1
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Shah KS, Saiman L, LiPuma JJ, Kosorok MR, Muhlebach MS. Association of Pseudomonas aeruginosa incident infections with adherence to cystic fibrosis foundation care guidelines. J Cyst Fibros 2024; 23:300-305. [PMID: 37953182 DOI: 10.1016/j.jcf.2023.10.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 09/20/2023] [Accepted: 10/26/2023] [Indexed: 11/14/2023]
Abstract
BACKGROUND Care guidelines for cystic fibrosis (CF) have been developed to enhance consistent care and to improve health outcomes. We determined if adherence to CF care guidelines predicted P. aeruginosa incidence rates (Pa-IR) at U.S. CF centers in 2018. METHODS This cross-sectional CF Foundation Patient Registry study included 82 adult and 132 pediatric centers. Adherence to 12 guidelines was defined categorically (guideline met) or as a continuous measure (proportion of patients being treated/evaluated per guideline). Association of adherence to individual guidelines with Pa-IR, accounted for center and patient characteristics relevant to Pa-IR and were modeled using random forests and weighted-least-squares (WLS) analyses. RESULTS The mean Pa-IR was 0.2 cases/patient-years at risk (SE 0.0074) for all centers combined. Guideline adherence was lowest for ≥4 bacterial cultures/year (54% of centers) and annual oral glucose tolerance test (OGTT) (48% of centers), and highest for annual non-tuberculous mycobacteria (NTM) sputum culture (98%). The mean number of guidelines met was 6.7 and higher for pediatric (7.3) than adult (5.6) centers, (p<0.001). The number of guidelines met correlated negatively with Pa-IR (β=-0.007, p = 0.043). Macrolide prescription and annual OGTT per guideline were associated with lower and higher Pa-IR, respectively. Centers with lower center-wide lung function, higher proportion of pwCF with low body-mass index, and location in the Southwest had higher Pa-IR. CONCLUSION Overall adherence to guidelines was high except for performing ≥4 bacterial cultures/year and OGTT. Higher Pa-IR was associated with center characteristics and lower guideline adherence. The lower Pa-IR with greater adherence to guidelines suggests that focusing on quality care can positively impact Pa-IR.
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Affiliation(s)
- Kushal S Shah
- Department of Biostatistics, University of North Carolina, Chapel Hill, NC 27599, United States
| | - Lisa Saiman
- Department of Pediatrics, Columbia University Irving Medical Center, New York, NY 10032, United States
| | - John J LiPuma
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, MI 48104, United States
| | - Michael R Kosorok
- Department of Biostatistics, University of North Carolina, Chapel Hill, NC 27599, United States
| | - Marianne S Muhlebach
- Department of Pediatrics, University of North Carolina, Chapel Hill, NC 27599, United States; Marisco Lung Institute, University of North Carolina, Chapel Hill, NC 27599, United States.
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2
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Neff SL, Hampton TH, Koeppen K, Sarkar S, Latario CJ, Ross BD, Stanton BA. Rocket-miR, a translational launchpad for miRNA-based antimicrobial drug development. mSystems 2023; 8:e0065323. [PMID: 37975659 PMCID: PMC10734502 DOI: 10.1128/msystems.00653-23] [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: 06/22/2023] [Accepted: 10/06/2023] [Indexed: 11/19/2023] Open
Abstract
IMPORTANCE Antimicrobial-resistant infections contribute to millions of deaths worldwide every year. In particular, the group of bacteria collectively known as ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter sp.) pathogens are of considerable medical concern due to their virulence and exceptional ability to develop antibiotic resistance. New kinds of antimicrobial therapies are urgently needed to treat patients for whom existing antibiotics are ineffective. The Rocket-miR application predicts targets of human miRNAs in bacterial and fungal pathogens, rapidly identifying candidate miRNA-based antimicrobials. The application's target audience are microbiologists that have the laboratory resources to test the application's predictions. The Rocket-miR application currently supports 24 recognized human pathogens that are relevant to numerous diseases including cystic fibrosis, chronic obstructive pulmonary disease (COPD), urinary tract infections, and pneumonia. Furthermore, the application code was designed to be easily extendible to other human pathogens that commonly cause hospital-acquired infections.
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Affiliation(s)
- Samuel L. Neff
- Department of Microbiology and Immunology, Geisel School of Medicine, Dartmouth College, Hanover, New Hampshire, USA
| | - Thomas H. Hampton
- Department of Microbiology and Immunology, Geisel School of Medicine, Dartmouth College, Hanover, New Hampshire, USA
| | - Katja Koeppen
- Department of Microbiology and Immunology, Geisel School of Medicine, Dartmouth College, Hanover, New Hampshire, USA
| | - Sharanya Sarkar
- Department of Microbiology and Immunology, Geisel School of Medicine, Dartmouth College, Hanover, New Hampshire, USA
| | - Casey J. Latario
- Department of Microbiology and Immunology, Geisel School of Medicine, Dartmouth College, Hanover, New Hampshire, USA
| | - Benjamin D. Ross
- Department of Microbiology and Immunology, Geisel School of Medicine, Dartmouth College, Hanover, New Hampshire, USA
| | - Bruce A. Stanton
- Department of Microbiology and Immunology, Geisel School of Medicine, Dartmouth College, Hanover, New Hampshire, USA
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3
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Evaluating the alginate oligosaccharide (OligoG) as a therapy for Burkholderia cepacia complex cystic fibrosis lung infection. J Cyst Fibros 2022; 21:821-829. [DOI: 10.1016/j.jcf.2022.01.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 12/15/2021] [Accepted: 01/09/2022] [Indexed: 11/15/2022]
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4
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Sousa SA, Seixas AMM, Marques JMM, Leitão JH. Immunization and Immunotherapy Approaches against Pseudomonas aeruginosa and Burkholderia cepacia Complex Infections. Vaccines (Basel) 2021; 9:vaccines9060670. [PMID: 34207253 PMCID: PMC8234409 DOI: 10.3390/vaccines9060670] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/14/2021] [Accepted: 06/16/2021] [Indexed: 12/28/2022] Open
Abstract
Human infections caused by the opportunist pathogens Burkholderia cepacia complex and Pseudomonas aeruginosa are of particular concern due to their severity, their multiple antibiotic resistance, and the limited eradication efficiency of the current available treatments. New therapeutic options have been pursued, being vaccination strategies to prevent or limit these infections as a rational approach to tackle these infections. In this review, immunization and immunotherapy approaches currently available and under study against these bacterial pathogens is reviewed. Ongoing active and passive immunization clinical trials against P. aeruginosa infections is also reviewed. Novel identified bacterial targets and their possible exploitation for the development of immunization and immunotherapy strategies against P. aeruginosa and B. cepacia complex and infections are also presented and discussed.
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Affiliation(s)
- Sílvia A. Sousa
- Department of Bioengineering, IBB—Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal; (A.M.M.S.); (J.M.M.M.)
- Associate Laboratory, i4HB—Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
- Correspondence: (S.A.S.); (J.H.L.); Tel.: +351-218417688 (J.H.L.)
| | - António M. M. Seixas
- Department of Bioengineering, IBB—Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal; (A.M.M.S.); (J.M.M.M.)
- Associate Laboratory, i4HB—Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Joana M. M. Marques
- Department of Bioengineering, IBB—Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal; (A.M.M.S.); (J.M.M.M.)
| | - Jorge H. Leitão
- Department of Bioengineering, IBB—Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal; (A.M.M.S.); (J.M.M.M.)
- Associate Laboratory, i4HB—Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
- Correspondence: (S.A.S.); (J.H.L.); Tel.: +351-218417688 (J.H.L.)
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5
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Haggie S, Fitzgerald D. Pro con debates in clinical medicine infection prevention and control in cystic fibrosis: One size fits all? The argument in favour. Paediatr Respir Rev 2020; 36:97-99. [PMID: 32631758 PMCID: PMC7297174 DOI: 10.1016/j.prrv.2020.06.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 06/09/2020] [Indexed: 12/15/2022]
Abstract
This article advocates for a universal approach to infection control measures in cystic fibrosis. The central tenets of infection control include hand hygiene, contact precautions, regular microbiological surveillance and adopting inpatient, outpatient, domestic and social practices to minimise acquisition of common CF pathogens. Infection control measures should be proactive and prospective, assuming all patients harbour aggressive pathogens, and not relying on past culture results. The challenges of implementing these policies include cost, equipment, education, consistency, meticulousness all whilst balancing additional procedures to a busy clinical workload.
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Affiliation(s)
- S. Haggie
- Department of Respiratory Medicine, The Children’s Hospital at Westmead, Sydney, NSW, Australia,Discipline of Child & Adolescent Health, Sydney Medical School, Faculty of Health Sciences, University of Sydney, NSW, Australia,Corresponding author at: Department of Respiratory Medicine, The Children’s Hospital at Westmead, Sydney, NSW, Australia (S. Haggie)
| | - D.A. Fitzgerald
- Department of Respiratory Medicine, The Children’s Hospital at Westmead, Sydney, NSW, Australia,Discipline of Child & Adolescent Health, Sydney Medical School, Faculty of Health Sciences, University of Sydney, NSW, Australia
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6
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Tondro GH, Behzadpour N, Keykhaee Z, Akbari N, Sattarahmady N. Carbon@polypyrrole nanotubes as a photosensitizer in laser phototherapy of Pseudomonas aeruginosa. Colloids Surf B Biointerfaces 2019; 180:481-486. [PMID: 31102852 DOI: 10.1016/j.colsurfb.2019.05.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Revised: 05/05/2019] [Accepted: 05/09/2019] [Indexed: 02/06/2023]
Abstract
Phototherapy has been offered as an alternative and promising antibacterial strategy to overcome the antibiotic resistance problem. This study evaluated the antibacterial and phototherapy effects of carbon nanotubes with a polypyrrole coating in a core@shell structure (CNTs@PPy) on Pseudomonas aeruginosa (P. aeruginosa). P. aeruginosa was treated with CNTs@PPy at different concentrations (50-500 μg mL-1) in dark or laser light irradiation with a wavelength of 808 nm, a power density of 1000 mW cm-2 for 20 min. Temperature increment, cell viability, formation of reactive oxygen species (ROS) and protein/nucleic acid leakage subsequent the P. aeruginosa treatment were evaluated. The results showed that near-infrared laser irradiation of CNTs@PPy caused to a temperature increment confirming the ability of powerful photokilling of P. aeruginosa in a photothermal route. On the other hand, while CNTs@PPy represented just a 30-50% P. aeruginosa killing rate in dark, laser irradiation of 250 and 500 μg mL-1 concentrations of CNTs@PPy resulted in a ˜70% P. aeruginosa killing rate, along with significant ROS production into the medium and protein and nucleic acid leakage from P. aeruginosa. These later effects were assigned to a photodynamic route activity of CNTs@PPy upon laser irradiation. Therefore, CNTs@PPy acted as a photosensitizer in both photothermal and photodynamic therapies to present an enhanced bactericidal activity to annihilate and destroyed the gram-negative bacteria P. aeruginosa, a cause of many infectious diseases.
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Affiliation(s)
- G H Tondro
- Department of Medical Physics, School of Medicine, Nanomedicine and Nanobiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - N Behzadpour
- Department of Medical Physics, School of Medicine, Nanomedicine and Nanobiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Z Keykhaee
- Department of Medical Physics, School of Medicine, Nanomedicine and Nanobiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - N Akbari
- Department of Microbiology, Faculty of Science, Arak Branch, Islamic Azad University, Arak, Iran
| | - N Sattarahmady
- Department of Medical Physics, School of Medicine, Nanomedicine and Nanobiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
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7
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Rowbotham NJ, Palser SC, Smith SJ, Smyth AR. Infection prevention and control in cystic fibrosis: a systematic review of interventions. Expert Rev Respir Med 2019; 13:425-434. [DOI: 10.1080/17476348.2019.1595594] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Nicola J Rowbotham
- Evidence Based Child Health Group, Division of Child Health, Obstetrics & Gynaecology, Queens Medical Centre, Nottingham, UK
| | - Sally C Palser
- Evidence Based Child Health Group, Division of Child Health, Obstetrics & Gynaecology, Queens Medical Centre, Nottingham, UK
| | - Sherie J Smith
- Evidence Based Child Health Group, Division of Child Health, Obstetrics & Gynaecology, Queens Medical Centre, Nottingham, UK
| | - Alan R Smyth
- Evidence Based Child Health Group, Division of Child Health, Obstetrics & Gynaecology, Queens Medical Centre, Nottingham, UK
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8
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Semaniakou A, Croll RP, Chappe V. Animal Models in the Pathophysiology of Cystic Fibrosis. Front Pharmacol 2019; 9:1475. [PMID: 30662403 PMCID: PMC6328443 DOI: 10.3389/fphar.2018.01475] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 12/03/2018] [Indexed: 01/28/2023] Open
Abstract
Our understanding of the multiorgan pathology of cystic fibrosis (CF) has improved impressively during the last decades, but we still lack a full comprehension of the disease progression. Animal models have greatly contributed to the elucidation of specific mechanisms involved in CF pathophysiology and the development of new therapies. Soon after the cloning of the CF transmembrane conductance regulator (CFTR) gene in 1989, the first mouse model was generated and this model has dominated in vivo CF research ever since. Nonetheless, the failure of murine models to mirror human disease severity in the pancreas and lung has led to the generation of larger animal models such as pigs and ferrets. The following review presents and discusses data from the current animal models used in CF research.
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Affiliation(s)
- Anna Semaniakou
- Department of Physiology and Biophysics, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Roger P Croll
- Department of Physiology and Biophysics, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Valerie Chappe
- Department of Physiology and Biophysics, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
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9
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Andersen BM. Background Information: Isolation Routines. PREVENTION AND CONTROL OF INFECTIONS IN HOSPITALS 2019. [PMCID: PMC7122118 DOI: 10.1007/978-3-319-99921-0_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The isolation of patients with suspected or documented infections—to not spread to others—has been discussed for hundreds of years. Guidelines are many, methods are different, attitudes show vide variations, routines and procedures are still changing, regulations by law may be absent, and some healthcare professionals may be afraid of adverse outcomes of isolation [1–44]. Microbes that are spread in the environment, on the hands and equipment are invisible. The invisible agent does not call on attention before the infection; clinical disease, hospital infection or nosocomial infection is a factum that can be registered [23, 28, 29, 35–37]. How to stop the transmission is often “to believe and not believe” in infection control.
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10
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Postgenomic Approaches and Bioinformatics Tools to Advance the Development of Vaccines against Bacteria of the Burkholderia cepacia Complex. Vaccines (Basel) 2018; 6:vaccines6020034. [PMID: 29890657 PMCID: PMC6027386 DOI: 10.3390/vaccines6020034] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 06/05/2018] [Accepted: 06/06/2018] [Indexed: 12/19/2022] Open
Abstract
Bacteria of the Burkholderia cepacia complex (Bcc) remain an important cause of morbidity and mortality among patients suffering from cystic fibrosis. Eradication of these pathogens by antimicrobial therapy often fails, highlighting the need to develop novel strategies to eradicate infections. Vaccines are attractive since they can confer protection to particularly vulnerable patients, as is the case of cystic fibrosis patients. Several studies have identified specific virulence factors and proteins as potential subunit vaccine candidates. So far, no vaccine is available to protect from Bcc infections. In the present work, we review the most promising postgenomic approaches and selected web tools available to speed up the identification of immunogenic proteins with the potential of conferring protection against Bcc infections.
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11
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Saiman L, Siegel JD, LiPuma JJ, Brown RF, Bryson EA, Chambers MJ, Downer VS, Fliege J, Hazle LA, Jain M, Marshall BC, O’Malley C, Pattee SR, Potter-Bynoe G, Reid S, Robinson KA, Sabadosa KA, Schmidt HJ, Tullis E, Webber J, Weber DJ. Infection Prevention and Control Guideline for Cystic Fibrosis: 2013 Update. Infect Control Hosp Epidemiol 2016; 35 Suppl 1:S1-S67. [DOI: 10.1086/676882] [Citation(s) in RCA: 270] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The 2013 Infection Prevention and Control (IP&C) Guideline for Cystic Fibrosis (CF) was commissioned by the CF Foundation as an update of the 2003 Infection Control Guideline for CF. During the past decade, new knowledge and new challenges provided the following rationale to develop updated IP&C strategies for this unique population:1.The need to integrate relevant recommendations from evidence-based guidelines published since 2003 into IP&C practices for CF. These included guidelines from the Centers for Disease Control and Prevention (CDC)/Healthcare Infection Control Practices Advisory Committee (HICPAC), the World Health Organization (WHO), and key professional societies, including the Infectious Diseases Society of America (IDSA) and the Society for Healthcare Epidemiology of America (SHEA). During the past decade, new evidence has led to a renewed emphasis on source containment of potential pathogens and the role played by the contaminated healthcare environment in the transmission of infectious agents. Furthermore, an increased understanding of the importance of the application of implementation science, monitoring adherence, and feedback principles has been shown to increase the effectiveness of IP&C guideline recommendations.2.Experience with emerging pathogens in the non-CF population has expanded our understanding of droplet transmission of respiratory pathogens and can inform IP&C strategies for CF. These pathogens include severe acute respiratory syndrome coronavirus and the 2009 influenza A H1N1. Lessons learned about preventing transmission of methicillin-resistantStaphylococcus aureus(MRSA) and multidrug-resistant gram-negative pathogens in non-CF patient populations also can inform IP&C strategies for CF.
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12
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Khan MS, Bhaisare ML, Gopal J, Wu HF. Highly efficient gold nanorods assisted laser phototherapy for rapid treatment on mice wound infected by pathogenic bacteria. J IND ENG CHEM 2016. [DOI: 10.1016/j.jiec.2015.12.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Savant AP, O'Malley C, Bichl S, McColley SA. Improved patient safety through reduced airway infection rates in a paediatric cystic fibrosis programme after a quality improvement effort to enhance infection prevention and control measures. BMJ Qual Saf 2015; 23 Suppl 1:i73-i80. [PMID: 24608553 DOI: 10.1136/bmjqs-2013-002315] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
OBJECTIVE To reduce the risk of pathogen transmission between patients with cystic fibrosis (CF) and decrease the rate of acquisition of new CF pathogens in our patients. DESIGN Using the Model for Improvement, we developed a new process for infection prevention and control in our outpatient CF clinics. SETTING Paediatric CF programme at Ann & Robert H. Lurie Children's Hospital of Chicago; approximately 180 paediatric patients aged birth to 21 years. PARTICIPANTS All paediatric patients enrolled in the Cystic Fibrosis Foundation Patient Data Registry at this institution. INTERVENTIONS Implemented contact precautions with all patients, regardless of respiratory tract culture results. MEASUREMENT Respiratory tract culture rates of specific pathogens by quarter were compared prior to and after implementation. RESULTS Our percentage of patients with a positive respiratory tract culture for Pseudomonas aeruginosa dropped from 30% to 21% (p<0.0001) and for methicillin-resistant Staphylococcus aureus (MRSA) dropped from 10.8% to 8.7% (p=0.008). CONCLUSIONS Use of contact precautions by all care providers, for all patients, regardless of respiratory tract culture results resulted in decreased P aeruginosa and MRSA infection rates.
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Affiliation(s)
- Adrienne P Savant
- Division of Pulmonary Medicine, Department of Pediatrics, Ann & Robert H. Lurie Children's Hospital of Chicago, , Chicago, Illinois, USA
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Lynch KH, Dennis JJ. Cangene Gold Medal Award Lecture — Genomic analysis and modification ofBurkholderia cepaciacomplex bacteriophages1This article is based on a presentation by Dr. Karlene Lynch at the 61st Annual Meeting of the Canadian Society of Microbiologists in St. John’s, Newfoundland and Labrador, on 21 June 2011. Dr. Lynch was the recipient of the 2011 Cangene Gold Medal as the Canadian Graduate Student Microbiologist of the Year, an annual award sponsored by Cangene Corporation intended to recognize excellence in graduate research. Can J Microbiol 2012; 58:221-35. [DOI: 10.1139/w11-135] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The Burkholderia cepacia complex (Bcc) is a group of 17 Gram-negative predominantly environmental bacterial species that cause potentially fatal opportunistic infections in cystic fibrosis (CF) patients. Although its prevalence in these individuals is lower than that of Staphylococcus aureus and Pseudomonas aeruginosa , the Bcc remains a serious problem in the CF community because of the pathogenicity, transmissibility, and inherent antibiotic resistance of these organisms. An alternative treatment for Bcc infections that is currently being developed is phage therapy, the clinical use of viruses that infect bacteria. To assess the suitability of individual phage isolates for therapeutic use, the complete genome sequences of a panel of Bcc‐specific phages were determined and analyzed. These sequences encode a broad range of proteins with a gradient of relatedness to phage and bacterial gene products from Burkholderia and other genera. The majority of these phages were found not to encode virulence factors, and despite their predominantly temperate nature, a proof-of-principle experiment has shown that they may be modified to a lytic form. Both the genomic characterization and subsequent engineering of Bcc‐specific phages are fundamental to the development of an effective phage therapy strategy for these bacteria.
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Affiliation(s)
- Karlene H. Lynch
- 6-008 Centennial Centre for Interdisciplinary Science, Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Jonathan J. Dennis
- 6-008 Centennial Centre for Interdisciplinary Science, Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
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15
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Australian epidemic strain pseudomonas (AES-1) declines further in a cohort segregated cystic fibrosis clinic. J Cyst Fibros 2012; 11:49-52. [DOI: 10.1016/j.jcf.2011.08.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Revised: 08/13/2011] [Accepted: 08/14/2011] [Indexed: 11/21/2022]
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Masterson TL, Wildman BG, Newberry BH, Omlor GJ. Impact of age and gender on adherence to infection control guidelines and medical regimens in cystic fibrosis. Pediatr Pulmonol 2011; 46:295-301. [PMID: 20967838 DOI: 10.1002/ppul.21366] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Revised: 07/20/2010] [Accepted: 07/20/2010] [Indexed: 11/06/2022]
Abstract
RATIONALE The goal of the present research was to examine the impact of age and gender on adherence to both infection control (IC) guidelines and traditional medical treatments in a cystic fibrosis (CF) population. Adherence behaviors are consistently suboptimal in chronic illness populations, particularly pulmonary diseases; understanding the factors related to adherence behaviors in CF can aid in the development of interventions to promote adherence. METHOD Participants consisted of 74 individuals with CF ages 9 years and above. Participants were asked to complete questionnaires designed to assess demographic data, treatment adherence, and health beliefs. RESULTS With respect to IC guidelines, chi-square analyses revealed significant age differences in adherence behaviors such that the young adult subsample was least adherent to IC (χ2 = 15.10, df = 6, P = 0.020). Next, a 4 (age: child, adolescent, young adult, adult) × 2 (gender) completely between subjects analysis of variance (ANOVA) was conducted on medical treatment adherence. There was a significant main effect for age [F(3, 65) = 2.940, P = 0.040, ηP2 = 0.119] indicating that the adolescent subsample had the most adherence challenges. Gender was nonsignificant across both adherence types. CONCLUSIONS Study findings are suggestive of age-related differences in adherence behaviors across both IC and medical regimens and support the use of developmentally sensitive approaches to assessment and interventions addressing adherence.
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17
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Hauser AR, Jain M, Bar-Meir M, McColley SA. Clinical significance of microbial infection and adaptation in cystic fibrosis. Clin Microbiol Rev 2011; 24:29-70. [PMID: 21233507 PMCID: PMC3021203 DOI: 10.1128/cmr.00036-10] [Citation(s) in RCA: 284] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
A select group of microorganisms inhabit the airways of individuals with cystic fibrosis. Once established within the pulmonary environment in these patients, many of these microbes adapt by altering aspects of their structure and physiology. Some of these microbes and adaptations are associated with more rapid deterioration in lung function and overall clinical status, whereas others appear to have little effect. Here we review current evidence supporting or refuting a role for the different microbes and their adaptations in contributing to poor clinical outcomes in cystic fibrosis.
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Affiliation(s)
- Alan R Hauser
- Department of Microbiology/Immunology, Northwestern University, 303 E. Chicago Ave., Searle 6-495, Chicago, IL 60611, USA.
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Tierney S, Riley D, Jones AM, Webb AK, Horne M. Sputum issues as defined by patients with cystic fibrosis: a qualitative investigation. Chronic Illn 2010; 6:192-201. [PMID: 20634227 DOI: 10.1177/1742395310372812] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVES Patients with cystic fibrosis (CF) are asked to provide a sputum sample at clinic to test for potentially harmful pathogens. However, some appear to struggle with this request. Research into the difficulties experienced by these patients is lacking. This study set out to explore this issue in depth, using a qualitative research approach. METHODS Semi-structured interviews were conducted with 18 patients identified as having difficulties with sputum by the physiotherapists involved in their care. Framework analysis was applied to collected data. RESULTS An overarching concept derived from the interview material was a concern about sputum coming to be a defining feature of identity. This was reflected in the following four themes: (1) being seen as dirty because sputum is socially vilified as thus; (2) sputum exposing an invisible condition; (3) sputum acting as a reminder of having CF; (4) being seen as sputum producers by practitioners. DISCUSSION Patients' difficulties with expectorating sputum were multifaceted and included psychosocial and physical factors. Practitioners need to appreciate that for some people, a request for sputum can cause significant discomfort. Individualized interventions to assist these patients may prove helpful.
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Affiliation(s)
- S Tierney
- School of Nursing, Midwifery and Social Work, University of Manchester, University Place, Oxford Road, Manchester M13 9PL, UK.
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19
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Burkholderia cepacia Complex: Emerging Multihost Pathogens Equipped with a Wide Range of Virulence Factors and Determinants. Int J Microbiol 2010; 2011. [PMID: 20811541 PMCID: PMC2929507 DOI: 10.1155/2011/607575] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2010] [Accepted: 06/02/2010] [Indexed: 12/04/2022] Open
Abstract
The Burkholderia cepacia complex (Bcc) comprises at least 17 closely-related species of the β-proteobacteria subdivision, widely distributed in natural and man-made inhabitats. Bcc bacteria are endowed with an extraordinary metabolic diversity and emerged in the 1980s as life-threatening and difficult-to-treat pathogens among patients suffering from cystic fibrosis. More recently, these bacteria became recognized as a threat to hospitalized patients suffering from other diseases, in particular oncological patients. In the present paper, we review these and other traits of Bcc bacteria, as well as some of the strategies used to identify and validate the virulence factors and determinants used by these bacteria. The identification and characterization of these virulence factors is expected to lead to the design of novel therapeutic strategies to fight the infections caused by these emergent multidrug resistant human pathogens.
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20
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Fallon JP, Reeves EP, Kavanagh K. Inhibition of neutrophil function following exposure to the Aspergillus fumigatus toxin fumagillin. J Med Microbiol 2010; 59:625-633. [PMID: 20203215 DOI: 10.1099/jmm.0.018192-0] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The filamentous fungus Aspergillus fumigatus produces a variety of enzymes and toxins that may facilitate fungal colonization of tissue and evasion of the host immune response. One such toxin, fumagillin, was investigated for its ability to inhibit the action of neutrophils, which are a central component of the innate immune response to microbial infection. Neutrophils exposed to 2 microg fumagillin ml(-1) for 25 min showed a significantly reduced ability to kill yeast cells (P<0.02), to phagocytose conidia of A. fumigatus (P<0.023) and to consume oxygen (P<0.032). The ability of neutrophils to generate superoxide is dependent upon the action of a functional NADPH oxidase complex which is composed of cytosolic (p40phox, p47phox, p67phox, Rac2) and membrane (gp91phox) proteins. Exposure of neutrophils to fumagillin inhibited the formation of the NADPH oxidase complex by blocking the translocation of p47phox from the cytosolic to the membrane fraction (P=0.02). In addition to the production of superoxide, neutrophils also undergo degranulation, which leads to the release of proteolytic enzymes that contribute to the microbicidal activity of the cell. Fumagillin-treated neutrophils showed reduced degranulation as evidenced by lower myeloperoxidase activity (P<0.019). Fumagillin-treated cells demonstrated reduced levels of F-actin, thus indicating that retarding the formation of F-actin may contribute to the inhibition of the structural rearrangements required in the activated neutrophil. This work indicates that fumagillin may contribute to reducing the local immune response by altering the activity of neutrophils and thus facilitate the continued persistence and growth of A. fumigatus in the host.
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Affiliation(s)
- John P Fallon
- Medical Mycology Unit, Department of Biology, National Institute for Cellular Biotechnology, National University of Ireland Maynooth, Co. Kildare, Ireland
| | - Emer P Reeves
- Respiratory Research Division, Department of Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland
| | - Kevin Kavanagh
- Medical Mycology Unit, Department of Biology, National Institute for Cellular Biotechnology, National University of Ireland Maynooth, Co. Kildare, Ireland
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Abstract
Chronic infection with the environmental bacterium Pseudomonas aeruginosa is associated with greater morbidity and mortality for people with cystic fibrosis. Strict infection control measures including segregation appear to reduce but not eliminate the risk of initial acquisition of the organism. There is now good evidence from randomized controlled trials that early eradication regimens consisting of anti-pseudomonal antibiotics are effective in clearing P. aeruginosa and delaying the development of chronic infection in the majority of subjects. These regimens are safe and cost-effective. Ensuring that such regimens are widely adopted is therefore of considerable importance to improving outcomes for people with cystic fibrosis. The most effective antibiotic regimen, and the effects of new nebulizer technologies and methods to improve concordance remain to be determined.
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Affiliation(s)
- T W R Lee
- Leeds Regional Paediatric Cystic Fibrosis Centre, Childrens' Day Hospital, St James's University Hospital, Leeds, UK.
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22
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Davies JC, Alton EW. Monitoring respiratory disease severity in cystic fibrosis. Respir Care 2009; 54:606-17. [PMID: 19393105 DOI: 10.4187/aarc0493] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Measurements of disease severity provide a guide for the physician to tailor therapies, for the patient and family to gauge progress, and are required for clinical trials. For many respiratory diseases, including cystic fibrosis, sensitive, noninvasive measurements are few, and some of those that are available are applicable only to certain subgroups of patients or lack sufficient sensitivity. We discuss currently available measurements in 4 groups: physiology, infection, inflammation, and radiology. For each group we highlight strengths and weaknesses, ask how we could improve upon these, and provide details of alternative methods.
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Affiliation(s)
- Jane C Davies
- Department of Gene Therapy, Imperial College, Emmanuel Kaye Building, Manresa Road, London SW3 6NP, United Kingdom.
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23
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McClean S, Callaghan M. Burkholderia cepacia complex: epithelial cell–pathogen confrontations and potential for therapeutic intervention. J Med Microbiol 2009; 58:1-12. [DOI: 10.1099/jmm.0.47788-0] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Burkholderia cepaciacomplex (Bcc) is an important and virulent pathogen in cystic fibrosis patients. The interactions between this pathogen and the host lung epithelium are being widely investigated but remain to be elucidated. The complex is very versatile and its interactions with the lung epithelial cells are many and varied. The first steps in the interaction are penetration of the mucosal blanket and subsequent adherence to the epithelial cell surface. A range of epithelial receptors have been reported to bind to Bcc. The next step in pathogenesis is the invasion of the lung epithelial cell and also translocation across the epithelium to the serosal side. Furthermore, pathogenesis is mediated by a range of virulence factors that elicit their effects on the epithelial cells. This review outlines these interactions and examines the therapeutic implications of understanding the mechanisms of pathogenesis of this difficult, antibiotic-resistant, opportunistic pathogen.
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Affiliation(s)
- Siobhán McClean
- Centre of Microbial Host Interactions, Institute of Technology Tallaght Dublin, Dublin 24, Ireland
| | - Máire Callaghan
- Centre of Microbial Host Interactions, Institute of Technology Tallaght Dublin, Dublin 24, Ireland
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24
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Kukavica-Ibrulj I, Levesque RC. Animal models of chronic lung infection with Pseudomonas aeruginosa: useful tools for cystic fibrosis studies. Lab Anim 2008; 42:389-412. [PMID: 18782827 DOI: 10.1258/la.2007.06014e] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Cystic fibrosis (CF) is caused by a defect in the transmembrane conductance regulator (CFTR) protein that functions as a chloride channel. Dysfunction of the CFTR protein results in salty sweat, pancreatic insufficiency, intestinal obstruction, male infertility and severe pulmonary disease. In most patients with CF life expectancy is limited due to a progressive loss of functional lung tissue. Early in life a persistent neutrophylic inflammation can be demonstrated in the airways. The cause of this inflammation, the role of CFTR and the cause of lung morbidity by different CF-specific bacteria, mostly Pseudomonas aeruginosa, are not well understood. The lack of an appropriate animal model with multi-organ pathology having the characteristics of the human form of CF has hampered our understanding of the pathobiology and chronic lung infections of the disease for many years. This review summarizes the main characteristics of CF and focuses on several available animal models that have been frequently used in CF research. A better understanding of the chronic lung infection caused particularly by P. aeruginosa, the pathophysiology of lung inflammation and the pathogenesis of lung disease necessitates animal models to understand CF, and to develop and improve treatment.
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Affiliation(s)
- I Kukavica-Ibrulj
- Centre de Recherche sur la Fonction, Structure et Ingénierie des Protéines, Pavillon Charles-Eugène Marchand, Biologie Médicale, Faculté de Médecine, Université Laval, Québec G1K 7P4, Canada
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25
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The changing epidemiology of Burkholderia species infection at an adult cystic fibrosis centre. J Cyst Fibros 2008; 7:368-72. [DOI: 10.1016/j.jcf.2008.01.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2007] [Revised: 12/19/2007] [Accepted: 01/11/2008] [Indexed: 11/17/2022]
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26
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Perron GG, Gonzalez A, Buckling A. The rate of environmental change drives adaptation to an antibiotic sink. J Evol Biol 2008; 21:1724-31. [PMID: 18681913 DOI: 10.1111/j.1420-9101.2008.01596.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Recent accelerated trends of human-induced global changes are providing many examples of adaptation to novel environments. Although the rate of environmental change can vary dramatically, its effect on evolving populations is unknown. A crucial feature explaining the adaptation to harsh environments is the supply of beneficial mutations via immigration from a 'source' population. In this study, we tested the effect of immigration on adaptation to increasing concentrations of antibiotics. Using experimental population of Pseudomonas aeruginosa, a pathogenic bacterium, we show that higher immigration rates and a slow increase in antibiotic concentration result in a more rapid evolution of resistance; however, a high immigration rate combined with rapid increases in concentration resulted in higher maximal levels of resistance. These findings, which support recent theoretical work, have important implications for the control of antibiotic resistance because they show that rapid rates of change can produce variants with the ability to resist future treatments.
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Affiliation(s)
- G G Perron
- Department of Zoology, University of Oxford, Oxford, UK
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27
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Ullrich G, Wiedau S, Schulz W, Steinkamp G. Parental knowledge and behaviour to prevent environmental P. aeruginosa acquisition in their children with CF. J Cyst Fibros 2008; 7:231-7. [DOI: 10.1016/j.jcf.2007.09.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2007] [Revised: 09/19/2007] [Accepted: 09/26/2007] [Indexed: 10/22/2022]
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28
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Nichols D, Chmiel J, Berger M. Chronic inflammation in the cystic fibrosis lung: alterations in inter- and intracellular signaling. Clin Rev Allergy Immunol 2008; 34:146-62. [PMID: 17960347 DOI: 10.1007/s12016-007-8039-9] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A vicious cycle of airway obstruction, infection, and inflammation continues to cause most of the morbidity and mortality in cystic fibrosis (CF). Mutations that result in decreased expression or function of the membrane Cl(-) channel, cystic fibrosis transmembrane regulator (CFTR), result in a decrease in the volume (and hence the depth) of liquid on the airway surface, impaired ciliary function, and dehydrated glandular secretions. In turn, these abnormalities contribute to a milieu, which promotes chronic infection with a limited but unique spectrum of microorganisms. Defects in CFTR also perturb regulation of several intracellular signaling pathways including signal transducers and activator of transcription, I-kappaB and nuclear factor-kappa B, and low molecular weight GTPases. Together, these abnormalities result in excessive production of NF-kappaB dependent cytokines such as interleukin (IL)-1, tumor necrosis factor (TNF), IL-6, and IL-8. There are decreased responses to interferon gamma and transforming growth factor beta leading to decreased production of iNOS and NO. Abnormalities of lipid mediators and decreased secretion of counter/regulatory cytokines have also been reported. Together, these effects combine to create a chronic inflammatory process, which damages and obstructs the airways, and eventually claims the life of the patient.
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Affiliation(s)
- David Nichols
- Pulmonology and Allergy-Immunology Divisions, Department of Pediatrics, Case Western Reserve University School of Medicine, Rainbow, Babies and Children's Hospital, Cleveland, OH 44106, USA
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29
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Correia S, Nascimento C, Pereira L, Cunha MV, Sá-Correia I, Barreto C. Infecção respiratória por bactérias do complexo Burkholderia cepacia: Evolução clínica em doentes com fibrose quística. REVISTA PORTUGUESA DE PNEUMOLOGIA 2008. [DOI: 10.1016/s0873-2159(15)30216-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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30
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Norman RS, Stone JW, Gole A, Murphy CJ, Sabo-Attwood TL. Targeted photothermal lysis of the pathogenic bacteria, Pseudomonas aeruginosa, with gold nanorods. NANO LETTERS 2008; 8:302-6. [PMID: 18062714 DOI: 10.1021/nl0727056] [Citation(s) in RCA: 313] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Increases in the prevalence of antibiotic resistant bacteria require new approaches for the treatment of infectious bacterial pathogens. It is now clear that a nanotechnology-driven approach using nanoparticles to selectively target and destroy pathogenic bacteria can be successfully implemented. We have explored this approach by using gold nanorods that have been covalently linked to primary antibodies to selectively destroy the pathogenic Gram-negative bacterium, Pseudomonas aeruginosa. We find that, following nanorod attachment to the bacterial cell surface, exposure to near-infrared radiation results in a significant reduction in bacterial cell viability.
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Affiliation(s)
- R Sean Norman
- Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, South Carolina 29208, USA
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31
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Perron GG, Gonzalez A, Buckling A. Source-sink dynamics shape the evolution of antibiotic resistance and its pleiotropic fitness cost. Proc Biol Sci 2007; 274:2351-6. [PMID: 17650474 PMCID: PMC2288555 DOI: 10.1098/rspb.2007.0640] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Understanding the conditions that favour the evolution and maintenance of antibiotic resistance is the central goal of epidemiology. A crucial feature explaining the adaptation to harsh, or 'sink', environments is the supply of beneficial mutations via migration from a 'source' population. Given that antibiotic resistance is frequently associated with antagonistic pleiotropic fitness costs, increased migration rate is predicted not only to increase the rate of resistance evolution but also to increase the probability of fixation of resistance mutations with minimal fitness costs. Here we report in vitro experiments using the nosocomial pathogenic bacterium Pseudomonas aeruginosa that support these predictions: increasing rate of migration into environments containing antibiotics increased the rate of resistance evolution and decreased the associated costs of resistance. Consistent with previous theoretical work, we found that resistance evolution arose more rapidly in the presence of a single antibiotic than two. Evolution of resistance was also more rapid when bacteria were subjected to sequential exposure with two antibiotics (cycling therapy) compared with simultaneous exposure (bi-therapy). Furthermore, pleiotropic fitness costs of resistance to two antibiotics were higher than for one antibiotic, and were also higher under bi-therapy than cycling therapy, although the cost of resistance depended on the order of the antibiotics through time. These results may be relevant to the clinical setting where immigration is known to be important between chemotherapeutically treated patients, and demonstrate the importance of ecological and evolutionary dynamics in the control of antibiotic resistance.
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Affiliation(s)
- Gabriel G Perron
- Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK.
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Abstract
Over the past decade, non-fermenting Gram-negative bacteria have emerged as important opportunistic pathogens in the increasing population of patients who are immunocompromised by their disease or medical treatment. These bacteria are assisted by their ubiquitous distribution in the environment and have a propensity for multiple, intrinsic or acquired drug resistance. The infections that they cause now pose significant problems in terms of treatment and infection control, whilst the commonly observed rapid emergence of bacterial resistance to new antimicrobial compounds raises concerns regarding the clinical lifespan of these agents. Studies are urgently required to assess whether combination therapy can improve the long-term utility of new drugs in the treatment of patients infected with non-fermenters.
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Affiliation(s)
- D A Enoch
- Clinical Microbiology and Public Health Laboratory, Addenbrooke's Hospital, Hills Road, Cambridge CB2 2QW, UK.
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33
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Vosahlikova S, Drevinek P, Cinek O, Pohunek P, Maixnerova M, Urbaskova P, van den Reijden TJK, Dijkshoorn L, Nemec A. High genotypic diversity of Pseudomonas aeruginosa strains isolated from patients with cystic fibrosis in the Czech Republic. Res Microbiol 2007; 158:324-9. [PMID: 17448645 DOI: 10.1016/j.resmic.2007.02.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2006] [Revised: 02/09/2007] [Accepted: 02/11/2007] [Indexed: 11/22/2022]
Abstract
Over the last decade, epidemic and frequently multidrug-resistant Pseudomonas aeruginosa has increasingly been found among European cystic fibrosis (CF) patients. In the Czech Republic, more than half of the registered CF patients attend the Prague CF centre. At this centre, a Burkholderia cenocepacia strain was recently found to have spread among the patients. The aim of the present study was to assess whether P. aeruginosa isolates from patients at this centre were also genetically related and, if so, whether they were multidrug-resistant. We investigated a collection of 69 isolates from as many patients who represented 80% of the total number of P. aeruginosa-positive patients in 2004. The organisms were typed by AFLP and SpeI macrorestriction analyses (PFGE). Using these methods, 44 unique strains and nine groups of two to five isolates each were distinguished. Among these groups, two each had a prevalence of 7% in the patient population, while others had a prevalence of < or =3%. The diversity observed with PFGE was largely in agreement with the diversity found by AFLP analysis. All isolates were susceptible to colistin; 94-96% were susceptible to piperacillin, ceftazidime, cefepime, meropenem, amikacin or tobramycin; and 84-87% were susceptible to ciprofloxacin, gentamicin or netilmicin. In conclusion, the organisms recovered from Czech CF patients showed high genotypic diversity and good susceptibility to antipseudomonal agents. The absence of highly epidemic P. aeruginosa strains may result from infection control measures taken upon recognition of the epidemic B. cenocepacia.
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Affiliation(s)
- Sarka Vosahlikova
- Department of Paediatrics, 2nd Medical School, Charles University in Prague, Uvalu 84, 15006 Prague 5, Czech Republic
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Evidence supporting isolation measures for prevention of infection with respiratory pathogens in cystic fibrosis. J Hosp Infect 2007. [DOI: 10.1016/j.jhin.2006.12.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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35
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Govan JRW, Brown AR, Jones AM. Evolving epidemiology of Pseudomonas aeruginosa and the Burkholderia cepacia complex in cystic fibrosis lung infection. Future Microbiol 2007; 2:153-64. [PMID: 17661652 DOI: 10.2217/17460913.2.2.153] [Citation(s) in RCA: 128] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The morbidity and mortality of patients with cystic fibrosis (CF) is primarily determined by chronic and debilitating lung infections caused by a surprisingly narrow spectrum of bacterial pathogens. Pseudomonas aeruginosa is by far the most prevalent life-threatening CF pathogen. In the absence of aggressive early therapy, it infects the majority of adult patients and determines long-term survival. The epidemiology of CF pulmonary infections continues to evolve. Amongst the most recent CF pathogens to have emerged are a group of closely related bacteria, known as the Burkholderia cepacia complex. These organisms are a particular challenge due to inherent antibiotic resistance, the potential for patient-to-patient spread, and the risk of ‘cepacia syndrome’, a rapid fulminating pneumonia sometimes accompanied by bacteremia. Strict cross-infection control was prompted by early epidemiological experience of the B. cepacia complex and is essential in the management of all CF pathogens.
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Affiliation(s)
- John R W Govan
- University of Edinburgh, Cystic Fibrosis Group, Centre for Infectious Diseases, Edinburgh, UK.
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Høiby N, Johansen HK. Isolation measures for prevention of infection with respiratory pathogens in cystic fibrosis: a systematic review? J Hosp Infect 2007; 65:374-5; author reply 375-6. [PMID: 17275952 DOI: 10.1016/j.jhin.2006.11.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2006] [Accepted: 11/29/2006] [Indexed: 10/23/2022]
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