Managing cystic fibrosis: strategies that increase life expectancy and improve quality of life

Assessment of dietary intake in adults with cystic fibrosis pre and post commencement of Elexacaftor/Tezacaftor/Ivacaftor

BACKGROUND & AIMS

Elexacaftor, Tezacaftor, Ivacaftor has enhanced clinical outcomes, expected lifespan and quality of life for people with cystic fibrosis. Increased body mass index post- Elexacaftor, Tezacaftor, Ivacaftor is well documented, suggesting high-energy, high-fat recommendations may no longer be appropriate. This study aims to identify changes in dietary intake and nutritional parameters post gene modulator therapy Elexacaftor, Tezacaftor, Ivacaftor.

METHODS

A retrospective cohort study assessed diet and nutritional parameters of adults with cystic fibrosis (n = 40) pre- and post- Elexacaftor, Tezacaftor, Ivacaftor (9 ± 3 months). Dietary intake was analysed (24hr recalls), for total energy intake, macronutrient distribution, sodium, core food groups, and discretionary intakes being compared to Nutrition Guidelines for people with cystic fibrosis, and general population guidelines.

RESULTS

Total energy intake decreased from 139.3 to 116.6 kJ/kg/day (p = 0.012) and was below the estimated energy requirement for people with cystic fibrosis by 4457.3 kJ (p < 0.001), despite body mass index increasing (p=<0.001). Mean dietary sodium decreased from 3921.1 mg ± 1364.5 mg to 3517.1 mg ± 1251.7 mg (p = 0.028). Intake of protein was above, and total fat intake met the higher end of guidelines for people with cystic fibrosis. Saturated fat intake did not change (p = 0.403) however exceeded general guidelines of <10 % total energy intake in line with general population intake of 15.9 %. A decrease in discretionary foods (5.1-4.5 serves/d, p = 0.038) and increase in vegetable intake (interquartile range 1.0-2.9 to 1.5-3.7 serves/d, p = 0.036) was noted. Serum retinol levels increased from 1.7 μmol/L to 2.0 μmol/L (p = 0.003).

CONCLUSION

Dietary patterns of people with cystic fibrosis change following Elexacaftor, Tezacaftor, Ivacaftor commencement. While total energy intake decreased and vegetable intake increased, saturated fat and discretionary intake remained high, increasing risk of metabolic disease. An individualised approach is needed with modulator therapy and recognition that changing diet is a modifiable risk factor for chronic disease.

Advances in the restoration of CFTR in children and pwCF with "mild disease"

Cystic fibrosis (CF) is a progressive genetic disorder, with lung disease being the main cause of morbidity and mortality. While advances in treatment have extended life expectancy, lung function still declines over time. Early inflammation and chronic infection, particularly with pseudomonas, worsen outcomes. Current management focuses on nutrition, airway clearance and infection control, but CFTR modulators directly target the genetic defect, improving lung function and reducing pulmonary exacerbations. Early use of CFTR modulators can alter the course of the disease.

The ageing of people living with cystic fibrosis: what to expect now?

The prognosis of people with cystic fibrosis (pwCF) has improved dramatically with the introduction of cystic fibrosis transmembrane conductance regulator (CFTR) modulators (CFTRm). The ageing of the cystic fibrosis (CF) population is changing the disease landscape with the emergence of different needs and increasing comorbidities related to both age and long-term exposure to multiple treatments including CFTRm. Although the number of pwCF eligible for this treatment is expected to increase, major disparities in care and outcomes still exist in this population. Moreover, the long-term impact of the use of CFTRm is still partly unknown due to the current short follow-up and experience with their use, thus generating some uncertainties. The future spread and initiation of these drugs at an earlier stage of the disease is expected to reduce the systemic burden of systemic inflammation and its consequences on health. However, the prolonged life expectancy is accompanied by an increasing burden of age-related comorbidities, especially in the context of chronic disease. The clinical manifestations of the comorbidities directly or indirectly associated with CFTR dysfunction are changing, along with the disease dynamics and outcomes. Current protocols used to monitor slow disease progression will need continuous updates, including the composition of the multidisciplinary team for CF care, with a greater focus on the needs of the adult population.

Dietary intake and quality among adults with cystic fibrosis: A systematic review

AIMS

This systematic review aims to describe the dietary quality, dietary intake and related behaviours of adults diagnosed with cystic fibrosis.

METHODS

A comprehensive literature search was conducted in four databases (Medline, CINAHL, EMBASE, CENTRAL); studies were included if they addressed dietary intake, diet quality or eating behaviours among adults (≥15 years) living with cystic fibrosis and were published from January 2000 to November 2022. The Mixed Methods Appraisal Tool was used to assess the risk of bias and quality of included studies. Findings were synthesised narratively.

RESULTS

Nineteen observational studies (n = 2236) were included and considered high to moderate quality. Most (13/19) studies reported that individuals with cystic fibrosis were consuming high-energy diets; where studies reported energy intake as a proportion of requirements met, energy intake was high, even when using individualised or cystic fibrosis-specific referents. In addition, fat intakes as a proportion of energy appeared high (29%-39% of total energy), particularly as current guidelines recommend macronutrient profile similar to the general population (<30% of total energy). There was considerable variation in the reporting of fatty acid profiles and other nutrients. Five studies reported on concerns regarding diet and eating in this population.

CONCLUSION

Findings from the current review suggest dietary intakes of adults with cystic fibrosis appear to be less than optimal and concerns about diet, weight and food may be emerging in this population. Future research utilising consistent measures of dietary assessment and reporting, reporting of medical therapies, and exploring potential concerns about diet and eating is warranted.

Relationship between Pain, Physical Activity, Screen Time and Age among Young Children during the COVID-19 Pandemic

INTRODUCTION

During the COVID-19 pandemic, many countries implemented restrictions, social distancing measures, and lockdowns to limit the spread of the disease. These lockdowns have affected children's screen time (ST), pain, and physical activity (PA) levels. The present study aimed to explore the relationships between ST, pain, age, and PA before, during, and after the COVID-19 pandemic.

METHODS

The caregivers of 329 children (median age = 8 years) filled out an online self-reported survey about the children's PA, ST, and pain before, during, and after the COVID-19 curfew. Spearman's rank correlation coefficient was used to explore the associations between these variables.

RESULTS

After the curfew, pain that existed before the pandemic had a weak negative relationship with PA intensity (-0.11, p = 0.04) and a weak positive relationship with ST (r = +0.12, p = 0.04). There was a strong positive relationship between ST in all time periods (p > 0.01). PA and ST had a weak negative relationship (p > 0.05) during the curfew and after the curfew but not before the COVID-19 pandemic. Age had a weak positive correlation with ST in all time periods (p > 0.01). In addition, ST was affected by the curfew.

CONCLUSION

The study findings indicated that young children had longer ST during the curfew and after the curfew compared with before the curfew. Increasing PA could lessen children's ST, which could, in turn, increase the probability that their general pain would decrease.

Oral health and related outcomes in children and adolescents with cystic fibrosis: a scoping review

PURPOSE

Good oral health is important for children and adolescents with cystic fibrosis (CF). The purpose of this scoping review is to describe the existing evidence base regarding oral health in children and adolescents with CF and provide recommendations for future research.

METHODS

Using a scoping review framework, a comprehensive search was undertaken using medline, embase, and PubMed. The search strategy included broad terms relating to CF, oral health, and children and adolescents and included only papers written in English.

RESULTS

61 articles were included. Topics investigated included dental caries, enamel defects, periodontal health, dental staining, oral health related quality of life, dental management, and dental development of children and adolescents with CF.

CONCLUSION

Dental outcomes of children and adolescents with CF differ from the healthy population. The current literature describing dental health in children and adolescents with CF includes predominately descriptive analyses. A shift to hypothesis-based studies to explore causal relationships that explain the differences in dental outcomes seen in the CF population offers an opportunity to better understand the problems faced by children and adolescents with CF. Research that actively engages stakeholders, including children and adolescents with CF and their families will enable evidence-based recommendations to improve their oral health.

Maternal and fetal outcomes in multiparous women with Cystic Fibrosis

BACKGROUND

Quality of life and survival in Cystic Fibrosis (CF) have improved dramatically, making family planning a feasible option. Maternal and perinatal outcomes in women with CF (wwCF) are similar to those seen in the general population. However, the effect of undergoing multiple pregnancies is unknown.

METHODS

A multinational-multicenter retrospective cohort study. Data was obtained from 18 centers worldwide, anonymously, on wwCF 18-45 years old, including disease severity and outcome, as well as obstetric and newborn complications. Data were analyzed, within each individual patient to compare the outcomes of an initial pregnancy (1st or 2nd) with a multigravid pregnancy (≥3) as well as secondary analysis of grouped data to identify risk factors for disease progression or adverse neonatal outcomes. Three time periods were assessed - before, during, and after pregnancy.

RESULTS

The study population included 141 wwCF of whom 41 (29%) had ≥3 pregnancies, "multiparous". Data were collected on 246 pregnancies, between 1973 and 2020, 69 (28%) were multiparous. A greater decline in ppFEV1 was seen in multiparous women, primarily in pancreatic insufficient (PI) wwCF and those with two severe (class I-III) mutations. Multigravid pregnancies were shorter, especially in wwCF over 30 years old, who had high rates of prematurity and newborn complications. There was no effect on pulmonary exacerbations or disease-related complications.

CONCLUSIONS

Multiple pregnancies in wwCF are associated with accelerated respiratory deterioration and higher rates of preterm births. Therefore, strict follow-up by a multidisciplinary CF and obstetric team is needed in women who desire to carry multiple pregnancies.

PREFUL MRI for Monitoring Perfusion and Ventilation Changes after Elexacaftor-Tezacaftor-Ivacaftor Therapy for Cystic Fibrosis: A Feasibility Study

Purpose To assess the feasibility of monitoring the effects of elexacaftor-tezacaftor-ivacaftor (ETI) therapy on lung ventilation and perfusion in people with cystic fibrosis (CF), using phase-resolved functional lung (PREFUL) MRI. Materials and Methods This secondary analysis of a multicenter prospective study was carried out between August 2020 and March 2021 and included participants 12 years or older with CF who underwent PREFUL MRI, spirometry, sweat chloride test, and lung clearance index assessment before and 8-16 weeks after ETI therapy. For PREFUL-derived ventilation and perfusion parameter extraction, two-dimensional coronal dynamic gradient-echo MR images were evaluated with an automated quantitative pipeline. T1- and T2-weighted MR images and PREFUL perfusion maps were visually assessed for semiquantitative Eichinger scores. Wilcoxon signed rank test compared clinical parameters and PREFUL values before and after ETI therapy. Correlation of parameters was calculated as Spearman ρ correlation coefficient. Results Twenty-three participants (median age, 18 years [IQR: 14-24.5 years]; 13 female) were included. Quantitative PREFUL parameters, Eichinger score, and clinical parameters (lung clearance index = 21) showed significant improvement after ETI therapy. Ventilation defect percentage of regional ventilation decreased from 18% (IQR: 14%-25%) to 9% (IQR: 6%-17%) (P = .003) and perfusion defect percentage from 26% (IQR: 18%-36%) to 19% (IQR: 13%-24%) (P = .002). Areas of matching normal (healthy) ventilation and perfusion increased from 52% (IQR: 47%-68%) to 73% (IQR: 61%-83%). Visually assessed perfusion scores did not correlate with PREFUL perfusion (P = .11) nor with ventilation-perfusion match values (P = .38). Conclusion The study demonstrates the feasibility of PREFUL MRI for semiautomated quantitative assessment of perfusion and ventilation changes in response to ETI therapy in people with CF. Keywords: Pediatrics, MR-Functional Imaging, Pulmonary, Lung, Comparative Studies, Cystic Fibrosis, Elexacaftor-Tezacaftor-Ivacaftor Therapy, Fourier Decomposition, PREFUL, Free-Breathing Proton MRI, Pulmonary MRI, Perfusion, Functional MRI, CFTR, Modulator Therapy, Kaftrio Clinical trial registration no. NCT04732910 Supplemental material is available for this article. © RSNA, 2024.

Cystic fibrosis in Europe: improved lung function and longevity - reasons for cautious optimism, but challenges remain

BACKGROUND

Prognosis and disease severity in cystic fibrosis (CF) are linked to declining lung function. To characterise lung function by the number of adults in countries with different levels of Gross National Income (GNI), data from the European Cystic Fibrosis Society Patient Registry were utilised.

METHODS

Annual data including age, forced expiratory volume in 1 s (FEV1), anthropometry, genotype, respiratory cultures and CF-related diabetes (CFRD) were retrieved between 2011 and 2021. All countries were stratified into GNI per capita to reflect differences within Europe.

RESULTS

A consistent improvement in FEV1 % pred and survival was observed among the 47 621 people with CF (pwCF), including subjects with chronic Pseudomonas aeruginosa infection, CFRD and/or undernutrition. Mean values of FEV1 % pred changed from 85% to 94.2% for children and from 63.6% to 74.7% for adults. FEV1 % pred further increased among those carrying the F508del mutation in 2021, when elexacaftor/tezacaftor/ivacaftor was available. The number of adult pwCF increased from 13 312 in 2011 to 21 168 in 2021, showing a 60% increase. PwCF living in European lower income countries did not demonstrate a significant annual increase in FEV1 % pred or in the number of adults.

CONCLUSION

This pan-European analysis demonstrates a consistent improvement in FEV1 % pred, number of adult pwCF and survival over the last decade only in European higher and middle income countries. Urgent action is needed in the lower income countries where such improvement was not observed. The notable improvement observed in pwCF carrying the F508del mutation emphasises the need to develop treatments for all CF mutations.

ESPEN-ESPGHAN-ECFS guideline on nutrition care for cystic fibrosis

BACKGROUND

Nutritional status is paramount in Cystic Fibrosis (CF) and is directly correlated with morbidity and mortality. The first ESPEN-ESPGHAN-ECFS guidelines on nutrition care for infants, children, and adults with CF were published in 2016. An update to these guidelines is presented.

METHODS

The study was developed by an international multidisciplinary working group in accordance with officially accepted standards. Literature since 2016 was reviewed, PICO questions were discussed and the GRADE system was utilized. Statements were discussed and submitted for on-line voting by the Working Group and by all ESPEN members.

RESULTS

The Working Group updated the nutritional guidelines including assessment and management at all ages. Supplementation of vitamins and pancreatic enzymes remains largely the same. There are expanded chapters on pregnancy, CF-related liver disease, and CF-related diabetes, bone disease, nutritional and mineral supplements, and probiotics. There are new chapters on nutrition with highly effective modulator therapies and nutrition after organ transplantation.

Optimizing CFTR modulator therapy management for cystic fibrosis through the ReX platform

Background

Cystic fibrosis (CF) is a chronic multi-systemic disease that requires a complex daily treatment regimen. Therefore, there is sub-optimal adherence to CF therapies, and it was shown to impact its clinical and economic burden. Cystic fibrosis transmembrane conductance regulator modulators (CFTRm) are high-cost medications that demonstrated significant benefit in clinical trials. The aim of this study was to evaluate the safety, usability, and efficacy of the ReX platform in medication management of CFTRm for the treatment of people with CF (pwCF).

Methods

ReX is a patient engagement platform consisting of a cloud-based management system and a cell-enabled handheld device intended to dispense oral medication into the patient's mouth, following a pre-programmed treatment protocol. It provides real-time adherence data to caregivers and timely, personalized reminders to patients. This is a prospective multi-center open study for pwCFs older than 12 years, who had been prescribed CFTRm [elexacaftor/tezacaftor/ivacaftor (ETI) or tezacaftor/ivacaftor (TI)], and provided consent to use ReX platform to receive CFTRm and record their health condition. Study duration was 12-24 months, with clinic visits where physical examination, body mass index (BMI), and pulmonary function tests were performed, and user experience questionnaires were filled in.

Results

Ten pwCFs from two CF centers in Israel were included. The mean age was 31.5 years (range 15-74 years); eight were taking ETI and two TI. Median adherence to CFTRm was 97.5% (range 70%-100%) in the first year and 94% (range 84%-99%) in the second year, which is higher than the previously reported CFTRm adherence of ∼80%. No adverse events related to the use of the platform were reported. Patients reported ReX to be valuable to their treatment management and user friendly. Estimated mean forced expiratory volume in 1 s (FEV1%) increased from 74.4% to 80.8% (p = 0.004) over 2 years. Similarly, estimated BMI percentile increased from 53.5 to 59.0 (p < 0.001).

Conclusions

Using the ReX platform in medication management of pwCF treated by CFTRm is safe, easy to use, and effective in improving the adherence to treatment and the clinical outcomes. Consequently, this device may potentially reduce costs to healthcare providers. Further larger and long-term studies are required to examine the clinical benefits of the ReX platform.

The association between Attention-Deficit-Hyperactivity-Disorder (ADHD) symptoms and disease severity in people with Cystic Fibrosis (pwCF)

BACKGROUND

The hallmarks of Cystic fibrosis (CF), chronic infection and inflammation, require intensive daily treatment to maintain and improve quality of life and outcome. The incidence of Attention Deficit/Hyperactivity Disorder (ADHD) is increased in chronic inflammatory diseases. Previous studies suggested that the prevalence of ADHD in people with CF (pwCF) is higher than in the general population. The objective of this study was to evaluate the association between ADHD symptoms and parameters of CF disease severity, measured by demographic and clinical data.

METHODS

Based on our previous study, the results of ADHD questionnaires and the MOXOCPT (continuous performance task) from 143 pwCF (7-68 years old) were analyzed and linked to patient data such as forced expiratory volume in 1 second (FEV1)%predicted, body mass index (BMI), number of pulmonary exacerbations, days of antibiotic (Abx) treatment and serum inflammatory markers.

RESULTS

A positive correlation between FEV1 and ADHD questionnaire's score (p = 0.046) was observed in the children's group. Furthermore, BMI, white blood cells (WBC) count, and days of Abx treatment showed a positive correlation with some of the MOXOCPT parameters.

CONCLUSION

There is an association between ADHD symptoms and some parameters of CF disease severity. These results highlight the need for an early diagnosis of ADHD in pwCF, which have the potential to improve their ability to deal with the burden of their disease and consequently their quality of life. Additional research is needed to understand the full spectrum of ADHD pathophysiology and the relationship with chronic inflammatory diseases such as CF.

16S rRNA-Based Microbiota Profiling Assists Conventional Culture Analysis of Airway Samples from Pediatric Cystic Fibrosis Patients

16S-based sequencing provides broader information on the respiratory microbial community than conventional culturing. However, it (often) lacks species- and strain-level information. To overcome this issue, we used 16S rRNA-based sequencing results from 246 nasopharyngeal samples obtained from 20 infants with cystic fibrosis (CF) and 43 healthy infants, which were all 0 to 6 months old, and compared them to both standard (blind) diagnostic culturing and a 16S-sequencing-informed "targeted" reculturing approach. Using routine culturing, we almost uniquely detected Moraxella catarrhalis, Staphylococcus aureus, and Haemophilus influenzae (42%, 38%, and 33% of samples, respectively). Using the targeted reculturing approach, we were able to reculture 47% of the top-5 operational taxonomical units (OTUs) in the sequencing profiles. In total, we identified 60 species from 30 genera with a median of 3 species per sample (range, 1 to 8). We also identified up to 10 species per identified genus. The success of reculturing the top-5 genera present from the sequencing profile depended on the genus. In the case of Corynebacterium being in the top 5, we recultured them in 79% of samples, whereas for Staphylococcus, this value was only 25%. The success of reculturing was also correlated with the relative abundance of those genera in the corresponding sequencing profile. In conclusion, revisiting samples using 16S-based sequencing profiles to guide a targeted culturing approach led to the detection of more potential pathogens per sample than conventional culturing and may therefore be useful in the identification and, consequently, treatment of bacteria considered relevant for the deterioration or exacerbation of disease in patients like those with CF. IMPORTANCE Early and effective treatment of pulmonary infections in cystic fibrosis is vital to prevent chronic lung damage. Although microbial diagnostics and treatment decisions are still based on conventional culture methods, research is gradually focusing more on microbiome and metagenomic-based approaches. This study compared the results of both methods and proposed a way to combine the best of both worlds. Many species can relatively easily be recultured based on the 16S-based sequencing profile, and it provides more in-depth information about the microbial composition of a sample than that obtained through routine (blind) diagnostic culturing. Still, well-known pathogens can be missed by both routine diagnostic culture methods as well as by targeted reculture methods, sometimes even when they are highly abundant, which may be a consequence of either sample storage conditions or antibiotic treatment at the time of sampling.

Dry Powder Inhalation for Lung Delivery in Cystic Fibrosis

Pulmonary drug delivery has long been used for local and systemic administration of different medications used in acute and chronic respiratory diseases. Certain lung diseases, such as cystic fibrosis, rely heavily on chronic treatments, including targeted lung delivery. Pulmonary drug delivery possesses various physiological advantages compared to other delivery methods and is also convenient for the patient to use. However, the formulation of dry powder for pulmonary delivery proves challenging due to aerodynamic restrictions and the lower tolerance of the lung. The aim of this review is to provide an overview of the respiratory tract structure in patients with cystic fibrosis, including during acute and chronic lung infections and exacerbations. Furthermore, this review discusses the advantages of targeted lung delivery, including the physicochemical properties of dry powder and factors affecting clinical efficacy. Current inhalable drug treatments and drugs currently under development will also be discussed.

CFTR Modulators: Current Status and Evolving Knowledge

In the past decade, the medical management of people with cystic fibrosis (pwCF) has changed with the development of small molecules that partially restore the function of the defective CF transmembrane conductance regulator (CFTR) protein and are called CFTR modulators. Ivacaftor (IVA), a CFTR potentiator with a large effect on epithelial ion transport, was the first modulator approved in pwCF carrying gating mutations. Because IVA was unable to restore sufficient CFTR function in pwCF with other mutations, two CFTR correctors (lumacaftor and tezacaftor) were developed and used in combination with IVA in pwCF homozygous for F508del, the most common CFTR variant. However, LUM/IVA and TEZ/IVA were only moderately effective in F508del homozygous pwCF and had no efficacy in those with F508del and minimal function mutations. Elexacaftor, a second-generation corrector, was thus developed and combined to tezacaftor and ivacaftor (ELX/TEZ/IVA) to target pwCF with at least one F508del variant, corresponding to approximately 85% of pwCF. Both IVA and ELX/TEZ/IVA are considered highly effective modulator therapies (HEMTs) in eligible pwCF and are now approved for nearly 90% of the CF population over 6 years of age. HEMTs are responsible for rapid improvement in respiratory manifestations, including improvement in symptoms and lung function, and reduction in the rate of pulmonary exacerbations. The impact of HEMT on extrapulmonary manifestations of CF is less well established, although significant weight gain and improvement in quality of life have been demonstrated. Recent clinical trials and real-world studies suggest that benefits of HEMT could even prove greater when used earlier in life (i.e., in younger children and infants). This article shortly reviews the past 10 years of development and use of CFTR modulators. Effects of HEMT on extrapulmonary manifestations and on CF demographics are also discussed.

Organoid Technology and Its Role for Theratyping Applications in Cystic Fibrosis

Cystic fibrosis (CF) is a autosomal recessive, multisystemic disease caused by different mutations in the CFTR gene encoding CF transmembrane conductance regulator. Although symptom management is important to avoid complications, the approval of CFTR modulator drugs in the clinic has demonstrated significant improvements by targeting the primary molecular defect of CF and thereby preventing problems related to CFTR deficiency or dysfunction. CFTR modulator therapies have positively changed the patients' quality of life, especially for those who start their use at the onset of the disease. Due to early diagnosis with the implementation of newborn screening programs and considerable progress in the treatment options, nowadays pediatric mortality was dramatically reduced. In any case, the main obstacle to treat CF is to predict the drug response of patients due to genetic complexity and heterogeneity. Advances in 3D culture systems have led to the extrapolation of disease modeling and individual drug response in vitro by producing mini organs called "organoids" easily obtained from nasal and rectal mucosa biopsies. In this review, we focus primarily on patient-derived intestinal organoids used as in vitro model for CF disease. Organoids combine high-validity of outcomes with a high throughput, thus enabling CF disease classification, drug development and treatment optimization in a personalized manner.

Factors related to the readiness of Brazilian chronic pediatric patients to transition to care in adult clinics

OBJECTIVE

Advances in medicine have increased the life expectancy of pediatric patients with chronic illnesses, and challenges with the guided transition of adolescents and young adults from pediatric clinics to adult clinics have grown. The aim of this study was to better understand readiness and factors related to this transition process in Brazil.

METHOD

In this cross-sectional study of 308 patients aged from 16 to 21 years under follow-up in pediatric specialties, the degree of readiness for transition was assessed using the Transition Readiness Assessment Questionnaire (TRAQ) and its domains. Associations with demographic data, clinical data, socio-economic level, medication adherence, family functionality, and parental satisfaction with health care were evaluated.

RESULTS

The median TRAQ score was 3.7 (3.2 - 4.2). Better readiness was associated with female patients, socio-economic class A-B, current active employment, higher level of education, not failing any school year, attending medical appointments alone, functional family, and a good knowledge of disease and medications. A low correlation was observed between TRAQ and age. TRAQ presented good internal consistency (alpha-Cronbach 0.86). In the multiple linear regression, TRAQ score showed a significant association with female gender, advanced age, socio-economic class A-B, better knowledge of disease and medications, and independence to attend appointments alone.

CONCLUSION

TRAQ instrument can guide healthcare professionals to identify specific areas of approach, in order to support adolescents with chronic disease to set goals for their own personal development and improve their readiness to enter into the adult healthcare system. In this study, some factors were related to better TRAQ scores.

Ultrasound-guided placement of long peripheral cannula in children with cystic fibrosis

BACKGROUND

The natural history of cystic fibrosis (CF) lung disease is a chronic deterioration of lung function with intermittent episodes of pulmonary infectious exacerbations (PExs). Reliable venous access is a milestone of effective management of such exacerbations, managed both in hospital and outpatient chronic therapy. The aim of our study was to analyze the feasibility of ultrasound-guided positioning of long peripheral catheters (LPC) as reliable midterm venous access in children affected by CF.

METHODS

In this single-center prospective study, over a 60-month period, we included paediatric CF subjects admitted with PExs and undergoing intravenous antibiotic treatment. LPCs were inserted in all participants by paediatric anaesthesiologists with ultrasound guide technique. Prospective data were collected assessing catheter positioning procedure and complications.

RESULTS

A total of 122 LPC insertions were performed in 55 CF children. Participants had a median age of 6.75 years (interquatile range: 3.7-13.5) at the time of catheter insertion. Implantation was successful on the first attempt in 86% of cases; 2 (1%) major insertion-related complications were reported. Eighty-eight percent of catheters were electively removed at the end of antibiotic therapy without any complication. Seven percent of the catheters were removed electively for occlusion and 2% for local dislodgment.

CONCLUSIONS

The results of the present study suggest that ultrasound-guided positioning of LPCs are safe alternative means of peripheral venous access in children with chronic diseases such as CF.

Advances in Preclinical In Vitro Models for the Translation of Precision Medicine for Cystic Fibrosis

The development of preclinical in vitro models has provided significant progress to the studies of cystic fibrosis (CF), a frequently fatal monogenic disease caused by mutations in the gene encoding the CF transmembrane conductance regulator (CFTR) protein. Numerous cell lines were generated over the last 30 years and they have been instrumental not only in enhancing the understanding of CF pathological mechanisms but also in developing therapies targeting the underlying defects in CFTR mutations with further validation in patient-derived samples. Furthermore, recent advances toward precision medicine in CF have been made possible by optimizing protocols and establishing novel assays using human bronchial, nasal and rectal tissues, and by progressing from two-dimensional monocultures to more complex three-dimensional culture platforms. These models also enable to potentially predict clinical efficacy and responsiveness to CFTR modulator therapies at an individual level. In parallel, advanced systems, such as induced pluripotent stem cells and organ-on-a-chip, continue to be developed in order to more closely recapitulate human physiology for disease modeling and drug testing. In this review, we have highlighted novel and optimized cell models that are being used in CF research to develop novel CFTR-directed therapies (or alternative therapeutic interventions) and to expand the usage of existing modulator drugs to common and rare CF-causing mutations.

Body Mass Index Recovery after Lung Transplant for Cystic Fibrosis

Rationale: Many lung transplant recipients with cystic fibrosis (CF) have low preoperative body mass index (BMI); however, post-transplant BMI recovery is not well understood. Objectives: To evaluate BMI recovery (⩾18.5 kg/m2) among CF lung transplant recipients with low preoperative BMI and to investigate the association of survival with BMI recovery. Methods: The United Network for Organ Sharing and CF Foundation patient registries (June 2005-December 2016) were used to identify CF lung transplant recipients. Among recipients surviving ⩾1 year, Cox modeling compared post-transplant 1-year conditional survival between recipients with low (<17 and 17-18.49 kg/m2) versus normal preoperative BMI, stratified by BMI recovery. Results: Of 1,977 CF lung transplant recipients, 272 (14%) and 449 (23%) had a preoperative BMI of <17 and 17-18.49 kg/m2, respectively. For subgroups with a BMI of <17 and 17-18.49 kg/m2, 29% versus 49%, respectively, of those alive at 1 year recovered their BMI. Among recipients with low preoperative BMI, adjusted post-transplant 1-year conditional survival was worse than that in those with preoperative BMI ⩾ 18.5 kg/m2; however, BMI recovery mitigated this. Preoperative BMI < 17 kg/m2 had an adjusted hazard ratio of 1.29 (95% confidence interval [CI], 0.92-1.81) with BMI recovery versus 1.57 (95% CI, 1.09-2.25) without recovery, and preoperative BMI 17-18.49 kg/m2 had an adjusted hazard ratio of 1.28 (95% CI, 1.02-1.61) with BMI recovery versus 1.72 (95% CI, 1.14-2.59) without recovery. Conclusions: Patients with lower preoperative BMI were less likely to achieve BMI recovery within 1 year. However, for those who did, BMI recovery within 1 year after transplant was associated with longer survival.

Cystic fibrosis-related liver disease is an independent risk factor for mortality and increased health care resource utilization in hospitalized pediatric patients with cystic fibrosis

BACKGROUND

Cystic fibrosis-related liver disease (CFLD) is more prevalent in recent decades due to the increasing life expectancy of patients with cystic fibrosis (CF). There is paucity of population-level data on the impact of CFLD on hospital outcomes.

METHODS

We interrogated nonoverlapping years (2003-2016) of the National Inpatient Sample and Kids' Inpatient Database to include all hospitalized patients <21 years of age with a primary diagnosis of CF within the United States. A concomitant diagnosis of cirrhosis, liver fibrosis, chronic liver disease, portal hypertension, hepatomegaly, splenomegaly, hypersplenism, and liver transplant status was considered as surrogates for the diagnosis of CFLD and was compared with CF-related hospitalizations without these diagnoses (controls) for demographics, comorbid conditions, in-hospital mortality, length-of-stay, and hospital charges.

RESULTS

We evaluated 94,374 CF-related hospitalizations. The prevalence of CFLD was 5.8%. The prevalence increased from 3.1% (2003) to a peak of 7.3% (2014) with an overall increasing trend, p < 0.001. Hospitalizations with CFLD had an increased prevalence of significant comorbidities: respiratory failure,lung transplant, pulmonary hypertension, diabetes mellitus, malnutrition, Clostridioides difficile infection, cholelithiasis, anemia, and need for parenteral nutrition, p < 0.001. Multivariate regression models showed CFLD as independently associated with 2.1 (95% confidence interval [CI]: 1.5 to 2.8) times increased risk of inpatient mortality, contributed to 1.1 (95% CI: 0.89 to 1.37) additional days of hospitalization, and incurring $14,852 (95% CI: 12,204 to 17,501) excess hospital charges, p < 0.001.

CONCLUSION

CFLD is associated with multiple comorbidities and is independently associated with increased risk of mortality and increased health care resource utilization in pediatric CF-related hospitalizations.

CFTR Modulators in People with Cystic Fibrosis: Real-World Evidence in France

Cystic fibrosis (CF) is a rare genetic multisystemic disease, the manifestations of which are due to mutations in the gene encoding the CF transmembrane conductance regulator (CFTR) protein and can lead to respiratory insufficiency and premature death. CFTR modulators, which were developed in the past decade, partially restore CFTR protein function. Their clinical efficacy has been demonstrated in phase 3 clinical trials, particularly in terms of lung function and pulmonary exacerbations, nutritional status, and quality of life in people with gating mutations (ivacaftor), homozygous for the F508del mutation (lumacaftor/ivacaftor and tezacaftor/ivacaftor), and in those with at least one F508del mutation (elexacaftor/tezacaftor/ivacaftor). However, many questions remain regarding their long-term safety and effectiveness, particularly in patients with advanced lung disease, liver disease, renal insufficiency, or problematic bacterial colonization. The impact of CFTR modulators on other important outcomes such as concurrent treatments, lung transplantation, chest imaging, or pregnancies also warrants further investigation. The French CF Reference Network includes 47 CF centers that contribute patient data to the comprehensive French CF Registry and have conducted nationwide real-world studies on CFTR modulators. This review seeks to summarize the results of these real-world studies and examine their findings against those of randomized control trials.

The impact of FDA and EMA regulatory decision-making process on the access to CFTR modulators for the treatment of cystic fibrosis

Background

Over the past decade, a new class of drugs called CFTR (cystic fibrosis transmembrane conductance regulator) modulators have shown to be able to improve clinical outcomes in patient with Cystic Fibrosis. In this analysis, we have extensively reviewed the regulatory pathways and decisions adopted by FDA and EMA to speed up the development, the review and the approval of these drugs, with the aim of identifying possible clinical and public health implications associated with differences.

Results

CFTR modulators have been developed towards addressing three main genetic domains: (1) F508del homozygous (F508del/F508del), (2) F508del heterozygous, and (3) genotypes not carrying F508del mutation; and expanded from adult to paediatric population. Programs to expedite the reviewing and licensing of CFTR modulators were extensively adopted by FDA and EMA. All CFTR modulators have been licensed in the US as orphan drugs, but in the EU the orphan status for LUM/IVA was not confirmed at the time of marketing authorization as results from the pivotal trial were not considered clinically significant. While FDA and EMA approved CFTR modulators on the basis of results from phase III double-blind RCTs, main differences were found on the extension of indications: FDA accepted non-clinical evidence considering a recovery of the CFTR function ≥ 10% based on chloride transport, a reliable indicator to correlate with improvement in clinical outcomes. By contrast, EMA did not deem preclinical data sufficient to expand the label of CFTR modulators without confirmatory clinical data.

Conclusions

Regulators played an important role in fostering the development and approval of CFTR modulators. However, differences were found between FDA and EMA in the way of reviewing and licensing CFTR modulators, which extended beyond semantics affecting patients’ eligibility and access: FDA’s approach was more mechanistic/biology-driven while the EMA’s one was more oriented by clinical evidence. This might refer to the connection between the EMA and the Member States, which tends to base decisions on pricing and reimbursement on clinical data rather than pre-clinical ones. Here we have proposed a two-step personalized-based model to merge the ethical commitment of ensuring larger access to all potential eligible patients (including those harboring very rare mutations) with the one of ensuring access to clinically assessed and effective medicines through Real World Data.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-022-02350-5.

Bronchiectasis in Low-Dose CT Screening for Lung Cancer

Background Bronchiectasis is associated with loss of lung function, substantial use of health care resources, and increased morbidity and mortality in people with cardiopulmonary diseases. Purpose To assess the frequency and severity of bronchiectasis and related clinical findings of participants in a low-dose CT (LDCT) screening program. Materials and Methods The Early Lung and Cardiac Action Program (ELCAP) bronchiectasis score (range, 0-42; higher values indicate more severe bronchiectasis) was developed to facilitate bronchiectasis assessment. This quantitative scoring system screened participants based on accumulated knowledge and improved CT imaging capabilities. Secondary review of LDCT studies from smokers aged 40-90 years was performed when they were initially enrolled in the prospective Mount Sinai ELCAP screening study between 2010 and 2019. Medical records were reviewed to identify associated respiratory symptoms and acute respiratory events during the 2 years after LDCT. Logistic regression analysis was performed to examine factors associated with bronchiectasis. Results LDCT studies of 2191 screening participants (mean age, 65 years ± 9; 1140 [52%] women) were obtained, and bronchiectasis was identified in 504 (23%) participants. Median ELCAP bronchiectasis score was 12 (interquartile range, 9-16). Bronchiectasis was most common in the lower lobes for all participants, and lower lobe prevalence was greater with higher ELCAP score (eg, 91% prevalence with an ELCAP score of 16-42). In the fourth quartile, however, midlung involvement was higher compared with lower lung involvement (128 of 131 participants [98%] vs 122 of 131 participants [93%]). Bronchiectasis was more frequent with greater age (odds ratio [OR] = 2.0 per decade; 95% CI: 1.7, 2.4); being a former smoker (OR = 1.33; 95% CI: 1.01, 1.73); and having self-reported chronic obstructive pulmonary disease (OR = 1.38; 95% CI: 1.02, 1.88), an elevated hemidiaphragm (OR = 4; 95% CI: 2, 11), or consolidation (OR = 5; 95% CI: 3, 11). It was less frequent in overweight (OR = 0.7; 95% CI: 0.5, 0.9) or obese (OR = 0.6; 95% CI: 0.4, 0.8) participants. Two years after baseline LDCT, respiratory symptoms, acute respiratory events, and respiratory events that required hospitalization were more frequent with increasing severity of the ELCAP bronchiectasis score (P < .005 for all trends). Conclusion Prevalence of bronchiectasis in smokers undergoing low-dose CT screening was high, and respiratory symptoms and acute events were more frequent with increasing severity of the Early Lung and Cardiac Action Program Bronchiectasis score. © RSNA, 2022 See also the editorial by Verschakelen in this issue.

State-of-the-art review of lung imaging in cystic fibrosis with recommendations for pulmonologists and radiologists from the "iMAging managEment of cySTic fibROsis" (MAESTRO) consortium

OBJECTIVE

Imaging represents an important noninvasive means to assess cystic fibrosis (CF) lung disease, which remains the main cause of morbidity and mortality in CF patients. While the development of new imaging techniques has revolutionised clinical practice, advances have posed diagnostic and monitoring challenges. The authors aim to summarise these challenges and make evidence-based recommendations regarding imaging assessment for both clinicians and radiologists.

STUDY DESIGN

A committee of 21 experts in CF from the 10 largest specialist centres in Italy was convened, including a radiologist and a pulmonologist from each centre, with the overall aim of developing clear and actionable recommendations for lung imaging in CF. An a priori threshold of at least 80% of the votes was required for acceptance of each statement of recommendation.

RESULTS

After a systematic review of the relevant literature, the committee convened to evaluate 167 articles. Following five RAND conferences, consensus statements were developed by an executive subcommittee. The entire consensus committee voted and approved 28 main statements.

CONCLUSIONS

There is a need for international guidelines regarding the appropriate timing and selection of imaging modality for patients with CF lung disease; timing and selection depends upon the clinical scenario, the patient's age, lung function and type of treatment. Despite its ubiquity, the use of the chest radiograph remains controversial. Both computed tomography and magnetic resonance imaging should be routinely used to monitor CF lung disease. Future studies should focus on imaging protocol harmonisation both for computed tomography and for magnetic resonance imaging. The introduction of artificial intelligence imaging analysis may further revolutionise clinical practice by providing fast and reliable quantitative outcomes to assess disease status. To date, there is no evidence supporting the use of lung ultrasound to monitor CF lung disease.

Transition to adult care in cystic fibrosis: The challenges and the structure

In developed countries, it is projected that there will be a 70% increase in the number of adults living with Cystic Fibrosis (CF) between 2010 and 2025. This shift in demographics highlights the importance of high-quality transition programmes with developmentally appropriate integrated health care services as the individual moves through adolescence to adulthood. Adolescents living with CF face additional and unique challenges that may have long-term impacts on their health, quality of life and life-expectancy. CF specific issues around socially challenging symptoms, body image, reproductive health and treatment burden differentiate people with CF from their peers and require clinicians to identify and address these issues during the transition process. This review provides an overview of the health, developmental and psychosocial challenges faced by individuals with CF, their guardians and health care teams considering the fundamental components and tools that are required to build a transition programme that can be tailored to suit individual CF clinics.

Association of Body Mass Index With Clinical Outcomes in Patients With Cystic Fibrosis: A Systematic Review and Meta-analysis

IMPORTANCE

The prevalence of overweight (body mass index [BMI] = 25-29.9 [calculated as weight in kilograms divided by height in meters squared]) and obesity (BMI ≥30) is increasing among patients with cystic fibrosis (CF). However, it is unclear whether there is a benefit associated with increasing weight compared with the reference range (ie, normal) in CF.

OBJECTIVE

To evaluate the association of altered BMI or body composition and clinical outcomes in patients with CF.

DATA SOURCES

For this systematic review and meta-analysis, the literature search was conducted November 2, 2020, of 3 databases: MEDLINE (via PubMed), Embase, and Cochrane Central Register of Controlled Trials.

STUDY SELECTION

Patients older than 2 years diagnosed with CF with altered body composition or BMI were compared with patients having the measured parameters within the reference ranges. Records were selected by title, abstract, and full text; disagreements were resolved by consensus. Cohort studies and conference abstracts were eligible; articles with no original data and case reports were excluded.

DATA EXTRACTION AND SYNTHESIS

Two authors independently extracted data, which were validated by a third author. Studies containing insufficient poolable numerical data were included in the qualitative analysis. A random-effects model was applied in all analyses.

MAIN OUTCOMES AND MEASURES

Pulmonary function, exocrine pancreatic insufficiency (PI), and CF-related diabetes (CFRD) were investigated as primary outcomes. Odds ratios (ORs) or weighted mean differences (WMDs) with 95% CIs were calculated. The hypothesis was formulated before data collection.

RESULTS

Of 10 524 records identified, 61 met the selection criteria and were included in the qualitative analysis. Of these, 17 studies were included in the quantitative synthesis. Altogether, 9114 patients were included in the systematic review and meta-analysis. Overweight (WMD, -8.36%; 95% CI, -12.74% to -3.97%) and obesity (WMD, -12.06%; 95% CI, -23.91% to -0.22%) were associated with higher forced expiratory volume in the first second of expiration compared with normal weight. The odds for CFRD and PI were more likely in patients of normal weight (OR, 1.49; 95% CI, 1.10 to 2.00) than in those who were overweight (OR, 4.40; 95% CI, 3.00 to 6.45). High heterogeneity was shown in the analysis of pulmonary function (I2 = 46.7%-85.9%).

CONCLUSIONS AND RELEVANCE

The findings of this systematic review and meta-analysis suggest that the currently recommended target BMI in patients with CF should be reconsidered. Studies with long-term follow-up are necessary to assess the possible adverse effects of higher BMI or higher fat mass in patients with CF.

EVALUATING THE EFFICACY OF HUMAN BRONCHIECTASISBASED ANTIBIOTIC THERAPY IN THE TREATMENT OF ORANGUTAN RESPIRATORY DISEASE SYNDROME

Unique among apes, orangutans (Pongo spp.) develop a chronic respiratory disease called orangutan respiratory disease syndrome (ORDS). The authors define ORDS as intermittent bacterial infection and chronic inflammation of any region or combination of regions of the respiratory tract, including the sinuses, air sacs, cranial bones, airways, and lung parenchyma. Infection in any of these areas can present acutely but then becomes recurrent, chronic, progressive, and ultimately fatal. The closest model to this disease is cystic fibrosis (CF) in people. We hypothesized that use of a 4-8-wk course of combined oral antibiotics used in the treatment of bronchiectasis in CF patients would lead to prolonged symptomatic and computed tomography (CT) scan improvement in orangutans experiencing early signs of ORDS. Nine adult Bornean orangutans (Pongo pygmaeus, eight males, one female, 18-29 yr of age) diagnosed with early ORDS-like respiratory disease underwent CT scan before initiation of treatment. Each animal received a combined course of azithromycin (400 mg 3/wk, mean 7 mg/kg) and levofloxacin (500 mg PO q24h, mean 8.75 mg/kg) for a period of 4-8 wk. CT scan was repeated 6-14 mon after completion of antibiotic treatment. Pretreatment CT showed that six of nine animals had lower respiratory pathology (airway disease, pneumonia, or both). All six orangutans had concurrent sinusitis, mastoiditis, airsacculitis, or a combination of these conditions. Upper respiratory disease alone was observed in three animals. CT showed improvement or resolution in four of five sinusitis cases, improvement in one of two instances of mastoiditis, resolution in five of six instances of airsacculitis, improvement or resolution in six of six instance of lower airway disease (P = 0.03, 95% CI 0.54-1.0], and resolution in five of five cases of pneumonia. Resolution of pretreatment clinical signs was observed in all nine animals. Two developed signs not present at pretreatment. These results show that combination antibiotic therapy with azithromycin and levofloxacin provides improvement in clinical signs and CT evidence of ORDS-related pathology, resulting in symptom-free status in some animals for up to 33 mon.

Developing ciprofloxacin dry powder for inhalation: A story of challenges and rational design in the treatment of cystic fibrosis lung infection

Cystic fibrosis (CF) is an inherited multisystem disease affecting the lung which leads to a progressive decline in lung function as a result of malfunctioning mucociliary clearance and subsequent chronic bacterial infections. Pseudomonas aeruginosa is the predominant cause of lung infection in CF patients and is associated with significant morbidity and mortality. Thus, antibiotic therapy remains the cornerstone of the treatment of CF. Pulmonary delivery of antibiotics for lung infections significantly reduces the required dose and the associated systemic side effects while improving therapeutic outcomes. Ciprofloxacin is one of the most widely used antibiotics against P. aeruginosa and the most effective fluoroquinolone. However, in spite of the substantial amount of research aimed at developing ciprofloxacin powder for inhalation, none of these formulations has been commercialized. Here, we present an integrated view of the diverse challenges associated with delivering ciprofloxacin dry particles to the lungs of CF patients and the rationales behind recent formulations of ciprofloxacin dry powder for inhalation. This review will discuss the challenges in developing ciprofloxacin powder for inhalation along with the physiological and pathophysiological challenges such as ciprofloxacin lung permeability, overproduction of viscous mucus and bacterial biofilms. The review will also discuss the current and emerging particle engineering approaches to overcoming these challenges. By doing so, we believe the review will help the reader to understand the current limitations in developing an inhalable ciprofloxacin powder and explore new opportunities of rational design strategies.

Parent-Collected Oropharyngeal Swabs in Cystic Fibrosis

The validity of oropharyngeal swabs obtained by parents is described, and a case for parent-collection to be used as part of remote care is presented.

Anti-LPS IgA and IgG Can Inhibit Serum Killing of Pseudomonas aeruginosa in Patients with Cystic Fibrosis

Pseudomonas aeruginosa is one of the principal pathogens implicated in respiratory infections of patients with cystic fibrosis (CF) and non-CF bronchiectasis. Previously, we demonstrated that impaired serum-mediated killing of P. aeruginosa was associated with increased severity of respiratory infections in patients with non-CF bronchiectasis. This inhibition was mediated by high titers of O-antigen-specific IgG2 antibodies that cloak the surface of the bacteria, blocking access to the membrane. Infection-related symptomatology was ameliorated in patients by using plasmapheresis to remove the offending antibodies. To determine if these inhibitory "cloaking antibodies" were prevalent in patients with CF, we investigated 70 serum samples from patients with P. aeruginosa infection and 5 from those without P. aeruginosa infection. Of these patients, 32% had serum that inhibited the ability of healthy control serum to kill P. aeruginosa. Here, we demonstrate that this inhibition of killing requires O-antigen expression. Furthermore, we reveal that while IgG alone can inhibit the activity of healthy control serum, O-antigen-specific IgA in patient sera can also inhibit serum-killing. We found that antibody affinity, not just titer, was also important in the inhibition of serum-mediated killing. These studies provide novel insight into cloaking antibodies in human infection and may provide further options in CF and other diseases for treatment of recalcitrant P. aeruginosa infections.

Methods Used to Evaluate the Immediate Effects of Airway Clearance Techniques in Adults with Cystic Fibrosis: A Systematic Review and Meta-Analysis

This review reports on methods used to evaluate airway clearance techniques (ACT) in adults with CF and examined data for evidence of any effect. Sixty-eight studies described ACT in adequate detail and were included in this review. Frequently reported outcomes were sputum expectoration (72%) and spirometric lung function (60%). Compared with cough alone, following any ACT, there was a trend for greater sputum wet weight, however FEV₁ was not different. The mean (95% CI) within-group effect for sputum wet weight following any ACT was 12.43 g (9.28 to 15.58) (n = 30 studies) and for FEV₁ was 0.03 L (−0.17 to 0.24) (n = 14 studies). Meta-regression demonstrated that, when compared with cough alone, greater sputum wet weight was reported in groups that received additional ACT by between 2.45 and 3.94 g (F_3,66 = 2.97, p = 0.04). These data suggest the addition of ACT to cough alone may optimise sputum clearance; however, FEV₁ lacked sensitivity to detect this change. Importantly, this review highlights the lack of appropriate measures to assess ACT efficacy.

Recent advances in understanding ion transport mechanisms in polycystic kidney disease

This review focuses on the most recent advances in the understanding of the electrolyte transport-related mechanisms important for the development of severe inherited renal disorders, autosomal dominant (AD) and recessive (AR) forms of polycystic kidney disease (PKD). We provide here a basic overview of the origins and clinical aspects of ARPKD and ADPKD and discuss the implications of electrolyte transport in cystogenesis. Special attention is devoted to intracellular calcium handling by the cystic cells, with a focus on polycystins and fibrocystin, as well as other calcium level regulators, such as transient receptor potential vanilloid type 4 (TRPV4) channels, ciliary machinery, and purinergic receptor remodeling. Sodium transport is reviewed with a focus on the epithelial sodium channel (ENaC), and the role of chloride-dependent fluid secretion in cystic fluid accumulation is discussed. In addition, we highlight the emerging promising concepts in the field, such as potassium transport, and suggest some new avenues for research related to electrolyte handling.

Therapeutic pipeline for individuals with cystic fibrosis with mutations nonresponsive to current cystic fibrosis transmembrane conductance regulator modulators

PURPOSE OF REVIEW

Cystic fibrosis is a severe autosomal recessive disorder caused by mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR) encoding the CFTR protein, a chloride channel expressed in many epithelial cells. New drugs called CFTR modulators aim at restoring the CFTR protein function and they will benefit most of the patients with cystic fibrosis in the near future. However, more than 10% of CFTR mutations do not produce any CFTR protein for CFTR modulators to act upon, and the purpose of this review is to provide an overview of different approaches pursued to treat patients bearing mutations nonresponsive to CFTR modulators.

RECENT FINDINGS

These different approaches constitute readthrough agents for nonsense mutations, nucleic acid-based therapies, RNA-based or DNA-based, and cell-based therapies. Some approaches using mRNA or cDNA combined with a delivery vehicle are mutation-agnostic therapies. Other approaches, such as the use of tRNA, antisense oligonucleotides, gene editing or cell-based therapies are mutation-specific therapies.

SUMMARY

Most of these approaches are in preclinical development or for some of them, early clinical phases. Many hurdles and challenges will have to be solved before they can be safely translated to patients.

Therapeutic Approaches for Patients with Cystic Fibrosis Not Eligible for Current CFTR Modulators

Cystic fibrosis is a severe autosomal recessive disorder caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene encoding the CFTR protein, a chloride channel expressed in many epithelial cells. New drugs called CFTR modulators aim at restoring the CFTR protein function, and they will benefit many patients with cystic fibrosis in the near future. However, some patients bear rare mutations that are not yet eligible for CFTR modulators, although they might be amenable to these new disease-modifying drugs. Moreover, more than 10% of CFTR mutations do not produce any CFTR protein for CFTR modulators to act upon. The purpose of this review is to provide an overview of different approaches pursued to treat patients bearing mutations ineligible for CFTR modulators. One approach is to broaden the numbers of mutations eligible for CFTR modulators. This requires developing strategies to evaluate drugs in populations bearing very rare genotypes. Other approaches aiming at correcting the CFTR defect develop new mutation-specific or mutation-agnostic therapies for mutations that do not produce a CFTR protein: readthrough agents for nonsense mutations, nucleic acid-based therapies, RNA- or DNA-based, and cell-based therapies. Most of these approaches are in pre-clinical development or, for some of them, early clinical phases. Many hurdles and challenges will have to be solved before they can be safely translated to patients.

VX-809 mitigates disease in a mouse model of autosomal dominant polycystic kidney disease bearing the R3277C human mutation

Autosomal dominant polycystic kidney disease (ADPKD) is associated with the formation of renal cysts. We have devised a therapeutic approach, based on reversing the cyst phenotype from secretion to absorption by using VX-809, a modulator of the cystic fibrosis transmembrane regulator trafficking and processing. Our goal is to test VX-809 in RC/RC mice bearing the R3277C human mutation to demonstrate its therapeutic potential. We found that by 5 months of age, RC/RC mice had large cysts and impaired renal function, but when treated with VX-809 between the ages of 3 and 5 months, or 6 and 8 months, the cyst area was reduced in both groups, suggesting that VX-809 had shrunk previously existing cysts. After 2 months of treatment, the cyst size was lower than that of untreated animals of the same age. Our co-localization studies confirmed that cystic fibrosis transmembrane conductance regulator (CFTR) is found predominately at the apical membrane in the untreated animals of each age group, consistent with its role in Cl^- secretion; after VX-809 treatment, the basolateral membrane co-localization of CFTR increased ~4-fold, accompanied by a decrease of ~2-3-fold in its apical co-localization, indicating that VX-809 alters the phenotype to favor fluid absorption. Sodium/hydrogen exchanger and epithelial sodium channel, found in normal kidneys at the apical membrane, were almost absent from the cysts. VX-809 restored both levels toward normal. HSP27 is highly expressed in RC/RC mice and lowered toward normal by VX-809. Our demonstration of cyst reduction, improved renal function, and generation of an absorptive phenotype all strongly support the therapeutic potential of VX-809 as a treatment for ADPKD. We show here in an animal model of slowly progressing cyst formation typical of human ADPKD that VX-809 reduces the growth of already established cysts. The magnitude of the effect in the RC/RC mouse model when compared to previous experiments using the same mouse model to evaluate tolvaptan indicates that CFTR modulators warrant further development as a treatment for ADPKD.

The AWESCORE, a patient-reported outcome measure: development, feasibility, reliability, validity and responsiveness for adults with cystic fibrosis

Background

Quality of life has improved dramatically over the past two decades in people with cystic fibrosis (CF). Quantification has been enabled by patient-reported outcome measures (PROMs); however, many are lengthy and can be challenging to use in routine clinical practice. We propose a short-form PROM that correlates well with established quality-of-life measures.

Methods

We evaluated the utility of a 10-item score (AWESCORE) by measuring reliability, validity and responsiveness in adults with CF. The questions were developed by thematic analysis of survey questions to patients in a single adult CF centre. Each question was scored using a numerical rating scale 0 to 10. Total scores ranged from 0 to 100. Test-retest reliability was assessed over 24 h. To determine validity, comparisons were sought between stable subjects and those in pulmonary exacerbation, and between AWESCORE and Cystic Fibrosis Questionnaire - Revised (CFQ-R). Responsiveness to pulmonary exacerbation in individual subjects was evaluated.

Results

Five domains, each with two questions, were identified for respiratory, physical, nutritional, psychological and general health. A total of 246 consecutive adults attending the outpatient clinic completed the AWESCORE. Scores were higher during clinical stability compared to pulmonary exacerbation (mean± sd): 73±11 versus 48±11 (p<0.001). Each domain scored worse during an acute exacerbation (p<0.001). No differences in reliability were observed in scores on retesting using Bland-Altman comparison. The CFQ-R scores (mean±sd: 813±125) and AWESCORE (81±13) were moderately correlated (Pearson's r=0.649; p=0.002).

Conclusions

The AWESCORE is valid, reliable and responsive to altered health status in CF.

Leukodystrophies in Children: Diagnosis, Care, and Treatment

Leukodystrophies are a group of genetically determined disorders that affect development or maintenance of central nervous system myelin. Leukodystrophies have an incidence of at least 1 in 4700 live births and significant morbidity and elevated risk of early death. This report includes a discussion of the types of leukodystrophies; their prevalence, clinical presentation, symptoms, and diagnosis; and current and future treatments. Leukodystrophies can present at any age from infancy to adulthood, with variability in disease progression and clinical presentation, ranging from developmental delay to seizures to spasticity. Diagnosis is based on a combination of history, examination, and radiologic and laboratory findings, including genetic testing. Although there are few cures, there are significant opportunities for care and improvements in patient well-being. Rapid advances in imaging and diagnosis, the emergence of and requirement for timely treatments, and the addition of leukodystrophy screening to newborn screening, make an understanding of the leukodystrophies necessary for pediatricians and other care providers for children.

Assessing Shared Decision-Making in Cystic Fibrosis Care Using collaboRATE: A Cross-Sectional Study of 159 Programs

There are numerous opportunities for shared decision-making (SDM) in cystic fibrosis (CF) care, yet little is known about patients’ SDM experiences. This study evaluated SDM across 159 CF care programs (4024 participants) in the United States. Shared decision-making was assessed using the patient-reported collaboRATE measure, which was included in the CF Foundation’s Patient and Family Experience of Care Survey over 18 months. Overall, 69% of respondents reported experiencing SDM. Respondents at pediatric programs were more likely to experience SDM than those at adult programs (72% vs 67%, P < .001). Multivariable logistic regression analyses showed a relationship between SDM and patient age, whereby SDM was less likely to occur with patients aged 18 to 24 years, compared to some younger and older age groups (P = .02-<.001). Shared decision-making was more likely to occur at pediatric programs when patients had better general health (P = .02-<.01), and at pediatric and adult programs when patients had better mental health (P = .02-<.001). Disparities in SDM experiences highlight a need to improve decision-making processes in CF care. Interventions tailored for improving SDM among specific patient populations may be particularly advantageous.

Theratyping cystic fibrosis in vitro in ALI-culture and organoid models generated from patient-derived nasal epithelial Conditionally Reprogrammed Stem Cells

QUESTION

Cystic Fibrosis (CF) is due to pathogenic variants in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene. Recent improvement enabled pharmacologic therapy aiming at restoring mutated CFTR expression and function. CFTR "modulators" have revolutionised the CF therapeutic landscape, particularly the last approved Trikafta. This drug-combination is indicated by FDA and very recently by EMA for genotypes carrying at least one copy of CFTR with F508del pathogenic variant. However, several genotypes, are not eligible for Trikafta treatment, yet.

MATERIALS/PATIENTS AND METHODS

We exploited an innovative cellular approach allowing highly efficient in vitro-expansion of airway epithelial stem cells (AESC) through conditional reprogramming (CRC) from nasal brushing of CF patients. This approach, coupled to development of AESC-derived personalised disease models, as organoids and air liquid interface (ALI) cultures, revealed highly suitable for CFTR pharmacological-testing.

RESULTS AND ANSWER TO THE QUESTION

We fully validated the experimental models and implemented the CFTR functional assays and biochemical CFTR protein characterisation, that allowed to evaluate the efficacy of clinically available modulators in restoring CFTR maturation and function of each patient-derived "avatar" (theratyping). F508del homozygous genotypes, used as controls, confirmed the higher clinical activity of Trikafta in comparison with older modulators. Trikafta showed its efficacy also on three rare genotypes previously not eligible for modulators-treatment, opening the way to clinical translation. Finally, encouraging results for innovative drug combinations were also obtained.

Patterns of Health Insurance Coverage and Lung Disease Progression in Adolescents and Young Adults with Cystic Fibrosis

Rationale: Health insurance coverage has been implicated as a socioeconomic factor affecting clinical outcomes in patients with cystic fibrosis (CF), but evidence for this is mixed and varies by age.Objectives: Focusing on adolescents and young adults with CF, we examined how multiyear patterns of health insurance coverage were associated with lung function decline and related outcomes.Methods: We used data from the 2000 to 2015 CF Foundation Patient Registry to classify patients in three cohorts (ages 12-17 yr, adolescents; 18-23 yr, transitioning to adulthood; and 24-29 yr, young adults) according to health insurance coverage, as follows: continuous private, continuous public, intermittent public, and coverage gaps. The primary outcome was the percentage predicted forced expiratory volume in 1 second (FEV₁pp), which was modeled using mixed-effects regression. Additional outcomes included outpatient visits, hospital days for pulmonary exacerbation treatment, bacterial colonization, and body mass index. Outcomes were assessed over a 6-year period (e.g., ages 12-17 yr), whereas exposures were assessed over the prior 6 years (e.g., ages 6-11 yr).Results: The three cohorts included 3,365, 2,800, and 1,807 patients, respectively. The highest rate of FEV₁pp decline was found in the middle cohort, with the annual decline being steeper among patients with continuous public (-3.1/yr; 95% confidence interval [CI], -3.3 to -2.8) or intermittent public (-2.4/yr; 95% CI, -2.6 to -2.2) coverage compared with patients with continuous private coverage (-2.1/yr; 95% CI, -2.2 to -2.0). These differences were not explained by differences in outpatient care utilization.Conclusions: During the transition to adulthood, use of public insurance was associated with accelerated lung function decline among patients with CF. The role of insurance as a causal factor in this decline or proxy for other socioeconomic characteristics should be explored in further studies.

How abnormal is the normal? Clinical characteristics of CF patients with normal FEV1

BACKGROUND

Normal values (>80%) of Forced Expiratory Volume in one second (FEV₁ ) in patients with cystic fibrosis (CF) may lead to the interpretation that there is no lung disease. This study is a comprehensive analysis of lung involvement in CF patients having normal FEV₁ .

METHODS

Patients were recruited from two CF centers: Hadassah Medical Center, Jerusalem and Vall d' Hebron Hospital, Barcelona. Lung disease was assessed by lung clearance index (LCI), chest CT-Brody score, respiratory cultures, number of pulmonary exacerbations (PEx), and days of antibiotic treatment in the year before the assessment.

RESULTS

Of the 247 patients, 89 (36%) had FEV₁ ≥80% and were included in the study (mean age, 17.6; range, 4.25-49 years). Chronic Pseudomonas aeruginosa infection was found in 21%, and 31% had at least one major PEx in the year before the study. Abnormally elevated LCI was found in 86% of patients, ranging between 7.52 and 18.97, and total Brody score (TBS) was abnormal in 92% (range, 5.0-96.5). Patients with chronic P. aeruginosa had significantly higher LCI (p = .01) and TBS (p = .02) which were associated with more major PEx (p < .01 and p = .01, respectively) and more days of intravenous (IV) antibiotic treatment in the preceding year (p = .03 and p = .001, respectively).

CONCLUSIONS

Most CF patients with normal FEV₁ have already physiological and structural lung abnormalities which were associated with more PEx and IV antibiotic treatment. Further studies are needed to determine if better adherence to the currently used therapies and the new cystic fibrosis transmembrane modulators will prevent the progression of lung disease.

Cystic fibrosis in low and middle-income countries (LMIC): A view from four different regions of the world

Cystic fibrosis (CF) has been shown to affect people all over the world. While life expectancy for people with CF has increased substantially, CF is still associated with death in infants and young children in many regions, particularly in low and middle-income countries (LMIC). These countries face significant challenges to promote CF diagnosis and improvements to CF care due to financial constraints and a significant burden of other diseases. In this review, we describe the status of CF diagnosis and care in different LMIC settings, from four different parts of the world (Brazil, South Africa, Israel and India). We highlight challenges and opportunities for CF practitioners in LMIC to improve CF care and outcomes. While early CF diagnosis is the key to optimising outcomes, newborn screening may not be feasible for countries with lower CF incidence and higher birth rates, such as India or South Africa. CF therapies and care in LMIC need to be adapted to available resources of these countries. Collaboration initiatives of the global CF community with LMIC may improve CF care in these countries. Most individuals with CF in LMIC are not benefiting from CFTR modulator treatments due to the prohibitive cost of these drugs.