cystic fibrosis: a pre-post pulmonary exacerbation study. Ital J Pediatr 2024; 50:6. [PMID: 38233941 PMCID: PMC10795345 DOI: 10.1186/s13052-023-01574-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Accepted: 12/26/2023] [Indexed: 01/19/2024] Open
Abstract
BACKGROUND Multiple Breath washout (MBW) represents an important tool to detect early a possible pulmonary exacerbation especially in Cystic Fibrosis (CF) disease. Lung clearance index (LCI) is the most commonly reported multiple breath washout (MBW) index and in the last years was used as management measure for evaluation. Our aim was to analyze clinical utility of LCI index variability in pulmonary exacerbation in CF after intravenous (IV) antibiotic therapy. METHODS A single-center study was conducted at CF Unit of Bambino Gesù Children's Hospital among hospitalized > 3 years patients for pulmonary exacerbations and treated with antibiotic IV treatment for 14 days. MBW and spirometry were evaluated within 72 h of admission to hospital and at the end of hospitalization. Descriptive analysis was conducted and correlations between quantitative variables were investigated. RESULTS Fifty-seven patients (M22/F35) with an average age 18.56 (± 8.54) years were enrolled. LCI2.5 was significantly reduced at the end of antibiotic treatment in both pediatric and adult populations with an average reduction of -6,99%; 37/57 patients denoted an improvement, 20/57 are stable or worsened in LCI2.5 values and 4/57 (7.02%) had a significant deterioration (> 15%) at end of treatment. On the contrary a significative elevation of FEV1 and FVC were found, respectively of + 7,30% and of + 5,46%. A positive good correlection among LCI 2.5 and Scond (rho = + 0,615, p = 0.000) and LCI 2.5 and Sacin (rho = + 0,649, p = 0.000) and a negative strong correlation between FEV1 and LCI 2.5 were found in post treatment period. A similar modification of LCI 2.5 and FEV1 was noticed in both adult and pediatric population. CONCLUSIONS LCI may have a role in the routine clinical care of both adult and pediatric CF patients as a good tool to assess response to IV antibiotic end-therapy in the same way as FEV1.
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Affiliation(s)
- Matteo De Marchis
- Pneumology and Cystic Fibrosis Unit, Bambino Gesù Children's Hospital IRCCS, Rome, Italy.
- University of Magna Graecia of Catanzaro, Calabria, Italy.
| | - Enza Montemitro
- Pneumology and Cystic Fibrosis Unit, Bambino Gesù Children's Hospital IRCCS, Rome, Italy
| | - Alessandra Boni
- Pneumology and Cystic Fibrosis Unit, Bambino Gesù Children's Hospital IRCCS, Rome, Italy
| | - Alessandra Federici
- Pneumology and Cystic Fibrosis Unit, Bambino Gesù Children's Hospital IRCCS, Rome, Italy
| | - Daniele Di Giovanni
- Industrial Engineering Department, University of Rome Tor Vergata, Rome, Italy
- Unicamillus, Saint Camillus International University of Health Sciences, Rome, Italy
| | - Luca Cristiani
- Pneumology and Cystic Fibrosis Unit, Bambino Gesù Children's Hospital IRCCS, Rome, Italy
| | - Renato Cutrera
- Pneumology and Cystic Fibrosis Unit, Bambino Gesù Children's Hospital IRCCS, Rome, Italy
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Marshall H, Voskrebenzev A, Smith LJ, Biancardi AM, Kern AL, Collier GJ, Wielopolski PA, Ciet P, Tiddens HAWM, Vogel‐Claussen J, Wild JM. 129 Xe and Free-Breathing 1 H Ventilation MRI in Patients With Cystic Fibrosis: A Dual-Center Study. J Magn Reson Imaging 2023; 57:1908-1921. [PMID: 36218321 PMCID: PMC10946578 DOI: 10.1002/jmri.28470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 09/26/2022] [Accepted: 09/27/2022] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Free-breathing 1 H ventilation MRI shows promise but only single-center validation has yet been performed against methods which directly image lung ventilation in patients with cystic fibrosis (CF). PURPOSE To investigate the relationship between 129 Xe and 1 H ventilation images using data acquired at two centers. STUDY TYPE Sequence comparison. POPULATION Center 1; 24 patients with CF (12 female) aged 9-47 years. Center 2; 7 patients with CF (6 female) aged 13-18 years, and 6 healthy controls (6 female) aged 21-31 years. Data were acquired in different patients at each center. FIELD STRENGTH/SEQUENCE 1.5 T, 3D steady-state free precession and 2D spoiled gradient echo. ASSESSMENT Subjects were scanned with 129 Xe ventilation and 1 H free-breathing MRI and performed pulmonary function tests. Ventilation defect percent (VDP) was calculated using linear binning and images were visually assessed by H.M., L.J.S., and G.J.C. (10, 5, and 8 years' experience). STATISTICAL TESTS Correlations and linear regression analyses were performed between 129 Xe VDP, 1 H VDP, FEV1 , and LCI. Bland-Altman analysis of 129 Xe VDP and 1 H VDP was carried out. Differences in metrics were assessed using one-way ANOVA or Kruskal-Wallis tests. RESULTS 129 Xe VDP and 1 H VDP correlated strongly with; each other (r = 0.84), FEV1 z-score (129 Xe VDP r = -0.83, 1 H VDP r = -0.80), and LCI (129 Xe VDP r = 0.91, 1 H VDP r = 0.82). Bland-Altman analysis of 129 Xe VDP and 1 H VDP from both centers had a bias of 0.07% and limits of agreement of -16.1% and 16.2%. Linear regression relationships of VDP with FEV1 were not significantly different between 129 Xe and 1 H VDP (P = 0.08), while 129 Xe VDP had a stronger relationship with LCI than 1 H VDP. DATA CONCLUSION 1 H ventilation MRI shows large-scale agreement with 129 Xe ventilation MRI in CF patients with established lung disease but may be less sensitive to subtle ventilation changes in patients with early-stage lung disease. EVIDENCE LEVEL 2 TECHNICAL EFFICACY: Stage 2.
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Affiliation(s)
- Helen Marshall
- POLARIS, Imaging Sciences, Department of Infection, Immunity & Cardiovascular DiseaseUniversity of SheffieldSheffieldUK
| | - Andreas Voskrebenzev
- Institute for Diagnostic and Interventional RadiologyHannover Medical SchoolHannoverGermany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH)German Center for Lung Research (DZL)HannoverGermany
| | - Laurie J. Smith
- POLARIS, Imaging Sciences, Department of Infection, Immunity & Cardiovascular DiseaseUniversity of SheffieldSheffieldUK
| | - Alberto M. Biancardi
- POLARIS, Imaging Sciences, Department of Infection, Immunity & Cardiovascular DiseaseUniversity of SheffieldSheffieldUK
| | - Agilo L. Kern
- Institute for Diagnostic and Interventional RadiologyHannover Medical SchoolHannoverGermany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH)German Center for Lung Research (DZL)HannoverGermany
| | - Guilhem J. Collier
- POLARIS, Imaging Sciences, Department of Infection, Immunity & Cardiovascular DiseaseUniversity of SheffieldSheffieldUK
| | | | - Pierluigi Ciet
- Department of Radiology and Nuclear medicineErasmus MCRotterdamThe Netherlands
- Department of Pediatric Pulmonology and AllergologySophia Children's Hospital, Erasmus MCRotterdamThe Netherlands
| | - Harm A. W. M. Tiddens
- Department of Radiology and Nuclear medicineErasmus MCRotterdamThe Netherlands
- Department of Pediatric Pulmonology and AllergologySophia Children's Hospital, Erasmus MCRotterdamThe Netherlands
| | - Jens Vogel‐Claussen
- Institute for Diagnostic and Interventional RadiologyHannover Medical SchoolHannoverGermany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH)German Center for Lung Research (DZL)HannoverGermany
| | - Jim M. Wild
- POLARIS, Imaging Sciences, Department of Infection, Immunity & Cardiovascular DiseaseUniversity of SheffieldSheffieldUK
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Kooner HK, McIntosh MJ, Matheson AM, Abdelrazek M, Albert MS, Dhaliwal I, Kirby M, Ouriadov A, Santyr GE, Venegas C, Radadia N, Svenningsen S, Nicholson JM, Parraga G. Post-Acute COVID-19 Syndrome: 129Xe MRI Ventilation Defects and Respiratory Outcomes One Year Later. Radiology 2023; 307:e222557. [PMID: 36749209 PMCID: PMC9926501 DOI: 10.1148/radiol.222557] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Background In people with post-acute COVID-19 syndrome (PACS) and normal pulmonary function, 129Xe MRI ventilation defects, abnormal quality-of-life scores, and exercise limitation were reported 3-months after infection; the longitudinal trajectory remains unclear. Purpose To measure and compare pulmonary function, exercise capacity, quality-of-life, and 129Xe MRI ventilation defect percent (VDP) in people with PACS evaluated 3- and 15-months post-infection. Materials and Methods In this prospective study, participants with PACS aged 18-80 years were enrolled between July 2020 and August 2021 from two quaternary care centers. They were evaluated 3-months and 15-months post-infection for: 129Xe MRI VDP, diffusing capacity of the lung for carbon monoxide (DLCO), spirometry, oscillometry, six-minute walk distance (6MWD), and St. George's Respiratory Questionnaire (SGRQ). Differences between time-points were evaluated using paired t-tests. Multivariable models were generated to explain exercise capacity and quality-of-life improvements. Odds ratios (OR) were used to evaluate potential treatment influences. Results Fifty-three participants (mean age, 55 years ±18[SD]; 26 male; 27 female) attended both 3- and 15-month visits and were included in analysis. 129Xe MRI VDP (5.4%, 4.2%; P=.003), forced expiratory volume in 1-second (85%pred, 90%pred; P=.001), DLCO (89%pred, 99%pred; P=.002) and SGRQ (35, 25; P<.001) improved between the 3- and 15-month visit. VDP measured at 3- months post-COVID predicted the change in 6MWD (β=-.643, P=.001) while treatment with respiratory medication at 3-months predicted improved 15-month quality-of-life score (OR=4.0; 95%CI:1.2,13.8, P=.03). Conclusion Pulmonary function, gas-exchange, exercise capacity, quality-of-life, and 129Xe MRI ventilation defect percent (VDP) improved in participants with post-acute COVID-19 syndrome evaluated at 15-months as compared to 3-months post-infection. VDP measured at 3-months post-infection correlated with improved exercise capacity, whilst treatment with respiratory medication was associated with improved quality-of-life score at 15-months post-infection. Clinical Trial Registration: www.clinicaltrials.gov NCT05014516 See also the editorial by Vogel-Claussen in this issue.
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Affiliation(s)
| | | | | | | | | | - Inderdeep Dhaliwal
- Division of Respirology, Department of Medicine, Western University,
London, Canada
| | - Miranda Kirby
- Department of Physics, Toronto Metropolitan University, Toronto,
Canada
| | - Alexei Ouriadov
- Department of Physics and Astronomy, Western University, London,
Canada
| | | | - Carmen Venegas
- Division of Respirology, Department of Medicine, McMaster University
and Firestone Institute for Respiratory Health, St Joseph's Health Care,
Hamilton, Canada
| | - Nisarg Radadia
- Division of Respirology, Department of Medicine, McMaster University
and Firestone Institute for Respiratory Health, St Joseph's Health Care,
Hamilton, Canada
| | - Sarah Svenningsen
- Division of Respirology, Department of Medicine, McMaster University
and Firestone Institute for Respiratory Health, St Joseph's Health Care,
Hamilton, Canada
| | - J Michael Nicholson
- Division of Respirology, Department of Medicine, Western University,
London, Canada
| | - Grace Parraga
- Robarts Research Institute,Department of Medical Biophysics,Department of Medical Imaging, Western University, London,
Canada,Division of Respirology, Department of Medicine, Western University,
London, Canada
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Chan HF, Smith LJ, Biancardi AM, Bray J, Marshall H, Hughes PJC, Collier GJ, Rao M, Norquay G, Swift AJ, Hart K, Cousins M, Watkins WJ, Wild JM, Kotecha S. Image Phenotyping of Preterm-Born Children Using Hyperpolarized 129Xe Lung Magnetic Resonance Imaging and Multiple-Breath Washout. Am J Respir Crit Care Med 2023; 207:89-100. [PMID: 35972833 PMCID: PMC9952860 DOI: 10.1164/rccm.202203-0606oc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 08/16/2022] [Indexed: 02/03/2023] Open
Abstract
Rationale: Preterm birth is associated with low lung function in childhood, but little is known about the lung microstructure in childhood. Objectives: We assessed the differential associations between the historical diagnosis of bronchopulmonary dysplasia (BPD) and current lung function phenotypes on lung ventilation and microstructure in preterm-born children using hyperpolarized 129Xe ventilation and diffusion-weighted magnetic resonance imaging (MRI) and multiple-breath washout (MBW). Methods: Data were available from 63 children (aged 9-13 yr), including 44 born preterm (⩽34 weeks' gestation) and 19 term-born control subjects (⩾37 weeks' gestation). Preterm-born children were classified, using spirometry, as prematurity-associated obstructive lung disease (POLD; FEV1 < lower limit of normal [LLN] and FEV1/FVC < LLN), prematurity-associated preserved ratio of impaired spirometry (FEV1 < LLN and FEV1/FVC ⩾ LLN), preterm-(FEV1 ⩾ LLN) and term-born control subjects, and those with and without BPD. Ventilation heterogeneity metrics were derived from 129Xe ventilation MRI and SF6 MBW. Alveolar microstructural dimensions were derived from 129Xe diffusion-weighted MRI. Measurements and Main Results: 129Xe ventilation defect percentage and ventilation heterogeneity index were significantly increased in preterm-born children with POLD. In contrast, mean 129Xe apparent diffusion coefficient, 129Xe apparent diffusion coefficient interquartile range, and 129Xe mean alveolar dimension interquartile range were significantly increased in preterm-born children with BPD, suggesting changes of alveolar dimensions. MBW metrics were all significantly increased in the POLD group compared with preterm- and term-born control subjects. Linear regression confirmed the differential effects of obstructive disease on ventilation defects and BPD on lung microstructure. Conclusion: We show that ventilation abnormalities are associated with POLD, and BPD in infancy is associated with abnormal lung microstructure.
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Affiliation(s)
- Ho-Fung Chan
- Pulmonary, Lung and Respiratory Imaging Sheffield (POLARIS), Imaging Sciences, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Laurie J. Smith
- Pulmonary, Lung and Respiratory Imaging Sheffield (POLARIS), Imaging Sciences, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Alberto M. Biancardi
- Pulmonary, Lung and Respiratory Imaging Sheffield (POLARIS), Imaging Sciences, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Jody Bray
- Pulmonary, Lung and Respiratory Imaging Sheffield (POLARIS), Imaging Sciences, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Helen Marshall
- Pulmonary, Lung and Respiratory Imaging Sheffield (POLARIS), Imaging Sciences, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Paul J. C. Hughes
- Pulmonary, Lung and Respiratory Imaging Sheffield (POLARIS), Imaging Sciences, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Guilhem J. Collier
- Pulmonary, Lung and Respiratory Imaging Sheffield (POLARIS), Imaging Sciences, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Madhwesha Rao
- Pulmonary, Lung and Respiratory Imaging Sheffield (POLARIS), Imaging Sciences, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Graham Norquay
- Pulmonary, Lung and Respiratory Imaging Sheffield (POLARIS), Imaging Sciences, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Andrew J. Swift
- Pulmonary, Lung and Respiratory Imaging Sheffield (POLARIS), Imaging Sciences, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Kylie Hart
- Department of Child Health, School of Medicine, Cardiff University, Cardiff, United Kingdom
- Neonatal Unit, Cardiff and Vale University Health Board, Cardiff, United Kingdom
| | - Michael Cousins
- Department of Child Health, School of Medicine, Cardiff University, Cardiff, United Kingdom
- Neonatal Unit, Cardiff and Vale University Health Board, Cardiff, United Kingdom
| | - W. John Watkins
- Department of Child Health, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Jim M. Wild
- Pulmonary, Lung and Respiratory Imaging Sheffield (POLARIS), Imaging Sciences, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Sailesh Kotecha
- Department of Child Health, School of Medicine, Cardiff University, Cardiff, United Kingdom
- Neonatal Unit, Cardiff and Vale University Health Board, Cardiff, United Kingdom
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7
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Britto CJ, Ratjen F, Clancy JP. Emerging Approaches to Monitor and Modify Care in the Era of Cystic Fibrosis Transmembrane Conductance Regulators. Clin Chest Med 2022; 43:631-646. [PMID: 36344071 DOI: 10.1016/j.ccm.2022.06.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
As we characterize the clinical benefits of highly effective modulator therapy (HEMT) in the cystic fibrosis (CF) population, our paradigm for treating and monitoring disease continues to evolve. More sensitive approaches are necessary to detect early disease and clinical progression. This article reviews evolving strategies to assess disease control and progression in the HEMT era. This article also explores developments in pulmonary function monitoring, advanced respiratory imaging, tools for the collection of patient-reported outcomes, and their application to profile individual responses, guide therapeutic decisions, and improve the quality of life of people with CF.
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Affiliation(s)
- Clemente J Britto
- Yale Adult Cystic Fibrosis Program, Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Internal Medicine, Yale University School of Medicine.
| | - Felix Ratjen
- Division of Respiratory Medicine, Translational Medicine, University of Toronto Hospital for Sick Children, 555 University Avenue, Toronto Ontario M5G 1X8, Canada
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Guimbellot JS, Nichols DP, Brewington JJ. Novel Applications of Biomarkers and Personalized Medicine in Cystic Fibrosis. Clin Chest Med 2022; 43:617-630. [PMID: 36344070 DOI: 10.1016/j.ccm.2022.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
As routine care in cystic fibrosis (CF) becomes increasingly personalized, new opportunities to further focus care on the individual have emerged. These opportunities are increasingly filled through research in tools aiding drug selection, drug monitoring and titration, disease-relevant biomarkers, and evaluation of therapeutic benefits. Herein, we will discuss such research tools presently being translated into the clinic to improve the personalization of care in CF.
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Affiliation(s)
- Jennifer S Guimbellot
- Department of Pediatrics, Division of Pulmonary and Sleep Medicine, Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham; 1600 7th Avenue South, ACC 620, Birmingham, AL 35233, USA
| | - David P Nichols
- Department of Pediatrics, Division of Pulmonary Medicine, Seattle Children's Hospital, University of Washington School of Medicine, Building Cure, 1920 Terry Avenue, Office 4-209, Seattle, WA 98109, USA
| | - John J Brewington
- Department of Pediatrics, University of Cincinnati College of Medicine, 3230 Eden Avenue, Cincinnati, OH 45267, USA; Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, MLC 2021, Cincinnati, OH 45229, USA.
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9
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Bowerman C, Ratjen F, Stanojevic S. Estimating the minimum sample size for interventional and observational studies using the lung clearance index as an endpoint✰. J Cyst Fibros 2022; 22:356-362. [PMID: 36402729 DOI: 10.1016/j.jcf.2022.11.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 10/16/2022] [Accepted: 11/10/2022] [Indexed: 11/18/2022]
Abstract
BACKGROUND With the increasing availability of highly effective modulators for people living with cystic fibrosis (CF), there is a need to re-design research studies to reflect the changing epidemiology of the CF population. The lung clearance index (LCI), a sensitive physiological measure of lung function, may be ideally suited as an endpoint in the era of CF modulator therapies. In this study we describe study design considerations for implementing LCI into interventional and observational research. METHODS Simulations were used to estimate the required sample size to detect a range of treatment effects for interventional studies (including cross-over trials) and to track lung disease progression in observational studies. RESULTS Using published treatment effects to inform the design of prospective studies can lead to inefficient study designs. Large improvements in LCI for a few individuals can skew results and can influence interpretations of treatment effects. Adjusting for baseline LCI can help to improve the efficiency of a study. Compared to the forced expiratory volume in 1 second (FEV1), analysis using LCI as an endpoint requires as little as one third of the total sample size. CONCLUSIONS Planning of prospective studies that include LCI as an endpoint need to consider baseline LCI and disease severity of the study population; whereas interpretation of results needs to consider whether a few individuals skew the overall treatment effect.
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10
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Terlizzi V, Parisi GF, Ferrari B, Castellani C, Manti S, Leonardi S, Taccetti G. Effect of Dornase Alfa on the Lung Clearance Index in Children with Cystic Fibrosis: A Lesson from a Case Series. CHILDREN (BASEL, SWITZERLAND) 2022; 9:1625. [PMID: 36360353 PMCID: PMC9688561 DOI: 10.3390/children9111625] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 10/15/2022] [Accepted: 10/24/2022] [Indexed: 09/12/2023]
Abstract
BACKGROUND Dornase alfa (DNase) is the only mucus-degrading agent that has proven efficacy in cystic fibrosis (CF). Few studies have evaluated the effects of DNase on the lung clearance index (LCI). We report the experience of two CF centers in which LCI monitoring was used to evaluate the efficacy of DNase therapy. METHODS This is a prospective and observational study, evaluating the effects of DNase therapy on LCI values in three CF children followed at CF centers in Florence and Catania, Italy. In both centers, LCI was performed routinely, every 3-6 months, based on the clinical picture and severity of the lung disease. In this study, we evaluated the LCI before and after long-term DNase therapy. RESULTS DNase improved LCI values in the absence of respiratory exacerbations: in case n. 1 LCI decreased by 39% in 16 months (from 11.1 to 6.8); in case n. 2 by 20% in 12 months (from 9.3 to 7.4); in case n. 3 by 24% in 16 months (from 9.3 to 7.0). CONCLUSIONS This case series confirms the efficacy of DNase therapy in CF children, as demonstrated by the LCI reduction in treated patients. Furthermore, our results suggest that LCI is a sensitive marker of disease and can be used for the evaluation of response to treatment.
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Affiliation(s)
- Vito Terlizzi
- Cystic Fibrosis Regional Reference Center, Department of Paediatric Medicine, Meyer Children’s Hospital, 50139 Florence, Italy
| | - Giuseppe Fabio Parisi
- Pediatric Respiratory and Cystic Fibrosis Unit, Department of Clinical and Experimental Medicine, San Marco Hospital, University of Catania, 95121 Catania, Italy
| | - Beatrice Ferrari
- Rehabilitation Unit, Meyer Children’s Hospital, 50139 Florence, Italy
| | - Chiara Castellani
- Rehabilitation Unit, Meyer Children’s Hospital, 50139 Florence, Italy
| | - Sara Manti
- Pediatric Respiratory and Cystic Fibrosis Unit, Department of Clinical and Experimental Medicine, San Marco Hospital, University of Catania, 95121 Catania, Italy
- Pediatric Unit, Department of Human and Pediatric Pathology “Gaetano Barresi”, AOUP G. Martino, University of Messina, Via Consolare Valeria, 1, 98124 Messina, Italy
| | - Salvatore Leonardi
- Pediatric Respiratory and Cystic Fibrosis Unit, Department of Clinical and Experimental Medicine, San Marco Hospital, University of Catania, 95121 Catania, Italy
| | - Giovanni Taccetti
- Cystic Fibrosis Regional Reference Center, Department of Paediatric Medicine, Meyer Children’s Hospital, 50139 Florence, Italy
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11
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Muttoo S, Jeena PM, Röösli M, de Hoogh K, Meliefste K, Tularam H, Olin AC, Carlsen HK, Mentz G, Asharam K, Naidoo RN. Effect of short-term exposure to ambient nitrogen dioxide and particulate matter on repeated lung function measures in infancy: A South African birth cohort. ENVIRONMENTAL RESEARCH 2022; 213:113645. [PMID: 35700764 DOI: 10.1016/j.envres.2022.113645] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 06/02/2022] [Accepted: 06/06/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND The developing lung is highly susceptible to environmental toxicants, with both short- and long-term exposure to ambient air pollutants linked to early childhood effects. This study assessed the short-term exposure effects of nitrogen dioxide (NO2) and particulate matter (PM10) on lung function in infants aged 6 weeks, 6, 12 and 24 months, the early developmental phase of child growth. METHODS Lung function was determined by multiple breath washout and tidal breathing measurement in non-sedated infants. Individual exposure to NO2 and PM10 was determined by hybrid land use regression and dispersion modelling, with two-week average estimates (preceding the test date). Linear mixed models were used to adjust for the repeated measures design and an age*exposure interaction was introduced to obtain effect estimates for each age group. RESULTS There were 165 infants that had lung function testing, with 82 of them having more than one test occasion. Exposure to PM10 (μg/m3) resulted in a decline in tidal volume at 6 weeks [-0.4 ml (-0.9; 0.0), p = 0.065], 6 months [-0.5 ml (-1.0; 0.0), p = 0.046] and 12 months [-0.3 ml (-0.7; 0.0), p = 0.045]. PM10 was related to an increase in respiratory rate and minute ventilation, while a decline was observed for functional residual capacity for the same age groups, though not statistically significant for these outcomes. Such associations were however less evident for exposure to NO2, with inconsistent changes observed across measurement parameters and age groups. CONCLUSION Our study suggests that PM10 results in acute lung function impairments among infants from a low-socioeconomic setting, while the association with NO2 is less convincing.
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Affiliation(s)
- S Muttoo
- Discipline of Occupational and Environmental Health, University of KwaZulu-Natal, Durban, South Africa.
| | - P M Jeena
- Discipline of Paediatrics and Child Health, University of KwaZulu-Natal, Durban, South Africa.
| | - M Röösli
- Swiss Tropical and Public Health Institute, Basel, Switzerland.
| | - K de Hoogh
- Swiss Tropical and Public Health Institute, Basel, Switzerland.
| | - K Meliefste
- Institute for Risk Assessment Sciences, Utrecht, the Netherlands.
| | - H Tularam
- Discipline of Occupational and Environmental Health, University of KwaZulu-Natal, Durban, South Africa.
| | - A C Olin
- Department of Occupational and Environmental Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden.
| | - H K Carlsen
- Department of Occupational and Environmental Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden.
| | - G Mentz
- University Michigan, Ann Arbor, MI, USA.
| | - K Asharam
- Discipline of Occupational and Environmental Health, University of KwaZulu-Natal, Durban, South Africa.
| | - R N Naidoo
- Discipline of Occupational and Environmental Health, University of KwaZulu-Natal, Durban, South Africa.
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12
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Macdougall A, Jarvis D, Keogh RH, Bowerman C, Bilton D, Davies G, Carr SB, Stanojevic S. Trajectories of early growth and subsequent lung function in cystic fibrosis: An observational study using UK and Canadian registry data. J Cyst Fibros 2022:S1569-1993(22)00658-0. [PMID: 36088206 DOI: 10.1016/j.jcf.2022.09.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 08/18/2022] [Accepted: 09/01/2022] [Indexed: 10/14/2022]
Abstract
BACKGROUND Understanding the pulmonary impact of changes in early life nutritional status over time in a paediatric CF population may help inform how to use nutritional assessment to guide clinical care. National registry data provides an opportunity to study patterns of weight gain over time at the level of the individual, and thus to gain detailed understanding of the relationship between early weight trajectories and later lung function in children with Cystic Fibrosis (CF). METHODS Using data from the United Kingdom (UK) and Canadian CF Registries, a mixed effects linear regression model was used to describe children's weight and BMI z-score trajectories from age 1 to 5 years. The intercept (weight-for-age at age 1) and slope (weight-for-age trajectory) from this model were then used as covariates in a linear regression of first lung function measurement at age 6 years. RESULTS In both the UK and Canadian data, greater weight-for-age z-score at age 1 year and greater change in weight-for-age over time were associated with higher FEV1% predicted. A greater weight-for-age z-score at age 1 year was associated with a higher FEV1% predicted (UK: 3.78% (95% CI: 1.76; 4.70); Canada: 3.20% (95%CI: 1.76, 4.70)). These associations were reproduced for BMI z-scores and FVC% predicted. CONCLUSIONS Early weight-for-age, specifically at age 1 year, and weight-for-age trajectories across early childhood are associated with later lung function. This relationship persists after adjustment for potential confounders. Current guidelines may need to be updated to place less emphasis on a specific cut-off (such as the 10th percentile) and encourage tracking of weight-for-age over time.
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Affiliation(s)
- Amy Macdougall
- National Heart and Lung Institute, Imperial College London, London, United Kingdom.
| | - Deborah Jarvis
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Ruth H Keogh
- Department of Medical Statistics, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Cole Bowerman
- Department of Community Health & Epidemiology, Dalhousie University, Halifax, Canada
| | - Diana Bilton
- Royal Brompton and Harefield NHS Foundation Trust, National Heart and Lung Institute, Imperial College, Sydney Street, London, United Kingdom
| | - Gwyneth Davies
- UCL Great Ormond Street Institute of Child Health, London, UK, Great Ormond Street Hospital for Children and GOSH NIHR BRC, London, United Kingdom
| | - Siobhán B Carr
- Royal Brompton Hospital and Imperial College London, United Kingdom
| | - Sanja Stanojevic
- Department of Community Health & Epidemiology, Dalhousie University, Halifax, Canada
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13
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Whitfield CA, Horsley A, Jensen OE, Horn FC, Collier GJ, Smith LJ, Wild JM. Model-based Bayesian inference of the ventilation distribution in patients with cystic fibrosis from multiple breath washout, with comparison to ventilation MRI. Respir Physiol Neurobiol 2022; 302:103919. [PMID: 35562095 DOI: 10.1016/j.resp.2022.103919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 04/06/2022] [Accepted: 05/05/2022] [Indexed: 10/18/2022]
Abstract
BACKGROUND Indices of ventilation heterogeneity (VH) from multiple breath washout (MBW) have been shown to correlate well with VH indices derived from hyperpolarised gas ventilation MRI. Here we report the prediction of ventilation distributions from MBW data using a mathematical model, and the comparison of these predictions with imaging data. METHODS We developed computer simulations of the ventilation distribution in the lungs to model MBW measurement with 3 parameters: σV, determining the extent of VH; V0, the lung volume; and VD, the dead-space volume. These were inferred for each individual from supine MBW data recorded from 25 patients with cystic fibrosis (CF) using approximate Bayesian computation. The fitted models were used to predict the distribution of gas imaged by 3He ventilation MRI measurements collected from the same visit. RESULTS The MRI indices measured (I1/3, the fraction of pixels below one-third of the mean intensity and ICV, the coefficient of variation of pixel intensity) correlated strongly with those predicted by the MBW model fits (r=0.93,0.88 respectively). There was also good agreement between predicted and measured MRI indices (mean bias ± limits of agreement: I1/3:-0.003±0.118 and ICV:-0.004±0.298). Fitted model parameters were robust to truncation of MBW data. CONCLUSION We have shown that the ventilation distribution in the lung can be inferred from an MBW signal, and verified this using ventilation MRI. The Bayesian method employed extracts this information with fewer breath cycles than required for LCI, reducing acquisition time required, and gives uncertainty bounds, which are important for clinical decision making.
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Affiliation(s)
- Carl A Whitfield
- Division of Infection, Immunity and Respiratory Medicine, University of Manchester, Manchester, UK; Department of Mathematics, University of Manchester, Manchester, UK.
| | - Alexander Horsley
- Division of Infection, Immunity and Respiratory Medicine, University of Manchester, Manchester, UK
| | - Oliver E Jensen
- Department of Mathematics, University of Manchester, Manchester, UK
| | - Felix C Horn
- POLARIS, Imaging Sciences, Department of Infection, Immunity & Cardiovascular Disease, University of Sheffield, UK
| | - Guilhem J Collier
- POLARIS, Imaging Sciences, Department of Infection, Immunity & Cardiovascular Disease, University of Sheffield, UK
| | - Laurie J Smith
- POLARIS, Imaging Sciences, Department of Infection, Immunity & Cardiovascular Disease, University of Sheffield, UK
| | - Jim M Wild
- POLARIS, Imaging Sciences, Department of Infection, Immunity & Cardiovascular Disease, University of Sheffield, UK
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14
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Kooner HK, McIntosh MJ, Matheson AM, Venegas C, Radadia N, Ho T, Haider EA, Konyer NB, Santyr GE, Albert MS, Ouriadov A, Abdelrazek M, Kirby M, Dhaliwal I, Nicholson JM, Nair P, Svenningsen S, Parraga G. 129Xe MRI ventilation defects in ever-hospitalised and never-hospitalised people with post-acute COVID-19 syndrome. BMJ Open Respir Res 2022; 9:9/1/e001235. [PMID: 35584850 PMCID: PMC9119175 DOI: 10.1136/bmjresp-2022-001235] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 05/05/2022] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND Patients often report persistent symptoms beyond the acute infectious phase of COVID-19. Hyperpolarised 129Xe MRI provides a way to directly measure airway functional abnormalities; the clinical relevance of 129Xe MRI ventilation defects in ever-hospitalised and never-hospitalised patients who had COVID-19 has not been ascertained. It remains unclear if persistent symptoms beyond the infectious phase are related to small airways disease and ventilation heterogeneity. Hence, we measured 129Xe MRI ventilation defects, pulmonary function and symptoms in ever-hospitalised and never-hospitalised patients who had COVID-19 with persistent symptoms consistent with post-acute COVID-19 syndrome (PACS). METHODS Consenting participants with a confirmed diagnosis of PACS completed 129Xe MRI, CT, spirometry, multi-breath inert-gas washout, 6-minute walk test, St. George's Respiratory Questionnaire (SGRQ), modified Medical Research Council (mMRC) dyspnoea scale, modified Borg scale and International Physical Activity Questionnaire. Consenting ever-COVID volunteers completed 129Xe MRI and pulmonary function tests only. RESULTS Seventy-six post-COVID and nine never-COVID participants were evaluated. Ventilation defect per cent (VDP) was abnormal and significantly greater in ever-COVID as compared with never-COVID participants (p<0.001) and significantly greater in ever-hospitalised compared with never-hospitalised participants who had COVID-19 (p=0.048), in whom diffusing capacity of the lung for carbon-monoxide (p=0.009) and 6-minute walk distance (6MWD) (p=0.005) were also significantly different. 129Xe MRI VDP was also related to the 6MWD (p=0.02) and post-exertional SpO2 (p=0.002). Participants with abnormal VDP (≥4.3%) had significantly worse 6MWD (p=0.003) and post-exertional SpO2 (p=0.03). CONCLUSION 129Xe MRI VDP was significantly worse in ever-hospitalised as compared with never-hospitalised participants and was related to 6MWD and exertional SpO2 but not SGRQ or mMRC scores. TRIAL REGISTRATION NUMBER NCT05014516.
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Affiliation(s)
- Harkiran K Kooner
- Robarts Research Institute, Western University, London, Ontario, Canada.,Department of Medical Biophysics, Western University, London, Ontario, Canada
| | - Marrissa J McIntosh
- Robarts Research Institute, Western University, London, Ontario, Canada.,Department of Medical Biophysics, Western University, London, Ontario, Canada
| | - Alexander M Matheson
- Robarts Research Institute, Western University, London, Ontario, Canada.,Department of Medical Biophysics, Western University, London, Ontario, Canada
| | - Carmen Venegas
- Firestone Institute for Respiratory Health, St. Joseph's Healthcare, Hamilton, Ontario, Canada.,Division of Respirology, Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Nisarg Radadia
- Division of Respirology, Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Terence Ho
- Firestone Institute for Respiratory Health, St. Joseph's Healthcare, Hamilton, Ontario, Canada.,Division of Respirology, Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | | | - Norman B Konyer
- Imaging Research Centre, St. Joseph's Healthcare, Hamilton, Ontario, Canada
| | - Giles E Santyr
- The Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Mitchell S Albert
- Department of Chemistry, Lakehead University, Thunder Bay, Ontario, Canada.,Thunder Bay Regional Health Research Institute, Thunder Bay, Ontario, Canada
| | - Alexei Ouriadov
- Department of Physics and Astronomy, Western University, London, Ontario, Canada
| | - Mohamed Abdelrazek
- Department of Medical Imaging, Western University, London, Ontario, Canada
| | - Miranda Kirby
- Department of Physics, Ryerson University, Toronto, Ontario, Canada
| | - Inderdeep Dhaliwal
- Division of Respirology, Department of Medicine, Western University, London, Ontario, Canada
| | - J Michael Nicholson
- Division of Respirology, Department of Medicine, Western University, London, Ontario, Canada
| | - Parameswaran Nair
- Firestone Institute for Respiratory Health, St. Joseph's Healthcare, Hamilton, Ontario, Canada.,Division of Respirology, Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Sarah Svenningsen
- Firestone Institute for Respiratory Health, St. Joseph's Healthcare, Hamilton, Ontario, Canada.,Division of Respirology, Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Grace Parraga
- Robarts Research Institute, Western University, London, Ontario, Canada .,Department of Medical Biophysics, Western University, London, Ontario, Canada.,Division of Respirology, Department of Medicine, Western University, London, Ontario, Canada
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15
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Irving S, Bayfield K, Davies JC, Bush A. Curvilinearity provides additional information to lung clearance index only in a minority of children with early cystic fibrosis lung disease. ERJ Open Res 2022; 8:00582-2021. [PMID: 35386828 PMCID: PMC8977591 DOI: 10.1183/23120541.00582-2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 02/17/2022] [Indexed: 11/21/2022] Open
Abstract
Advances in technology and international consensus guidelines [1] make multiple breath washout (MBW) testing feasible in many settings, particularly in cystic fibrosis (CF) centres, and in paediatrics, as many children and young people with respiratory disease may have normal spirometry [2]. Curvilinearity, as calculated from multiple-breath washout, is abnormal in a small number of children with cystic fibrosis when other tests are still normalhttps://bit.ly/3p9QAV4
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16
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Stanojevic S, Bowerman C, Robinson P. Multiple breath washout: measuring early manifestations of lung pathology. Breathe (Sheff) 2022; 17:210016. [PMID: 35035543 PMCID: PMC8753656 DOI: 10.1183/20734735.0016-2021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 07/13/2021] [Indexed: 11/05/2022] Open
Abstract
The multiple breath washout (MBW) test measures the efficiency of gas mixing in the lungs and has gained significant interest over the past 20 years. MBW outcomes detect early lung function impairment and peripheral airway pathology, through its main outcome measure lung clearance index (LCI). LCI measures the number of lung turnovers required to washout an inert tracer gas. MBW is performed during normal (tidal) breathing, making it particularly suitable for young children or those who have trouble performing forced manoeuvres. Additionally, research in chronic respiratory disease populations has shown that MBW can detect acute clinically relevant changes before conventional lung function tests, such as spirometry, thus enabling early intervention. The development of technical standards for MBW and commercial devices have allowed MBW to be implemented in clinical research and potentially routine clinical practice. Although studies have summarised clinimetric properties of MBW indices, additional research is required to establish the clinical utility of MBW and, if possible, shorten testing time. Sensitive, feasible measures of early lung function decline will play an important role in early intervention for people living with respiratory diseases. Educational aim To describe the multiple breath washout test, its applications to lung pathology and respiratory disease, as well as directions for future research.
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Affiliation(s)
- Sanja Stanojevic
- Dept of Community Health and Epidemiology, Dalhousie University, Halifax, NS, Canada
| | - Cole Bowerman
- Dept of Community Health and Epidemiology, Dalhousie University, Halifax, NS, Canada
| | - Paul Robinson
- Dept of Respiratory Medicine, Children's Hospital at Westmead, Sydney, Australia.,The Children's Hospital at Westmead Clinical School, The University of Sydney, Sydney, Australia
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17
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Landini N, Ciet P, Janssens HM, Bertolo S, Ros M, Mattone M, Catalano C, Majo F, Costa S, Gramegna A, Lucca F, Parisi GF, Saba L, Tiddens HAWM, Morana G. Management of respiratory tract exacerbations in people with cystic fibrosis: Focus on imaging. Front Pediatr 2022; 10:1084313. [PMID: 36814432 PMCID: PMC9940849 DOI: 10.3389/fped.2022.1084313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Accepted: 12/28/2022] [Indexed: 02/09/2023] Open
Abstract
Respiratory tract exacerbations play a crucial role in progressive lung damage of people with cystic fibrosis, representing a major determinant in the loss of functional lung tissue, quality of life and patient survival. Detection and monitoring of respiratory tract exacerbations are challenging for clinicians, since under- and over-treatment convey several risks for the patient. Although various diagnostic and monitoring tools are available, their implementation is hampered by the current definition of respiratory tract exacerbation, which lacks objective "cut-offs" for clinical and lung function parameters. In particular, the latter shows a large variability, making the current 10% change in spirometry outcomes an unreliable threshold to detect exacerbation. Moreover, spirometry cannot be reliably performed in preschool children and new emerging tools, such as the forced oscillation technique, are still complementary and need more validation. Therefore, lung imaging is a key in providing respiratory tract exacerbation-related structural and functional information. However, imaging encompasses several diagnostic options, each with different advantages and limitations; for instance, conventional chest radiography, the most used radiological technique, may lack sensitivity and specificity in respiratory tract exacerbations diagnosis. Other methods, including computed tomography, positron emission tomography and magnetic resonance imaging, are limited by either radiation safety issues or the need for anesthesia in uncooperative patients. Finally, lung ultrasound has been proposed as a safe bedside option but it is highly operator-dependent and there is no strong evidence of its possible use during respiratory tract exacerbation. This review summarizes the clinical challenges of respiratory tract exacerbations in patients with cystic fibrosis with a special focus on imaging. Firstly, the definition of respiratory tract exacerbation is examined, while diagnostic and monitoring tools are briefly described to set the scene. This is followed by advantages and disadvantages of each imaging technique, concluding with a diagnostic imaging algorithm for disease monitoring during respiratory tract exacerbation in the cystic fibrosis patient.
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Affiliation(s)
- Nicholas Landini
- Department of Radiological, Oncological and Pathological Sciences, Policlinico Umberto I Hospital, "Sapienza" Rome University, Rome, Italy
| | - Pierluigi Ciet
- Department of Radiology and Nuclear Medicine, Erasmus MC - Sophia, Rotterdam, Netherlands.,Department of Radiology, University Cagliari, Cagliari, Italy.,Department of Pediatrics, division of Respiratory Medicine and Allergology, Erasmus MC - Sophia Children's Hospital, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Hettie M Janssens
- Department of Pediatrics, division of Respiratory Medicine and Allergology, Erasmus MC - Sophia Children's Hospital, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Silvia Bertolo
- Department of Radiology, S. Maria Ca'Foncello Regional Hospital, Treviso, Italy
| | - Mirco Ros
- Department of Pediatrics, Ca'Foncello S. Maria Hospital, Treviso, Italy
| | - Monica Mattone
- Department of Radiological, Oncological and Pathological Sciences, Policlinico Umberto I Hospital, "Sapienza" Rome University, Rome, Italy
| | - Carlo Catalano
- Department of Radiological, Oncological and Pathological Sciences, Policlinico Umberto I Hospital, "Sapienza" Rome University, Rome, Italy
| | - Fabio Majo
- Pediatric Pulmonology & Cystic Fibrosis Unit Bambino Gesú Children's Hospital, IRCCS Rome, Rome, Italy
| | - Stefano Costa
- Department of Pediatrics, Gaetano Martino Hospital, Messina, Italy
| | - Andrea Gramegna
- Department of Pathophisiology and Transplantation, University of Milan, Milan, Italy.,Respiratory Disease and Adult Cystic Fibrosis Centre, Internal Medicine Department, IRCCS Ca' Granda, Milan, Italy
| | - Francesca Lucca
- Regional Reference Cystic Fibrosis Center, University Hospital of Verona, Verona, Italy
| | - Giuseppe Fabio Parisi
- Pediatric Pulmonology Unit, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Luca Saba
- Department of Radiology, University Cagliari, Cagliari, Italy
| | - Harm A W M Tiddens
- Department of Radiology and Nuclear Medicine, Erasmus MC - Sophia, Rotterdam, Netherlands.,Department of Pediatrics, division of Respiratory Medicine and Allergology, Erasmus MC - Sophia Children's Hospital, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Giovanni Morana
- Department of Radiology, S. Maria Ca'Foncello Regional Hospital, Treviso, Italy
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18
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Lung Clearance Index in Children with Cystic Fibrosis during Pulmonary Exacerbation. J Clin Med 2021; 10:jcm10214884. [PMID: 34768401 PMCID: PMC8584600 DOI: 10.3390/jcm10214884] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 10/13/2021] [Accepted: 10/19/2021] [Indexed: 11/16/2022] Open
Abstract
(1) Background: Pulmonary exacerbation (PEx) is one of the main factors affecting the quality of life and life expectancy in patients with cystic fibrosis (CF). Our study aimed to evaluate the change in selected pulmonary function parameters, including lung clearance index (LCI), in patients with CF diagnosed with PEx. (2) Methods: We enrolled 40 children with CF aged 6–17. They performed spirometry and multiple breath nitrogen washout (MBNW) tests during a stable condition period at the beginning and the end of intravenous antibiotic treatment. (3) Results: LCI increased by 65% and FEV1 decreased by ≥10% in 40% of patients with CF during PEx. An absolute change in LCI between a stable condition period and PEx was 1.05 (±1.92) units, which corresponds to a relative change of 11.48% (±18.61) of the baseline. The relative decrease in FEV1 was −9.22% (±12.00) and the z-score was −0.67 (±1.13). After the PEx treatment, FEV1 increased by 11.05% (±9.04) on average, whereas LCI decreased by 1.21 ± 1.59 units on average, which represented 9.42% ± 11.40 compared to the value at the beginning of PEx. (4) Conclusions: The change in LCI captures a higher proportion of events with functional impairment than FEV1 in school-age children with CF.
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19
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The effect of acute maximal exercise on the regional distribution of ventilation using ventilation MRI in CF. J Cyst Fibros 2021; 20:625-631. [DOI: 10.1016/j.jcf.2020.08.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 08/11/2020] [Accepted: 08/11/2020] [Indexed: 01/02/2023]
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20
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Bergeron C, Cantin AM. New Therapies to Correct the Cystic Fibrosis Basic Defect. Int J Mol Sci 2021; 22:ijms22126193. [PMID: 34201249 PMCID: PMC8227161 DOI: 10.3390/ijms22126193] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 05/31/2021] [Accepted: 06/04/2021] [Indexed: 12/24/2022] Open
Abstract
Rare diseases affect 400 million individuals worldwide and cause significant morbidity and mortality. Finding solutions for rare diseases can be very challenging for physicians and researchers. Cystic fibrosis (CF), a genetic, autosomal recessive, multisystemic, life-limiting disease does not escape this sad reality. Despite phenomenal progress in our understanding of this disease, treatment remains difficult. Until recently, therapies for CF individuals were focused on symptom management. The discovery of the cystic fibrosis transmembrane conductance regulator (CFTR) gene and its product, a protein present at the apical surface of epithelial cells regulating ion transport, allowed the scientific community to learn about the basic defect in CF and to study potential therapies targeting the dysfunctional protein. In the past few years, promising therapies with the goal to restore CFTR function became available and changed the lives of several CF patients. These medications, called CFTR modulators, aim to correct, potentialize, stabilize or amplify CFTR function. Furthermore, research is ongoing to develop other targeted therapies that could be more efficient and benefit a larger proportion of the CF community. The purpose of this review is to summarize our current knowledge of CF genetics and therapies restoring CFTR function, particularly CFTR modulators and gene therapy.
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Affiliation(s)
- Christelle Bergeron
- Department of Medicine, Respiratory Division, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, QC J1H 5N4, Canada;
| | - André M. Cantin
- Department of Medicine, Respiratory Division, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, QC J1H 5N4, Canada;
- Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Respiratory Division, Faculty of Medicine, University of Sherbrooke, 3001, 12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
- Correspondence: ; Tel.: +1-819-346-1110 (ext. 14893); Fax: +1-819-564-5377
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21
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Dincel A, Yilmaz Yegit C, Ergenekon AP, Erdem Eralp E, Gokdemir Y, Kiyan G, Karadag B. Long-term respiratory outcomes of post-op congenital lung malformations. Pediatr Int 2021; 63:704-709. [PMID: 32991002 DOI: 10.1111/ped.14488] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/17/2020] [Accepted: 09/18/2020] [Indexed: 01/22/2023]
Abstract
BACKGROUND Congenital lung malformations (CLM) are rare disorders and surgical intervention is the definitive treatment. Our aim is to evaluate the long-term lung function of patients with CLM after surgery compared to healthy children. METHODS Sixteen children with CLM (M/F: 9/7) and 30 age-matched, healthy controls (M/F: 13/17) were included in the study. Demographic data were recorded and both groups were compared by spirometry and the nitrogen-based Lung Clearance Index (LCI). RESULTS Mean ± SD age of the patients was 12.0 ± 5.4 years. The mean forced expiratory volume in 1 s (FEV1 ), forced vital capacity (FVC), FEV1 /FVC, and forced expiratory flow between 25% and 75% of force expiration (FEF25-75 ) predicted was, 86.68 ± 16.65, 88.00 ± 14.58, 97.44 ± 9.89, and 79.00 ± 26.41, respectively in the patient group. Patients with CLM had significantly lower values in FEV1 , FVC, FEF25-75 than healthy controls (P = 0.002, P 0.007, P 0.045). While the mean LCI2,5% value in patients' group was 8.33 ± 1.52, it was 7.28 ± 0.80 in healthy controls (P = 0.023). Strong inverse correlation between LCI and FEV1 , FEV1 /FVC was detected in the patient group (P = 0.023; r: -0.581, P 0.017; r: -0.606 respectively). CONCLUSION This study revealed that, in long-term follow-up, patients who had surgery because of CLM have impairment in the pulmonary function compared to healthy children and LCI may be more accurate in detecting airway diseases early than spirometry.
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Affiliation(s)
- Alican Dincel
- Department of Pediatrics, School of Medicine, Marmara University, Istanbul, Turkey
| | - Cansu Yilmaz Yegit
- Division of Pediatric Pulmonology, School of Medicine, Marmara University, Istanbul, Turkey
| | - Almala Pinar Ergenekon
- Division of Pediatric Pulmonology, School of Medicine, Marmara University, Istanbul, Turkey
| | - Ela Erdem Eralp
- Division of Pediatric Pulmonology, School of Medicine, Marmara University, Istanbul, Turkey
| | - Yasemin Gokdemir
- Division of Pediatric Pulmonology, School of Medicine, Marmara University, Istanbul, Turkey
| | - Gursu Kiyan
- Department of Pediatric Surgery, School of Medicine, Marmara University, Istanbul, Turkey
| | - Bulent Karadag
- Division of Pediatric Pulmonology, School of Medicine, Marmara University, Istanbul, Turkey
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22
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Brooke JP, Hall IP. Novel Thoracic MRI Approaches for the Assessment of Pulmonary Physiology and Inflammation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1304:123-145. [PMID: 34019267 DOI: 10.1007/978-3-030-68748-9_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Excessive pulmonary inflammation can lead to damage of lung tissue, airway remodelling and established structural lung disease. Novel therapeutics that specifically target inflammatory pathways are becoming increasingly common in clinical practice, but there is yet to be a similar stepwise change in pulmonary diagnostic tools. A variety of thoracic magnetic resonance imaging (MRI) tools are currently in development, which may soon fulfil this emerging clinical need for highly sensitive assessments of lung structure and function. Given conventional MRI techniques are poorly suited to lung imaging, alternate strategies have been developed, including the use of inhaled contrast agents, intravenous contrast and specialized lung MR sequences. In this chapter, we discuss technical challenges of performing MRI of the lungs and how they may be overcome. Key thoracic MRI modalities are reviewed, namely, hyperpolarized noble gas MRI, oxygen-enhanced MRI (OE-MRI), ultrashort echo time (UTE) MRI and dynamic contrast-enhanced (DCE) MRI. Finally, we consider potential clinical applications of these techniques including phenotyping of lung disease, evaluation of novel pulmonary therapeutic efficacy and longitudinal assessment of specific patient groups.
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Affiliation(s)
- Jonathan P Brooke
- Department of Respiratory Medicine, University of Nottingham, Queens Medical Centre, Nottingham, UK.
| | - Ian P Hall
- Department of Respiratory Medicine, University of Nottingham, Queens Medical Centre, Nottingham, UK.
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23
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Bayfield KJ, Douglas TA, Rosenow T, Davies JC, Elborn SJ, Mall M, Paproki A, Ratjen F, Sly PD, Smyth AR, Stick S, Wainwright CE, Robinson PD. Time to get serious about the detection and monitoring of early lung disease in cystic fibrosis. Thorax 2021; 76:1255-1265. [PMID: 33927017 DOI: 10.1136/thoraxjnl-2020-216085] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 02/24/2021] [Accepted: 03/10/2021] [Indexed: 12/26/2022]
Abstract
Structural and functional defects within the lungs of children with cystic fibrosis (CF) are detectable soon after birth and progress throughout preschool years often without overt clinical signs or symptoms. By school age, most children have structural changes such as bronchiectasis or gas trapping/hypoperfusion and lung function abnormalities that persist into later life. Despite improved survival, gains in forced expiratory volume in one second (FEV1) achieved across successive birth cohorts during childhood have plateaued, and rates of FEV1 decline in adolescence and adulthood have not slowed. This suggests that interventions aimed at preventing lung disease should be targeted to mild disease and commence in early life. Spirometry-based classifications of 'normal' (FEV1≥90% predicted) and 'mild lung disease' (FEV1 70%-89% predicted) are inappropriate, given the failure of spirometry to detect significant structural or functional abnormalities shown by more sensitive imaging and lung function techniques. The state and readiness of two imaging (CT and MRI) and two functional (multiple breath washout and oscillometry) tools for the detection and monitoring of early lung disease in children and adults with CF are discussed in this article.Prospective research programmes and technological advances in these techniques mean that well-designed interventional trials in early lung disease, particularly in young children and infants, are possible. Age appropriate, randomised controlled trials are critical to determine the safety, efficacy and best use of new therapies in young children. Regulatory bodies continue to approve medications in young children based on safety data alone and extrapolation of efficacy results from older age groups. Harnessing the complementary information from structural and functional tools, with measures of inflammation and infection, will significantly advance our understanding of early CF lung disease pathophysiology and responses to therapy. Defining clinical utility for these novel techniques will require effective collaboration across multiple disciplines to address important remaining research questions. Future impact on existing management burden for patients with CF and their family must be considered, assessed and minimised.To address the possible role of these techniques in early lung disease, a meeting of international leaders and experts in the field was convened in August 2019 at the Australiasian Cystic Fibrosis Conference. The meeting entitiled 'Shaping imaging and functional testing for early disease detection of lung disease in Cystic Fibrosis', was attended by representatives across the range of disciplines involved in modern CF care. This document summarises the proceedings, key priorities and important research questions highlighted.
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Affiliation(s)
- Katie J Bayfield
- Department of Respiratory Medicine, Children's Hospital at Westmead, Westmead, New South Wales, Australia
| | - Tonia A Douglas
- Department of Respiratory and Sleep Medicine, Queensland Children's Hospital, South Brisbane, Queensland, Australia.,Child Health Research Centre, The University of Queensland, Brisbane, Queensland, Australia
| | - Tim Rosenow
- Telethon Kids Institute, The University of Western Australia, Perth, Western Australia, Australia.,Centre for Child Health Research, The University of Western Australia, Perth, Western Australia, Australia.,Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, Perth, Western Australia, Australia
| | - Jane C Davies
- National Heart and Lung Institute, Imperial College London, London, UK.,Department of Paediatric Respiratory Medicine, Royal Brompton and Harefield NHS Foundation Trust, London, UK
| | - Stuart J Elborn
- Centre for Infection and Immunity, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
| | - Marcus Mall
- Department of Pediatric Pulmonology, Immunology, and Critical Care Medicine, Charité Universitätsmedizin Berlin, Berlin, Germany.,Berlin Institute of Health, Berlin, Germany.,Department of Translational Pulmonology, German Center for Lung Research, Berlin, Germany
| | - Anthony Paproki
- The Australian e-Health Research Centre, CSIRO, Brisbane, Queensland, Australia
| | - Felix Ratjen
- Translational Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada.,University of Toronto, Toronto, Ontario, Canada
| | - Peter D Sly
- Children's Health and Environment Program, Child Health Research Centre, The University of Queenland, Herston, Queensland, Australia
| | - Alan R Smyth
- Division of Child Health, Obstetrics & Gynaecology. School of Medicine, University of Nottingham, Nottingham, Nottinghamshire, UK
| | - Stephen Stick
- Telethon Kids Institute, The University of Western Australia, Perth, Western Australia, Australia.,Centre for Child Health Research, The University of Western Australia, Perth, Western Australia, Australia.,Department of Respiratory Medicine, Princess Margaret Hospital for Children, Perth, Western Australia, Australia
| | - Claire E Wainwright
- Department of Respiratory and Sleep Medicine, Queensland Children's Hospital, South Brisbane, Queensland, Australia.,Child Health Research Centre, The University of Queensland, Brisbane, Queensland, Australia
| | - Paul D Robinson
- Department of Respiratory Medicine, Children's Hospital at Westmead, Westmead, New South Wales, Australia .,Airway Physiology and Imaging Group, Woolcock Institute of Medical Research, Glebe, New South Wales, Australia.,The Discipline of Paediatrics and Child Health, The University of Sydney, Sydney, New South Wales, Australia
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24
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Yip KP, Stockley RA, Sapey E. Catching "Early" COPD - The Diagnostic Conundrum. Int J Chron Obstruct Pulmon Dis 2021; 16:957-968. [PMID: 33880020 PMCID: PMC8053524 DOI: 10.2147/copd.s296842] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Accepted: 03/21/2021] [Indexed: 01/21/2023] Open
Abstract
Chronic obstructive pulmonary disease (COPD) remains a leading cause of morbidity and mortality worldwide. Despite this, there has been little progress so far in terms of disease-modifying therapies over the last few decades and this is in part due to poor understanding of the definition and mechanisms surrounding early disease before it becomes established and increasingly complex. In this review, the nuances and difficulty in defining early disease in COPD are discussed. There are clear benefits in identifying patients early; however, usually diagnosis is made in the presence of significant lung damage. We consider what can be learned of early disease from COPD studies and highlight the lack of inclusion of young smokers (who may be at risk of COPD) or those with mild disease. We discuss promising clinical measures that are being used in an effort to detect early disease. These include symptom assessment, lung physiology measures and computed tomography (CT) imaging modalities. There is emerging evidence for the role of neutrophils and their proteinases in early COPD. This may form an important biomarker to investigate the pathophysiological processes of early COPD. Given the importance of the early disease, it is recommended that future COPD studies focus on capturing the earliest manifestations of disease, to understand the initiating mechanisms and to identify novel treatment targets.
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Affiliation(s)
- Kay Por Yip
- Birmingham Acute Care Research Group, Institute of Inflammation and Ageing, University of Birmingham, Edgbaston, Birmingham, UK
| | - Robert A Stockley
- Department of Respiratory Medicine, University Hospitals Birmingham NHS Foundation Trust, Edgbaston, Birmingham, UK
| | - Elizabeth Sapey
- Birmingham Acute Care Research Group, Institute of Inflammation and Ageing, University of Birmingham, Edgbaston, Birmingham, UK
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25
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Mondéjar-López P, Horsley A, Ratjen F, Bertolo S, de Vicente H, Asensio de la Cruz Ò. A multimodal approach to detect and monitor early lung disease in cystic fibrosis. Expert Rev Respir Med 2021; 15:761-772. [PMID: 33843417 DOI: 10.1080/17476348.2021.1908131] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Introduction: In the early stages, lung involvement in cystic fibrosis (CF) can be silent, with disease progression occurring in the absence of clinical symptoms. Irreversible airway damage is present in the early stages of disease; however, reliable biomarkers of early damage due to inflammation and infection that are universally applicable in day-to-day patient management have yet to be identified.Areas covered: At present, the main methods of detecting and monitoring early lung disease in CF are the lung clearance index (LCI), computed tomography (CT), and magnetic resonance imaging (MRI). LCI can be used to detect patients who may require more intense monitoring, identify exacerbations, and monitor responses to new interventions. High-resolution CT detects structural alterations in the lungs of CF patients with the best resolution of current imaging techniques. MRI is a radiation-free imaging alternative that provides both morphological and functional information. The role of MRI for short-term follow-up and pulmonary exacerbations is currently being investigated.Expert opinion: The roles of LCI and MRI are expected to expand considerably over the next few years. Meanwhile, closer collaboration between pulmonology and radiology specialties is an important goal toward improving care and optimizing outcomes in young patients with CF.
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Affiliation(s)
- Pedro Mondéjar-López
- Pediatric Pulmonologist, Pediatric Pulmonology and Cystic Fibrosis Unit, University Hospital Virgen de la Arrixaca, Murcia, Spain
| | - Alexander Horsley
- Honorary Consultant, Respiratory Research Group, Division of Infection, Immunity & Respiratory Medicine, University of Manchester, Manchester, UK
| | - Felix Ratjen
- Head, Division of Respiratory Medicine, Department of Pediatrics, Translational Medicine, Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
| | - Silvia Bertolo
- Radiologist, Department of Radiology, Ca'Foncello Regional Hospital, Treviso, Italy
| | | | - Òscar Asensio de la Cruz
- Pediatric Pulmonologist, Pediatric Unit, University Hospital Parc Taulí de Sabadell, Sabadell, Spain
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26
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Chukowry PS, Spittle DA, Turner AM. Small Airways Disease, Biomarkers and COPD: Where are We? Int J Chron Obstruct Pulmon Dis 2021; 16:351-365. [PMID: 33628018 PMCID: PMC7899307 DOI: 10.2147/copd.s280157] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 12/11/2020] [Indexed: 11/23/2022] Open
Abstract
The response to treatment and progression of Chronic Obstructive Pulmonary Disease (COPD) varies significantly. Small airways disease (SAD) is being increasingly recognized as a key pathological feature of COPD. Studies have brought forward pathological evidence of small airway damage preceding the development of emphysema and the detection of obstruction using traditional spirometry. In recent years, there has been a renewed interest in the early detection of SAD and this has brought along an increased demand for physiological tests able to identify and quantify SAD. Early detection of SAD allows early targeted therapy and this suggests the potential for altering the course of disease. The aim of this article is to review the evidence available on the physiological testing of small airways. The first half will focus on the role of lung function tests such as maximum mid-expiratory flow, impulse oscillometry and lung clearance index in detecting and quantifying SAD. The role of Computed Tomography (CT) as a radiological biomarker will be discussed as well as the potential of recent CT analysis software to differentiate normal aging of the lungs to pathology. The evidence behind SAD biomarkers sourced from blood as well as biomarkers sourced from sputum and broncho-alveolar lavage (BAL) will be reviewed. This paper focuses on CC-16, sRAGE, PAI-1, MMP-9 and MMP-12.
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Affiliation(s)
- Priyamvada S Chukowry
- Respiratory Research Department, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Daniella A Spittle
- Institute of Inflammation and Ageing, University of Birmingham, Birmingham, B15 2TT, UK
| | - Alice M Turner
- Institute for Applied Health Research, University of Birmingham, Birmingham, B15 2TT, UK
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27
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Hatziagorou E, Kampouras A, Avramidou V, Toulia I, Chrysochoou EA, Galogavrou M, Kirvassilis F, Tsanakas J. Toward the Establishment of New Clinical Endpoints for Cystic Fibrosis: The Role of Lung Clearance Index and Cardiopulmonary Exercise Testing. Front Pediatr 2021; 9:635719. [PMID: 33718306 PMCID: PMC7946844 DOI: 10.3389/fped.2021.635719] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 02/03/2021] [Indexed: 01/25/2023] Open
Abstract
As Cystic Fibrosis (CF) treatment advances, research evidence has highlighted the value and applicability of Lung Clearance Index and Cardiopulmonary Exercise Testing as endpoints for clinical trials. In the context of these new endpoints for CF trials, we have explored the use of these two test outcomes for routine CF care. In this review we have presented the use of these methods in assessing disease severity, disease progression, and the efficacy of new interventions with considerations for future research.
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Affiliation(s)
- Elpis Hatziagorou
- Pediatric Pulmonology and Cystic Fibrosis Unit, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Asterios Kampouras
- Pediatric Pulmonology and Cystic Fibrosis Unit, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Vasiliki Avramidou
- Pediatric Pulmonology and Cystic Fibrosis Unit, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Ilektra Toulia
- Pediatric Pulmonology and Cystic Fibrosis Unit, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Elisavet-Anna Chrysochoou
- Pediatric Pulmonology and Cystic Fibrosis Unit, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Maria Galogavrou
- Pediatric Pulmonology and Cystic Fibrosis Unit, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Fotios Kirvassilis
- Pediatric Pulmonology and Cystic Fibrosis Unit, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - John Tsanakas
- Pediatric Pulmonology and Cystic Fibrosis Unit, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
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28
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Short C, Saunders C, Davies J. Utility of lung clearance index in CF: What we know, what we don't know and musings on how to bridge the gap. J Cyst Fibros 2020; 19:852-855. [DOI: 10.1016/j.jcf.2020.10.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 10/21/2020] [Accepted: 10/22/2020] [Indexed: 11/26/2022]
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30
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Smith LJ, Horsley A, Bray J, Hughes PJC, Biancardi A, Norquay G, Wildman M, West N, Marshall H, Wild JM. The assessment of short and long term changes in lung function in CF using 129Xe MRI. Eur Respir J 2020; 56:2000441. [PMID: 32631840 DOI: 10.1183/13993003.00441-2020] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 06/29/2020] [Indexed: 12/22/2022]
Abstract
INTRODUCTION 129Xe ventilation MRI is sensitive to detect early CF lung disease and response to treatment. 129Xe-MRI could play a significant role in clinical trials and patient management. Here we present data on the repeatability of imaging measurements and their sensitivity to longitudinal change. METHODS 29 children and adults with CF and a range of disease severity were assessed twice, a median [IQR] of 16.0 [14.4,19.5] months apart. Patients performed 129Xe-MRI, lung clearance index (LCI), body plethysmography and spirometry at both visits. Eleven patients repeated 129Xe-MRI in the same session to assess the within-visit repeatability. The ventilation defect percentage (VDP) was the primary metric calculated from 129Xe-MRI. RESULTS At baseline, mean (sd) age=23.0 (11.1) years and FEV1 z-score=-2.2 (2.0). Median [IQR] VDP=9.5 [3.4,31.6]%, LCI=9.0 [7.7,13.7]. Within-visit and inter-visit repeatability of VDP was high. At 16 months there was no single trend of 129Xe-MRI disease progression. Visible 129Xe-MRI ventilation changes were common, which reflected changes in VDP. Based on the within-visit repeatability, a significant short-term change in VDP is >±1.6%. For longer-term follow up, changes in VDP of up to ±7.7% can be expected, or ±4.1% for patients with normal FEV1. No patient had a significant change in FEV1, however 59% had change in VDP >±1.6%. In patients with normal FEV1, there were significant changes in ventilation and in VDP. CONCLUSIONS 129Xe-MRI is a highly effective method for assessing longitudinal lung disease in patients with CF. VDP has great potential as a sensitive clinical outcome measure of lung function and endpoint for clinical trials.
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Affiliation(s)
- Laurie J Smith
- POLARIS, Imaging Sciences, Department of Infection Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK
- Sheffield Children's Hospital NHS Foundation Trust, Sheffield, UK
| | - Alex Horsley
- POLARIS, Imaging Sciences, Department of Infection Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK
- Respiratory Research Group, Division of Infection, Immunity & Respiratory Medicine, University of Manchester, Manchester, UK
| | - Jody Bray
- POLARIS, Imaging Sciences, Department of Infection Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK
| | - Paul J C Hughes
- POLARIS, Imaging Sciences, Department of Infection Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK
| | - Alberto Biancardi
- POLARIS, Imaging Sciences, Department of Infection Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK
| | - Graham Norquay
- POLARIS, Imaging Sciences, Department of Infection Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK
| | - Martin Wildman
- Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, UK
| | - Noreen West
- Sheffield Children's Hospital NHS Foundation Trust, Sheffield, UK
| | - Helen Marshall
- POLARIS, Imaging Sciences, Department of Infection Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK
| | - Jim M Wild
- POLARIS, Imaging Sciences, Department of Infection Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK
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31
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Franks LJ, Walsh JR, Hall K, Morris NR. Measuring airway clearance outcomes in bronchiectasis: a review. Eur Respir Rev 2020; 29:190161. [PMID: 32350088 PMCID: PMC9489113 DOI: 10.1183/16000617.0161-2019] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2019] [Accepted: 12/27/2019] [Indexed: 12/21/2022] Open
Abstract
While airway clearance techniques (ACTs) are recommended for individuals with bronchiectasis, many trials have demonstrated inconsistent benefits or failed to reach their primary outcome. This review determined the most common clinical and patient-reported outcome measures used to evaluate the efficacy of ACTs in bronchiectasis. A literature search of five databases using relevant keywords and filtering for studies published in English, up until the end of August 2019, was completed. Studies included randomised controlled trials, using crossover or any other trial design, and abstracts. Studies were included where the control was placebo, no intervention, standard care, usual care or an active comparator. Adults with bronchiectasis not related to cystic fibrosis were included. Extracted data comprised study authors, design, duration, intervention, outcome measures and results. The search identified 27 published studies and one abstract. The most common clinical outcome measures were sputum volume (n=23), lung function (n=17) and pulse oximetry (n=9). The most common patient-reported outcomes were health-related quality of life (measured with St George's Respiratory Questionnaire, n=4), cough-related quality of life (measured with Leicester Cough Questionnaire, n=4) and dyspnoea (measured with Borg/modified Borg scale, n=8). Sputum volume, lung function, dyspnoea and health- and cough-related quality of life appear to be the most common clinical and patient-reported measures of airway clearance treatment efficacy.
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Affiliation(s)
- Lisa J Franks
- Physiotherapy Dept, The Prince Charles Hospital, Chermside, Australia
- School of Allied Health Sciences and Menzies Health Institute, Griffith University, Brisbane, Australia
| | - James R Walsh
- Physiotherapy Dept, The Prince Charles Hospital, Chermside, Australia
- School of Allied Health Sciences and Menzies Health Institute, Griffith University, Brisbane, Australia
- Heart Lung Institute, The Prince Charles Hospital, Chermside, Australia
| | - Kathleen Hall
- Physiotherapy Dept, The Prince Charles Hospital, Chermside, Australia
- Physiotherapy, School of Allied Health, Australian Catholic University, Brisbane, Australia
| | - Norman R Morris
- School of Allied Health Sciences and Menzies Health Institute, Griffith University, Brisbane, Australia
- Heart Lung Institute, The Prince Charles Hospital, Chermside, Australia
- Allied Health Research Collaborative, Metro North Hospital and Health Service, The Prince Charles Hospital, Chermside, Australia
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32
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Sutharsan S, Naehrig S, Mellies U, Sieder C, Ziegler J. An 8 week open-label interventional multicenter study to explore the lung clearance index as endpoint for clinical trials in cystic fibrosis patients ≥8 years of age, chronically infected with Pseudomonas aeruginosa. BMC Pulm Med 2020; 20:167. [PMID: 32532226 PMCID: PMC7291662 DOI: 10.1186/s12890-020-01201-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 05/28/2020] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Forced expiratory volume in 1 second (FEV1) is the only parameter currently recognized as a surrogate endpoint in cystic fibrosis (CF) trials. However, FEV1 is relatively insensitive to changes in the small airways of patients with milder lung disease. This pilot study aimed to explore the lung clearance index (LCI) as a marker for use in efficacy trials with inhaled antibiotics in CF. METHODS This open-label, single-arm study enrolled CF patients with Pseudomonas aeruginosa infection, who were treated with tobramycin (28-day on/off regime). FEV1, LCI and bacterial load in sputum (CFU) were assessed at baseline, after 1, 4 and 8 weeks of treatment. RESULTS All patients (n = 17) showed elevated LCI of > 11 despite 3 patients having normal FEV1 (> 90% predicted) at baseline. Overall, LCI improved in 8 (47%) patients and FEV1 in 9 (53%) patients. At week 4, LCI improved by 0.88, FEV1 increased by 0.52%, and P. aeruginosa reduced by 30,481.3 CFU/mL. These changes were however statistically non-significant. Six adverse events occurred in 5/17 (29.4%) patients, most of which were mild-to-moderate in severity. CONCLUSIONS Due to the low evaluable sample size, no specific trend was observed related to the changes between LCI, FEV1 and CFU. Based on the individual data from this study and from recently published literature, LCI has been shown to be a more sensitive parameter than FEV1 for lung function. LCI can be hypothesized to be an appropriate endpoint for efficacy trials in CF patients if the heterogeneity in lung function is limited by enrolling younger patients or patients with more milder lung disease and thus, limiting the ventilation inhomogeneities. TRIAL REGISTRATION The study is registered with ClinicalTrials.gov, identifier: NCT02248922.
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Affiliation(s)
- Sivagurunathan Sutharsan
- Division for Cystic Fibrosis, Department of Pulmonary Medicine, University Medicine Essen - Ruhrlandklinik, Essen, Germany.
| | - Susanne Naehrig
- Cystic Fibrosis Center for Adults, University Hospital Munich, Med. Klinik V, Munich, Germany
| | - Uwe Mellies
- Pediatric Pulmonology and Sleep Medicine, Children's Hospital, University of Duisburg-Essen, Essen, Germany
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Alobaidi NY, Stockley JA, Stockley RA, Sapey E. An overview of exacerbations of chronic obstructive pulmonary disease: Can tests of small airways' function guide diagnosis and management? Ann Thorac Med 2020; 15:54-63. [PMID: 32489439 PMCID: PMC7259399 DOI: 10.4103/atm.atm_323_19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 12/20/2019] [Indexed: 12/14/2022] Open
Abstract
Chronic obstructive pulmonary disease (COPD) is common and debilitating. Most patients with COPD experience intermittent, acute deterioration in symptoms which require additional therapy, termed exacerbations. Exacerbations are prevalent in COPD and are associated with poor clinical outcomes including death, a faster decline in lung health, and a reduced quality of life. Current guidelines highlight the need to treat exacerbations promptly and then mitigate future risk. However, exacerbations are self-reported, difficult to diagnose and are treated with pharmacological therapies which have largely been unchanged over 30 years. Recent research has highlighted how exacerbations vary in their underlying cause, with specific bacteria, viruses, and cell types implicated. This variation offers the opportunity for new targeted therapies, but to develop these new therapies requires sensitive tools to reliably identify the cause, the start, and end of an exacerbation and assess the response to treatment. Currently, COPD is diagnosed and monitored using spirometric measures, principally the forced expiratory volume in 1 s and forced vital capacity, but these tests alone cannot reliably diagnose an exacerbation. Measures of small airways' function appear to be an early marker of COPD, and some studies have suggested that these tests might also provide physiological biomarkers for exacerbations. In this review, we will discuss how exacerbations of COPD are currently defined, stratified, monitored, and treated and review the current literature to determine if tests of small airways' function might improve diagnostic accuracy or the assessment of response to treatment.
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Affiliation(s)
- Nowaf Y Alobaidi
- Centre for Translational Inflammation Research, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK.,Respiratory Therapy Department, College of Applied Medical Sciences, King Saud Bin Abdul-Aziz University for Health Sciences, Al Ahsa, Saudi Arabia
| | - James A Stockley
- Department of Lung Function and Sleep, University Hospitals Birmingham, NHS Foundation Trust, Birmingham, UK
| | - Robert A Stockley
- Department of Respiratory Medicine, University Hospitals Birmingham, NHS Foundation Trust, Birmingham, UK
| | - Elizabeth Sapey
- Centre for Translational Inflammation Research, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
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Calprotectin as a New Sensitive Marker of Neutrophilic Inflammation in Patients with Bronchiolitis Obliterans. Mediators Inflamm 2020; 2020:4641585. [PMID: 32410855 PMCID: PMC7211255 DOI: 10.1155/2020/4641585] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Revised: 03/10/2020] [Accepted: 04/04/2020] [Indexed: 11/18/2022] Open
Abstract
Introduction Bronchiolitis obliterans (BO) is a chronic disease in which persistent inflammation leads to obstruction and obliteration of the small airways. The aim of this study was to evaluate the value of calprotectin as an inflammatory marker in induced sputum. Methods Twenty-eight patients suffering from BO and 18 healthy controls were examined. Lung function was measured by spirometry, body plethysmography, and lung clearance index (LCI). The induced sputum was obtained, cell counts were performed, and cytokines were measured using cytometric bead array (CBA). Calprotectin was quantified in the sputum and serum samples using commercially available sandwich ELISA. Results Spirometry parameters including forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and maximum expiratory flow rate at 25% vital capacity (MEF25) were significantly lower in BO patients than in healthy controls, whereas the reserve volume (RV), RV to total lung capacity ratio (RV/TLC), and LCI were significantly increased. In sputum, calprotectin levels, neutrophils, and IL-8 were significantly elevated. Calprotectin levels correlated strongly with IL-8 and other biomarkers, neutrophils FEV1 and MEF25. In serum, calprotectin was significantly diminished in BO patients compared to controls. Conclusion Lung function is severely impaired in BO patients. Calprotectin is significantly elevated in the sputum of BO patients and reflects ongoing neutrophilic inflammation.
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Irving S, Fleming L, Ahmad F, Biggart E, Bingham Y, Cook J, Hall P, Jamalzadeh A, Nagakumar P, Bossley C, Gupta A, Macleod K, Saglani S, Bush A. Lung clearance index and steroid response in pediatric severe asthma. Pediatr Pulmonol 2020; 55:890-898. [PMID: 32027471 DOI: 10.1002/ppul.24675] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 01/19/2020] [Indexed: 11/06/2022]
Abstract
INTRODUCTION Lung clearance index (LCI) is a measure of airway disease that has been shown to be abnormal in asthma. We hypothesized that LCI would be higher (worse) in children with severe therapy-resistant asthma (STRA) compared with difficult asthma (DA) and healthy controls and that LCI would fall in response to parenteral steroids in STRA. METHODS Sixty-four children with asthma who were prescribed high-dose asthma therapy (GINA steps 4 or 5) performed LCI and spirometry. Forty-three had STRA and 21 DA. Thirty-nine of forty-three STRA patients attended for a clinically indicated bronchoscopy during which an intramuscular injection of triamcinolone was given. LCI, spirometry, and fractional exhaled nitric oxide (FeNO) were performed on the day of the bronchoscopy and repeated 4 weeks later. RESULTS LCI was more abnormal in STRA (median: 7.40, range: 5.58-12.34) than in DA (6.55, 5.77-7.75), P = .0006, and healthy controls (6.53, 5.57-7.35), P = .005. In contrast to the first second forced expired volume (FEV1 ), LCI improved following systemic steroids; of 20 STRA patients with an abnormal LCI at baseline, 13 improved following triamcinolone. LCI and FeNO responses were concordant. CONCLUSIONS There is a subgroup of children with STRA in whom LCI is elevated who improve following parenteral steroids. LCI may be a valuable additional domain in assessing steroid response in pediatric asthma.
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Affiliation(s)
- Samantha Irving
- Royal Brompton and Harefield NHS Foundation Trust, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK
| | - Louise Fleming
- Royal Brompton and Harefield NHS Foundation Trust, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK
| | - Fatima Ahmad
- National Heart and Lung Institute, Imperial College London, London, UK
| | | | - Yvvone Bingham
- National Heart and Lung Institute, Imperial College London, London, UK
| | - James Cook
- Royal Brompton and Harefield NHS Foundation Trust, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK
| | - Pippa Hall
- Royal Brompton and Harefield NHS Foundation Trust, London, UK
| | | | - Prasad Nagakumar
- Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Cara Bossley
- King's College Hospital NHS Trust, London, UK.,Child Health Clinical Academic Group, King's College, London, UK
| | - Atul Gupta
- King's College Hospital NHS Trust, London, UK.,Child Health Clinical Academic Group, King's College, London, UK
| | | | - Sejal Saglani
- Royal Brompton and Harefield NHS Foundation Trust, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK
| | - Andrew Bush
- Royal Brompton and Harefield NHS Foundation Trust, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK
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Horsley AR, Alrumuh A, Bianco B, Bayfield K, Tomlinson J, Jones A, Maitra A, Cunningham S, Smith J, Fullwood C, Pandyan A, Gilchrist FJ. Lung clearance index in healthy volunteers, measured using a novel portable system with a closed circuit wash-in. PLoS One 2020; 15:e0229300. [PMID: 32097445 PMCID: PMC7041809 DOI: 10.1371/journal.pone.0229300] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 02/03/2020] [Indexed: 11/18/2022] Open
Abstract
Introduction Lung clearance index (LCI) is a sensitive measure of early lung disease, but adoption into clinical practice has been slow. Challenges include the time taken to perform each test. We recently described a closed-circuit inert gas wash-in method that reduces overall testing time by decreasing the time to equilibration. The aim of this study was to define a normative range of LCI in healthy adults and children derived using this method. We were also interested in the feasibility of using this system to measure LCI in a community setting. Methods LCI was assessed in healthy volunteers at three hospital sites and in two local primary schools. Volunteers completed three washout repeats at a single visit using the closed circuit wash-in method (0.2% SF6 wash-in tracer gas to equilibrium, room air washout). Results 160 adult and paediatric subjects successfully completed LCI assessment (95%) (100 in hospital, 60 in primary schools). Median coefficient of variation was 3.4% for LCI repeats and 4.3% for FRC. Mean (SD) LCI for the analysis cohort (n = 53, age 5–39 years) was 6.10 (0.42), making the upper limit of normal LCI 6.8. There was no relationship between LCI and multiple demographic variables. Median (interquartile range) total test time was 18.7 (16.0–22.5) minutes. Conclusion The closed circuit method of LCI measurement can be successfully and reproducibly measured in healthy volunteers, including in out-of-hospital settings. Normal range appears stable up to 39 years. With few subjects older than 40 years, further work is required to define the normal limits above this age.
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Affiliation(s)
- Alex R. Horsley
- Division of Infection, Immunity & Respiratory Medicine, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom
- Manchester Adult CF Centre, Manchester University NHS Foundation Trust, Manchester, United Kingdom
- * E-mail:
| | - Amnah Alrumuh
- Institute of Applied Clinical Science, Keele University, Newcastle-under-Lyme, United Kingdom
- Royal Stoke University Hospital, University Hospitals of North Midlands NHS Trust, Stoke-on-Trent, United Kingdom
| | - Brooke Bianco
- Manchester Adult CF Centre, Manchester University NHS Foundation Trust, Manchester, United Kingdom
- NIHR Manchester Clinical Research Facility, Manchester, United Kingdom
| | - Katie Bayfield
- NIHR Manchester Clinical Research Facility, Manchester, United Kingdom
| | - Joanne Tomlinson
- Royal Stoke University Hospital, University Hospitals of North Midlands NHS Trust, Stoke-on-Trent, United Kingdom
| | - Andrew Jones
- Division of Infection, Immunity & Respiratory Medicine, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom
- Manchester Adult CF Centre, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Anirban Maitra
- Royal Manchester Children’s Hospital, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Steve Cunningham
- Centre for Inflammation Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Jaclyn Smith
- Division of Infection, Immunity & Respiratory Medicine, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Catherine Fullwood
- Research and Innovation, Manchester University NHS Foundation Trust, Manchester, United Kingdom
- Centre for Biostatistics, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Anand Pandyan
- Institute of Applied Clinical Science, Keele University, Newcastle-under-Lyme, United Kingdom
| | - Francis J. Gilchrist
- Institute of Applied Clinical Science, Keele University, Newcastle-under-Lyme, United Kingdom
- Royal Stoke University Hospital, University Hospitals of North Midlands NHS Trust, Stoke-on-Trent, United Kingdom
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Trinkmann F, Lenz SA, Schäfer J, Gawlitza J, Schroeter M, Gradinger T, Akin I, Borggrefe M, Ganslandt T, Saur J. Feasibility and clinical applications of multiple breath wash-out (MBW) testing using sulphur hexafluoride in adults with bronchial asthma. Sci Rep 2020; 10:1527. [PMID: 32001782 PMCID: PMC6992773 DOI: 10.1038/s41598-020-58538-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 01/15/2020] [Indexed: 11/17/2022] Open
Abstract
Ventilation heterogeneity is frequent in bronchial asthma and can be assessed using multiple breath wash-out testing (MBW). Most data is available in paediatric patients and using nitrogen as a tracer gas. We aimed to evaluate sulphur hexafluoride (SF6) MBW in adult asthmatics. Spirometry, whole-body plethysmography, impulse oscillometry and SF6-MBW were prospectively performed. MBW parameters reflecting global (lung clearance index, LCI), acinar (Sacin) and conductive (Scond) ventilation heterogeneity were derived from three consecutive wash-outs. LCI was calculated for the traditional 2.5% and an earlier 5% stopping point that has the potential to reduce wash-out times. 91 asthmatics (66%) and 47 non-asthmatic controls (34%) were included in final analysis. LCI2.5 and LCI5 were higher in asthmatics (p < 0.001). Likewise, Sacin and Scond were elevated (p < 0.001 and p < 0.01). Coefficient of variation was 3.4% for LCI2.5 and 3.5% for LCI5 in asthmatics. Forty-one asthmatic patients had normal spirometry. ROC analysis revealed an AUC of 0.906 for the differentiation from non-asthmatic controls exceeding diagnostic performance of individual and conventional parameters (AUC = 0.819, p < 0.05). SF6-MBW is feasible and reproducible in adult asthmatics. Ventilation heterogeneity is increased as compared to non-asthmatic controls persisting in asthmatic patients with normal spirometry. Diagnostic performance is not affected using an earlier LCI stopping point while reducing wash-out duration considerably.
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Affiliation(s)
- Frederik Trinkmann
- 1st Department of Medicine (Cardiology, Angiology, Pulmonary and Intensive Care), University Medical Centre Mannheim, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany. .,Department of Biomedical Informatics of the Heinrich-Lanz-Centre, University Medical Centre Mannheim, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany.
| | - Steffi A Lenz
- 1st Department of Medicine (Cardiology, Angiology, Pulmonary and Intensive Care), University Medical Centre Mannheim, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
| | - Julia Schäfer
- 1st Department of Medicine (Cardiology, Angiology, Pulmonary and Intensive Care), University Medical Centre Mannheim, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
| | - Joshua Gawlitza
- Institute of Clinical Radiology and Nuclear Medicine, University Medical Centre Mannheim, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
| | - Michele Schroeter
- 1st Department of Medicine (Cardiology, Angiology, Pulmonary and Intensive Care), University Medical Centre Mannheim, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
| | - Tobias Gradinger
- Department of Biomedical Informatics of the Heinrich-Lanz-Centre, University Medical Centre Mannheim, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
| | - Ibrahim Akin
- 1st Department of Medicine (Cardiology, Angiology, Pulmonary and Intensive Care), University Medical Centre Mannheim, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Mannheim, University Medical Centre Mannheim, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
| | - Martin Borggrefe
- 1st Department of Medicine (Cardiology, Angiology, Pulmonary and Intensive Care), University Medical Centre Mannheim, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Mannheim, University Medical Centre Mannheim, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
| | - Thomas Ganslandt
- Department of Biomedical Informatics of the Heinrich-Lanz-Centre, University Medical Centre Mannheim, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
| | - Joachim Saur
- 1st Department of Medicine (Cardiology, Angiology, Pulmonary and Intensive Care), University Medical Centre Mannheim, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
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Nuttall AGL, Velásquez W, Beardsmore CS, Gaillard EA. Lung clearance index: assessment and utility in children with asthma. Eur Respir Rev 2019; 28:28/154/190046. [PMID: 31748419 DOI: 10.1183/16000617.0046-2019] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 07/26/2019] [Indexed: 11/05/2022] Open
Abstract
There is increasing evidence that ventilation heterogeneity and small airway disease are significant factors in asthma, with evidence suggesting that the small airways are involved from an early stage in childhood asthma. Spirometry is commonly used to monitor lung function in asthmatics; however, it is not sensitive to small airway disease. There has been renewed interest in multibreath washout (MBW) tests, with recognition of the lung clearance index (LCI) as a global index of abnormality in gas mixing of the lungs that therefore also reflects small airway disease. This review summarises the technical and practical aspects of the MBW/LCI in children, and the differences between commercially available equipment. Children with severe asthma are more likely to have an abnormal LCI, whereas most children with mild-to-moderate asthma have an LCI within the normal range, but slightly higher than age-matched healthy controls. Monitoring children with asthma with MBW alongside standard spirometry may provide useful additional information.
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Affiliation(s)
- Amy G L Nuttall
- Institute for Lung Health, NIHR Leicester Respiratory Biomedical Research Unit and Dept of Infection Immunity and Inflammation, University of Leicester, Leicester, UK.,Children's Hospital, University Hospitals Leicester, Leicester, UK
| | - Werner Velásquez
- Hospital de Especialidades Rodolfo Robles, Quetzaltenango, Guatemala
| | - Caroline S Beardsmore
- Institute for Lung Health, NIHR Leicester Respiratory Biomedical Research Unit and Dept of Infection Immunity and Inflammation, University of Leicester, Leicester, UK.,Children's Hospital, University Hospitals Leicester, Leicester, UK
| | - Erol A Gaillard
- Institute for Lung Health, NIHR Leicester Respiratory Biomedical Research Unit and Dept of Infection Immunity and Inflammation, University of Leicester, Leicester, UK .,Children's Hospital, University Hospitals Leicester, Leicester, UK
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Imaging Lung Function Abnormalities in Primary Ciliary Dyskinesia Using Hyperpolarized Gas Ventilation MRI. Ann Am Thorac Soc 2019; 15:1487-1490. [PMID: 29684285 DOI: 10.1513/annalsats.201711-890rl] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Bayfield KJ, Horsley A, Alton E, Irving S, Bush A, Davies JC. Simultaneous sulfur hexafluoride and nitrogen multiple-breath washout (MBW) to examine inherent differences in MBW outcomes. ERJ Open Res 2019; 5:00234-2018. [PMID: 31720295 PMCID: PMC6826248 DOI: 10.1183/23120541.00234-2018] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Accepted: 08/27/2019] [Indexed: 11/10/2022] Open
Abstract
Multiple-breath washout (MBW) can be performed with different gases (sulfur hexafluoride (SF6) and nitrogen (N2)) and different devices, all of which give discrepant results. This study aimed to confirm previously reported differences and explore factors influencing discrepant results; equipment factors or the physical properties of gases used. Inherent differences in simultaneous SF6 and N2 washout on the mass spectrometer show why results are never comparablehttp://bit.ly/34k52Oo
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Affiliation(s)
- Katie J Bayfield
- Imperial College London, London, UK.,Royal Brompton and Harefield NHS Foundation Trust, London, UK.,European Cystic Fibrosis Society Clinical Trials Network, Lung Clearance Index Core Facility, London, UK.,The Children's Hospital at Westmead, Sydney, Australia
| | - Alex Horsley
- Institute of Inflammation and repair, Education and Research centre, University of Manchester, University Hospital of South Manchester, Manchester, UK
| | - Eric Alton
- Imperial College London, London, UK.,Royal Brompton and Harefield NHS Foundation Trust, London, UK
| | - Samantha Irving
- Imperial College London, London, UK.,Royal Brompton and Harefield NHS Foundation Trust, London, UK
| | - Andrew Bush
- Imperial College London, London, UK.,Royal Brompton and Harefield NHS Foundation Trust, London, UK
| | - Jane C Davies
- Imperial College London, London, UK.,Royal Brompton and Harefield NHS Foundation Trust, London, UK.,European Cystic Fibrosis Society Clinical Trials Network, Lung Clearance Index Core Facility, London, UK
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Driskel M, Horsley A, Fretwell L, Clayton N, Al-Aloul M. Lung clearance index in detection of post-transplant bronchiolitis obliterans syndrome. ERJ Open Res 2019; 5:00164-2019. [PMID: 31637252 PMCID: PMC6791965 DOI: 10.1183/23120541.00164-2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 08/16/2019] [Indexed: 11/05/2022] Open
Abstract
Background Long-term outcomes after lung transplantation are often limited by the development of obliterative bronchiolitis (OB), which is clinically defined using spirometry as bronchiolitis obliterans syndrome (BOS). Lung clearance index (LCI), derived from multiple breath washout (MBW) testing, is a global measure of ventilation heterogeneity that has previously been shown to be a more sensitive measure of obstructive small airway diseases than spirometry. We aimed to assess the feasibility of LCI in adult lung transplant patients and to compare LCI to BOS grade. Methods 51 stable adult double-lung transplant recipients performed sulfur hexafluoride MBW in triplicate on a single occasion, using a closed-circuit Innocor device. BOS grades were derived from serial spirometry according to International Society for Heart and Lung Transplantation criteria and, where available, high-resolution computed tomography (HRCT) evidence of OB was recorded. Results LCI was successfully performed in 98% of patients. The within-visit coefficient of variation for repeat LCI measurements was 3.1%. Mean LCI increased significantly with BOS grades: no BOS (n=15), LCI 7.6; BOS-0p (n=16), LCI 8.3; BOS-1 (n=11), LCI 9.3; BOS-2-3 (n=9), LCI 13.2 (p<0.001). 27 patients had HRCT within 12 months. LCI in those with HRCT evidence of OB was higher than those without OB (11.1 versus 8.2, p=0.006). 47% patients displayed abnormal LCI (>7) despite a normal forced expiratory volume in 1 s (FEV1) (>80% of baseline). Conclusions LCI measurement in lung transplant recipients is feasible and reproducible. LCI increased with increasing BOS grade. A significant proportion of this cohort had abnormal LCI with preserved FEV1, suggesting early subclinical small airway dysfunction, and supporting a role for MBW in the early identification of BOS.
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Affiliation(s)
- Madeleine Driskel
- Lung Function Laboratory, Manchester University NHS Foundation Trust, Manchester, UK.,Cardiothoracic Transplant Unit, Manchester University NHS Foundation Trust, Manchester, UK
| | - Alex Horsley
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | | | - Nigel Clayton
- Lung Function Laboratory, Manchester University NHS Foundation Trust, Manchester, UK
| | - Mohamed Al-Aloul
- Cardiothoracic Transplant Unit, Manchester University NHS Foundation Trust, Manchester, UK
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Shanthikumar S, Neeland MN, Saffery R, Ranganathan S. Gene modifiers of cystic fibrosis lung disease: A systematic review. Pediatr Pulmonol 2019; 54:1356-1366. [PMID: 31140758 DOI: 10.1002/ppul.24366] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 05/03/2019] [Accepted: 05/05/2019] [Indexed: 12/16/2022]
Abstract
BACKGROUND Lung disease is the major source of morbidity and mortality in cystic fibrosis (CF), with large variability in severity between patients. Although accurate prediction of lung disease severity would be extremely useful, no robust methods exist. Twin and sibling studies have highlighted the importance of non-cystic fibrosis transmembrane conductance regulator (CFTR) genes in determining lung disease severity but how these impact on the severity in CF remains unclear. METHODS A systematic review was undertaken to answer the question "In patients with CF which non-CFTR genes modify the severity of lung disease?" The method for this systematic review was based upon the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)" statement, with a narrative synthesis of results planned. RESULTS A total of 1168 articles were screened for inclusion, with 275 articles undergoing detailed assessment for inclusion. One hundred and forty articles were included. Early studies focused on candidate genes, whereas more recent studies utilized genome-wide approaches and also examined epigenetic mechanisms, gene expression, and therapeutic response. DISCUSSION A large body of evidence regarding non-CFTR gene modifiers of lung disease severity has been generated, examining a wide array of genes. Limitations to existing studies include heterogeneity in outcome measures used, limited replication, and relative lack of clinical impact. Future work examining non-CFTR gene modifiers will have to overcome these limitations if gene modifiers are to have a meaningful role in the care of patients with CF.
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Affiliation(s)
- Shivanthan Shanthikumar
- Respiratory and Sleep Medicine Department, Royal Children's Hospital, Melbourne, Australia.,Respiratory Diseases Department, Murdoch Children's Research Institute, Melbourne, Australia.,Department of Paediatrics, The University of Melbourne, Australia
| | - Melanie N Neeland
- Department of Paediatrics, The University of Melbourne, Australia.,Centre of Food and Allergy Research, Murdoch Children's Research Institute, Melbourne, Australia
| | - Richard Saffery
- Department of Paediatrics, The University of Melbourne, Australia.,Cancer & Disease Epigenetics, Murdoch Children's Research Institute, Melbourne, Australia
| | - Sarath Ranganathan
- Respiratory and Sleep Medicine Department, Royal Children's Hospital, Melbourne, Australia.,Respiratory Diseases Department, Murdoch Children's Research Institute, Melbourne, Australia.,Department of Paediatrics, The University of Melbourne, Australia
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Shawcross A, Murray CS, Pike K, Horsley A. A novel method for infant multiple breath washout: First report in clinical practice. Pediatr Pulmonol 2019; 54:1284-1290. [PMID: 31211518 DOI: 10.1002/ppul.24384] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2018] [Revised: 11/23/2018] [Accepted: 11/30/2018] [Indexed: 11/09/2022]
Abstract
BACKGROUND Lung clearance index (LCI), measured using multiple breath inert gas washout (MBW) is a potentially useful test in infants with respiratory disease, particularly cystic fibrosis (CF). Clinical use is limited however by the need for specialist staff and equipment. We have previously described a novel method for infant MBW suitable for use outside of specialist laboratories. This study describes its performance in vivo in infants with CF and healthy controls, including a limited comparison with the respiratory mass spectrometer. METHODS Children aged less than 2 years with CF and controls underwent MBW testing on a single occasion. The practical applicability of the system was determined by the number of successful duplicate tests and within-subject repeatability. RESULTS Twenty-five children (seven with CF, 18 healthy controls, all sedated with chloral hydrate) attempted MBW. Twenty patients (seven with CF) successfully underwent duplicate testing (80% success rate). Mean within-subject coefficient of variation for functional residual capacity (FRC) was 7.2% and for LCI 5.9%. Comparison of LCI with the mass spectrometer was limited but gave very similar values for LCI and FRC in those patients who underwent technically adequate tests with both methods. CONCLUSIONS We have described a new MBW method that is feasible and reproducible in sedated infants. Results fall within the expected range, and well within accuracy limits set by international guidelines. This could provide a more accessible alternative to previously described systems for infant MBW, and overcomes many of the technical challenges inherent in conventional MBW.
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Affiliation(s)
- Anna Shawcross
- Division of Infection, Immunity & Respiratory Medicine, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.,Department of Paediatric Respiratory Medicine, Royal Manchester Children's Hospital, Manchester, UK
| | - Clare S Murray
- Division of Infection, Immunity & Respiratory Medicine, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.,Department of Paediatric Respiratory Medicine, Royal Manchester Children's Hospital, Manchester, UK
| | - Katy Pike
- UCL Great Ormond Street Institute of Child Health, University College London, London, UK.,Department of Paediatric Respiratory Medicine, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Alex Horsley
- Division of Infection, Immunity & Respiratory Medicine, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.,Manchester Adult Cystic Fibrosis Centre, Manchester University Hospitals NHS Foundation Trust, Manchester, UK
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44
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O'Neill K, Einarsson GG, Rowan S, McIlreavey L, Lee AJ, Lawson J, Lynch T, Horsley A, Bradley JM, Elborn JS, Tunney MM. Composition of airway bacterial community correlates with chest HRCT in adults with bronchiectasis. Respirology 2019; 25:64-70. [DOI: 10.1111/resp.13653] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 05/15/2019] [Accepted: 06/18/2019] [Indexed: 12/21/2022]
Affiliation(s)
- Katherine O'Neill
- Wellcome‐Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical SciencesQueen's University Belfast Belfast UK
| | - Gisli G. Einarsson
- Wellcome‐Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical SciencesQueen's University Belfast Belfast UK
| | - Stephen Rowan
- South Eastern Health and Social Care Trust Belfast UK
| | | | - Andrew J. Lee
- Wellcome‐Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical SciencesQueen's University Belfast Belfast UK
| | - John Lawson
- Belfast Health and Social Care Trust Belfast UK
| | - Tom Lynch
- Belfast Health and Social Care Trust Belfast UK
| | - Alex Horsley
- Division of Infection, Immunity and Respiratory MedicineUniversity of Manchester Manchester UK
| | - Judy M. Bradley
- Wellcome‐Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical SciencesQueen's University Belfast Belfast UK
| | - J. Stuart Elborn
- Wellcome‐Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical SciencesQueen's University Belfast Belfast UK
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45
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Robinson PD, Latzin P, Ramsey KA, Stanojevic S, Aurora P, Davis SD, Gappa M, Hall GL, Horsley A, Jensen R, Lum S, Milla C, Nielsen KG, Pittman JE, Rosenfeld M, Singer F, Subbarao P, Gustafsson PM, Ratjen F. Preschool Multiple-Breath Washout Testing. An Official American Thoracic Society Technical Statement. Am J Respir Crit Care Med 2019; 197:e1-e19. [PMID: 29493315 DOI: 10.1164/rccm.201801-0074st] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND Obstructive airway disease is nonuniformly distributed throughout the bronchial tree, although the extent to which this occurs can vary among conditions. The multiple-breath washout (MBW) test offers important insights into pediatric lung disease, not available through spirometry or resistance measurements. The European Respiratory Society/American Thoracic Society inert gas washout consensus statement led to the emergence of validated commercial equipment for the age group 6 years and above; specific recommendations for preschool children were beyond the scope of the document. Subsequently, the focus has shifted to MBW applications within preschool subjects (aged 2-6 yr), where a "window of opportunity" exists for early diagnosis of obstructive lung disease and intervention. METHODS This preschool-specific technical standards document was developed by an international group of experts, with expertise in both custom-built and commercial MBW equipment. A comprehensive review of published evidence was performed. RESULTS Recommendations were devised across areas that place specific age-related demands on MBW systems. Citing evidence where available in the literature, recommendations are made regarding procedures that should be used to achieve robust MBW results in the preschool age range. The present work also highlights the important unanswered questions that need to be addressed in future work. CONCLUSIONS Consensus recommendations are outlined to direct interested groups of manufacturers, researchers, and clinicians in preschool device design, test performance, and data analysis for the MBW technique.
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46
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Anagnostopoulou P, Vomsattel S, Kentgens AC, Guidi M, Binggeli S, Kohler L, Singer F, Latzin P, Obrist D. An innovative lung model for multiple breath washout testing in health and disease. Clin Biomech (Bristol, Avon) 2019; 66:74-80. [PMID: 29157654 DOI: 10.1016/j.clinbiomech.2017.11.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 11/02/2017] [Accepted: 11/06/2017] [Indexed: 02/07/2023]
Abstract
BACKGROUND Multiple breath washout (MBW) is a lung function test that identifies the degree of ventilation inhomogeneity (VI) in the lungs. In vitro validation of MBW devices is recommended. So far, plastic lung models for MBW validation ignored variable degrees of VI. Our primary aim was to create a plastic lung model applicable for physiological lung volumes and variable VI. METHODS A plastic box divided in two chambers was filled with water and ventilated in various lung volumes and respiratory rates. A ventilator was used for efficient gas distribution (model with low VI). An additional divider was inserted to create a model with high VI. The model was connected to commercial MBW devices and measurements were performed using different tracer gases and conditions. Primary outcome was the precision of generated functional residual capacity (FRC) and the ability to generate variable VI. The latter was estimated by lung clearance index (LCI) and expiratory phase III slopes (SIII). LCI was also compared to a mathematical model. FINDINGS The intra-test variability for FRC was minimal, mean(SD) coefficient of variation 0.96(0.63)%, using different tracer gases under different conditions. Compared to the model with low VI, in the model with high VI LCI and washout SIII were significantly increased. LCI compared well to the mathematical model. INTERPRETATION This novel lung model shows excellent precision in lung volumes and VI estimates independent of tracer gases and conditions. The model can mimic the lungs of patients with uneven gas distribution.
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Affiliation(s)
- Pinelopi Anagnostopoulou
- Pediatric Respiratory Medicine, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Switzerland.
| | - Sarah Vomsattel
- Pediatric Respiratory Medicine, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Switzerland
| | - Anne-Christiane Kentgens
- Pediatric Respiratory Medicine, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Switzerland; Department of Respiratory Medicine and Allergy, Radboud University Medical Centre, Amalia Children's Hospital, Nijmegen, Netherlands
| | - Marisa Guidi
- Pediatric Respiratory Medicine, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Switzerland
| | - Severin Binggeli
- Pediatric Respiratory Medicine, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Switzerland
| | - Lena Kohler
- Pediatric Respiratory Medicine, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Switzerland
| | - Florian Singer
- Pediatric Respiratory Medicine, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Switzerland
| | - Philipp Latzin
- Pediatric Respiratory Medicine, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Switzerland
| | - Dominik Obrist
- ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland
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47
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Walkup LL, Myers K, El-Bietar J, Nelson A, Willmering MM, Grimley M, Davies SM, Towe C, Woods JC. Xenon-129 MRI detects ventilation deficits in paediatric stem cell transplant patients unable to perform spirometry. Eur Respir J 2019; 53:1801779. [PMID: 30846475 PMCID: PMC6945824 DOI: 10.1183/13993003.01779-2018] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 02/06/2019] [Indexed: 12/14/2022]
Abstract
BACKGROUND Early detection of pulmonary morbidity following haematopoietic stem cell transplantation (HSCT) remains an important challenge for intervention, primarily due to the insensitivity of spirometry to early change, and in paediatrics, patient compliance provides additional challenges. Regional lung ventilation abnormalities in paediatric HSCT patients were quantified using hyperpolarised xenon-129 (129Xe) magnetic resonance imaging (MRI) and compared to spirometry. METHODS Medically stable, paediatric allogeneic HSCT patients (n=23, ages 6-16 years) underwent an outpatient MRI scan where regional ventilation was quantified with a breath-hold of hyperpolarised 129Xe gas. Ventilation deficits, regions of the lung that ventilate poorly due to obstruction, were quantified as a ventilation defect percentage (VDP) and compared to forced expiratory volume in 1 s (FEV1), FEV1/forced vital capacity (FVC) ratio, and forced expiratory flow at 25-75% of FVC (FEF25-75%) from spirometry using linear regression. RESULTS The mean±sd 129Xe VDP was 10.5±9.4% (range 2.6-41.4%). 129Xe VDP correlated with FEV1, FEV1/FVC ratio and FEF25-75% (p≤0.02 for all comparisons). Ventilation deficits were detected in patients with normal spirometry (i.e. FEV1 >80%), supporting the sensitivity of 129Xe MRI to early obstruction reported in other pulmonary conditions. Seven (30%) patients could not perform spirometry, yet ventilation deficits were observed in five of these patients, detecting abnormalities that otherwise may have gone undetected and untreated until advanced. CONCLUSION Lung ventilation deficits were detected using hyperpolarised 129Xe gas MRI in asymptomatic paediatric HSCT patients and in a subgroup who were unable to perform reliable spirometry. 129Xe MRI provides a reliable imaging-based assessment of pulmonary involvement in this potentially difficult to diagnose paediatric population.
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Affiliation(s)
- Laura L Walkup
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Dept of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Dept of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, OH, USA
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Kasiani Myers
- Dept of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, OH, USA
- Division of Bone Marrow Transplantation and Immune Deficiency, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Javier El-Bietar
- Dept of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, OH, USA
- Division of Bone Marrow Transplantation and Immune Deficiency, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Deceased 19 December 2017
| | - Adam Nelson
- Dept of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, OH, USA
- Division of Bone Marrow Transplantation and Immune Deficiency, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Matthew M Willmering
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Dept of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Michael Grimley
- Dept of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, OH, USA
- Division of Bone Marrow Transplantation and Immune Deficiency, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Stella M Davies
- Dept of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, OH, USA
- Division of Bone Marrow Transplantation and Immune Deficiency, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Christopher Towe
- Dept of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, OH, USA
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Jason C Woods
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Dept of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Dept of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, OH, USA
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
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48
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Petousi N, Talbot NP, Pavord I, Robbins PA. Measuring lung function in airways diseases: current and emerging techniques. Thorax 2019; 74:797-805. [PMID: 31036773 DOI: 10.1136/thoraxjnl-2018-212441] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 02/14/2019] [Accepted: 02/25/2019] [Indexed: 12/12/2022]
Abstract
Chronic airways diseases, including asthma, COPD and cystic fibrosis, cause significant morbidity and mortality and are associated with high healthcare expenditure, in the UK and worldwide. For patients with these conditions, improvements in clinical outcomes are likely to depend on the application of precision medicine, that is, the matching of the right treatment to the right patient at the right time. In this context, the identification and targeting of 'treatable traits' is an important priority in airways disease, both to ensure the appropriate use of existing treatments and to facilitate the development of new disease-modifying therapy. This requires not only better understanding of airway pathophysiology but also an enhanced ability to make physiological measurements of disease activity and lung function and, if we are to impact on the natural history of these diseases, reliable measures in early disease. In this article, we outline some of the key challenges faced by the respiratory community in the management of airways diseases, including early diagnosis, disease stratification and monitoring of therapeutic response. In this context, we review the advantages and limitations of routine physiological measurements of respiratory function including spirometry, body plethysmography and diffusing capacity and discuss less widely used methods such as forced oscillometry, inert gas washout and the multiple inert gas elimination technique. Finally, we highlight emerging technologies including imaging methods such as quantitative CT and hyperpolarised gas MRI as well as quantification of lung inhomogeneity using precise in-airway gas analysis and mathematical modelling. These emerging techniques have the potential to enhance existing measures in the assessment of airways diseases, may be particularly valuable in early disease, and should facilitate the efforts to deliver precision respiratory medicine.
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Affiliation(s)
- Nayia Petousi
- Nuffield Department of Clinical Medicine Division of Experimental Medicine, University of Oxford, Oxford, UK .,Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK.,Oxford Centre for Respiratory Medicine, Oxford University Hospitals NHS Trust, Oxford, UK
| | - Nick P Talbot
- Nuffield Department of Clinical Medicine Division of Experimental Medicine, University of Oxford, Oxford, UK.,Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK.,Oxford Centre for Respiratory Medicine, Oxford University Hospitals NHS Trust, Oxford, UK
| | - Ian Pavord
- Nuffield Department of Clinical Medicine Division of Experimental Medicine, University of Oxford, Oxford, UK.,Oxford Centre for Respiratory Medicine, Oxford University Hospitals NHS Trust, Oxford, UK
| | - Peter A Robbins
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
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49
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Colombo C, Alicandro G, Gambazza S, Mileto P, Mari A, Grespan E, Nazzari E, Russo MC, Battezzati A. Ventilation inhomogeneity is associated with OGTT-derived insulin secretory defects in cystic fibrosis. Pediatr Pulmonol 2019; 54:141-149. [PMID: 30575293 DOI: 10.1002/ppul.24212] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 11/09/2018] [Indexed: 12/24/2022]
Abstract
Progressive deterioration of β-cell function is the main mechanism underlying diabetes in cystic fibrosis (CF). Diabetes negatively impacts the clinical status of CF patients years before its onset. We aimed to evaluate if OGTT-derived indices of β-cell function are associated with early markers of lung disease. We carried out a cross-sectional study on 80 CF patients who performed OGTT, spirometry, and nitrogen-multiple breath washout test. β-cell glucose sensitivity and the insulinogenic indices were used as markers of β-cell function and first-phase insulin response to glucose stimulus. We used sex- and age-adjusted multiple linear regression models to estimate the association between OGTT-derived indices and lung function measures. An increment of β-cell glucose sensitivity equal to its interquartile range was associated with an increase in ppFEV1 of 7.6 points (95%CI: 0.8; 14.4) as well as with a decrease in LCI of -1.96 units (95%CI: -3.40; -0.51) and in Scond of -0.016 L-1 (95%CI: -0.026; -0.007). The corresponding figures for insulinogenic index were: 8.6 (95%CI: 3.4; 13.9) for ppFEV1 , -2.03 (95%CI: -3.13; -0.94) for LCI, and -0.014 L-1 (95%CI: -0.021; -0.071) for Scond . When adjusting also for 2-h plasma glucose, both β-cell glucose sensitivity and insulinogenic index remained inversely associated with Scond . Deterioration of β-cell function is related to early lung disease in young patients with mild to normal pulmonary function. This relationship is independent from hyperglycemia and mainly involves conductive airways.
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Affiliation(s)
- Carla Colombo
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy.,Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Cystic Fibrosis Centre, Milan, Italy
| | - Gianfranco Alicandro
- Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milano, Italy
| | - Simone Gambazza
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Cystic Fibrosis Centre, Milan, Italy.,Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milano, Italy.,Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, U.O.C. Direzione delle Professioni Sanitarie, Milan, Italy
| | - Palmiro Mileto
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Cystic Fibrosis Centre, Milan, Italy
| | - Andrea Mari
- Institute of Neuroscience, National Research Council, Padova, Italy
| | - Eleonora Grespan
- Institute of Neuroscience, National Research Council, Padova, Italy
| | - Erica Nazzari
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Cystic Fibrosis Centre, Milan, Italy
| | - Maria Chiara Russo
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Cystic Fibrosis Centre, Milan, Italy
| | - Alberto Battezzati
- Department of Food, Environmental and Nutritional Sciences, International Centre for the Assessment of Nutritional Status, University of Milan, Milan, Italy
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50
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Whitfield CA, Horsley A, Jensen OE. Modelling structural determinants of ventilation heterogeneity: A perturbative approach. PLoS One 2018; 13:e0208049. [PMID: 30496317 PMCID: PMC6264152 DOI: 10.1371/journal.pone.0208049] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 11/09/2018] [Indexed: 01/19/2023] Open
Abstract
We have developed a computational model of gas mixing and ventilation in the human lung represented as a bifurcating network. We have simulated multiple-breath washout (MBW), a clinical test for measuring ventilation heterogeneity (VH) in patients with obstructive lung conditions. By applying airway constrictions inter-regionally, we have predicted the response of MBW indices to obstructions and found that they detect a narrow range of severe constrictions that reduce airway radius to 10%–30% of healthy values. These results help to explain the success of the MBW test to distinguish obstructive lung conditions from healthy controls. Further, we have used a perturbative approach to account for intra-regional airway heterogeneity that avoids modelling each airway individually. We have found, for random airway heterogeneity, that the variance in MBW indices is greater when indices are already elevated due to constrictions. By quantifying this effect, we have shown that variability in lung structure and mechanical properties alone can lead to clinically significant variability in MBW indices (specifically the Lung Clearance Index—LCI, and the gradient of phase-III slopes—Scond), but only in cases simulating obstructive lung conditions. This method is a computationally efficient way to probe the lung’s sensitivity to structural changes, and to quantify uncertainty in predictions due to random variations in lung mechanical and structural properties.
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Affiliation(s)
- Carl A. Whitfield
- Division of Infection, Immunity and Respiratory Medicine, University of Manchester, Southmoor Road, Manchester, United Kingdom, M23 9LT
- School of Mathematics, University of Manchester, Oxford Road, Manchester, United Kingdom, M13 9PL
- * E-mail:
| | - Alex Horsley
- Division of Infection, Immunity and Respiratory Medicine, University of Manchester, Southmoor Road, Manchester, United Kingdom, M23 9LT
| | - Oliver E. Jensen
- School of Mathematics, University of Manchester, Oxford Road, Manchester, United Kingdom, M13 9PL
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