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Dallal Bashi YH, Ali A, Al Ayoub Y, Assi KH, Mairs R, McCarthy HO, Tunney MM, Kett VL. Inhaled dry powder liposomal azithromycin for treatment of chronic lower respiratory tract infection. Int J Pharm 2024; 653:123841. [PMID: 38266939 DOI: 10.1016/j.ijpharm.2024.123841] [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: 10/06/2023] [Revised: 01/05/2024] [Accepted: 01/20/2024] [Indexed: 01/26/2024]
Abstract
A dry powder inhaled liposomal azithromycin formulation was developed for the treatment of chronic respiratory diseases such as cystic fibrosis and bronchiectasis. Key properties including liposome size, charge and encapsulation efficiency powder size, shape, glass transition temperature (Tg), water content and in vitro respiratory deposition were determined. Antimicrobial activity against cystic fibrosis (CF) respiratory pathogens was determined by MIC, MBC and biofilm assays. Cytotoxicity and cellular uptake studies were performed using A549 cells. The average liposome size was 105 nm, charge was 55 mV and encapsulation efficiency was 75 %. The mean powder particle size d[v,50] of 4.54 µm and Mass Median Aerodynamic Diameter (MMAD) was 5.23 µm with a mean Tg of 76˚C and water content of 2.1 %. These excellent physicochemical characteristics were maintained over one year. Liposomal loaded azithromycin demonstrated enhanced activity against P. aeruginosa clinical isolates grown in biofilm. The formulation was rapidly delivered into bacterial cells with > 75 % uptake in 1 h. Rapid uptake into A549 cells via a cholesterol-dependent endocytosis pathway with no cytotoxic effects apparent. These data demonstrate that this formulation could offer benefits over current treatment regimens for people with chronic respiratory infection.
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Affiliation(s)
| | - Ahlam Ali
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Yuosef Al Ayoub
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK; School of Pharmacy, University of Bradford, UK
| | - Khaled H Assi
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK; School of Pharmacy, University of Bradford, UK
| | - Rachel Mairs
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Helen O McCarthy
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Michael M Tunney
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Vicky L Kett
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK.
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Pailhoriès H, Herrmann JL, Velo-Suarez L, Lamoureux C, Beauruelle C, Burgel PR, Héry-Arnaud G. Antibiotic resistance in chronic respiratory diseases: from susceptibility testing to the resistome. Eur Respir Rev 2022; 31:31/164/210259. [PMID: 35613743 DOI: 10.1183/16000617.0259-2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Accepted: 03/02/2022] [Indexed: 12/28/2022] Open
Abstract
The development of resistome analysis, i.e. the comprehensive analysis of antibiotic-resistance genes (ARGs), is enabling a better understanding of the mechanisms of antibiotic-resistance emergence. The respiratory microbiome is a dynamic and interactive network of bacteria, with a set of ARGs that could influence the response to antibiotics. Viruses such as bacteriophages, potential carriers of ARGs, may also form part of this respiratory resistome. Chronic respiratory diseases (CRDs) such as cystic fibrosis, severe asthma, chronic obstructive pulmonary disease and bronchiectasis, managed with long-term antibiotic therapies, lead to multidrug resistance. Antibiotic susceptibility testing provides a partial view of the bacterial response to antibiotics in the complex lung environment. Assessing the ARG network would allow personalised, targeted therapeutic strategies and suitable antibiotic stewardship in CRDs, depending on individual resistome and microbiome signatures. This review summarises the influence of pulmonary antibiotic protocols on the respiratory microbiome, detailing the variable consequences according to antibiotic class and duration of treatment. The different resistome-profiling methods are explained to clarify their respective place in antibiotic-resistance analysis in the lungs. Finally, this review details current knowledge on the respiratory resistome related to therapeutic strategies and provides insight into the application of resistome analysis to counter the emergence of multidrug-resistant respiratory pathogens.
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Affiliation(s)
- Hélène Pailhoriès
- Laboratoire de Bactériologie, Institut de Biologie en Santé - PBH, CHU Angers, Angers, France.,HIFIH Laboratory UPRES EA3859, SFR ICAT 4208, Angers University, Angers, France
| | - Jean-Louis Herrmann
- Université Paris-Saclay, UVSQ, INSERM, Infection and Inflammation, Montigny-le-Bretonneux, France.,AP-HP, Groupe Hospitalo-Universitaire Paris-Saclay, Hôpital Raymond Poincaré, Garches, France
| | - Lourdes Velo-Suarez
- Brest Center for Microbiota Analysis (CBAM), Brest University Hospital, Brest, France
| | - Claudie Lamoureux
- Dept of Bacteriology, Virology, Hospital Hygiene, and Parasitology-Mycology, Brest University Hospital, Brest, France.,Université de Brest, INSERM, EFS, UMR 1078, GGB, Brest, France
| | - Clémence Beauruelle
- Dept of Bacteriology, Virology, Hospital Hygiene, and Parasitology-Mycology, Brest University Hospital, Brest, France.,Université de Brest, INSERM, EFS, UMR 1078, GGB, Brest, France
| | - Pierre-Régis Burgel
- Respiratory Medicine and National Cystic Fibrosis Reference Center, Cochin Hospital, Assistance Publique-Hôpitaux de Paris, Université de Paris, Institut Cochin, INSERM U1016, Paris, France
| | - Geneviève Héry-Arnaud
- Brest Center for Microbiota Analysis (CBAM), Brest University Hospital, Brest, France .,Dept of Bacteriology, Virology, Hospital Hygiene, and Parasitology-Mycology, Brest University Hospital, Brest, France.,Université de Brest, INSERM, EFS, UMR 1078, GGB, Brest, France
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3
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Felton E, Burrell A, Chaney H, Sami I, Koumbourlis AC, Freishtat RJ, Crandall KA, Hahn A. Inflammation in children with cystic fibrosis: contribution of bacterial production of long-chain fatty acids. Pediatr Res 2021; 90:99-108. [PMID: 33654282 PMCID: PMC8370878 DOI: 10.1038/s41390-021-01419-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 02/02/2021] [Indexed: 01/12/2023]
Abstract
BACKGROUND Cystic fibrosis (CF) affects >70,000 people worldwide, yet the microbiologic trigger for pulmonary exacerbations (PExs) remains unknown. The objective of this study was to identify changes in bacterial metabolic pathways associated with clinical status. METHODS Respiratory samples were collected at hospital admission for PEx, end of intravenous (IV) antibiotic treatment, and follow-up from 27 hospitalized children with CF. Bacterial DNA was extracted and shotgun DNA sequencing was performed. MetaPhlAn2 and HUMAnN2 were used to evaluate bacterial taxonomic and pathway relative abundance, while DESeq2 was used to evaluate differential abundance based on clinical status. RESULTS The mean age of study participants was 10 years; 85% received combination IV antibiotic therapy (beta-lactam plus a second agent). Long-chain fatty acid (LCFA) biosynthesis pathways were upregulated in follow-up samples compared to end of treatment: gondoate (p = 0.012), oleate (p = 0.048), palmitoleate (p = 0.043), and pathways of fatty acid elongation (p = 0.012). Achromobacter xylosoxidans and Escherichia sp. were also more prevalent in follow-up compared to PEx (p < 0.001). CONCLUSIONS LCFAs may be associated with persistent infection of opportunistic pathogens. Future studies should more closely investigate the role of LCFA production by lung bacteria in the transition from baseline wellness to PEx in persons with CF. IMPACT Increased levels of LCFAs are found after IV antibiotic treatment in persons with CF. LCFAs have previously been associated with increased lung inflammation in asthma. This is the first report of LCFAs in the airway of persons with CF. This research provides support that bacterial production of LCFAs may be a contributor to inflammation in persons with CF. Future studies should evaluate LCFAs as predictors of future PExs.
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Affiliation(s)
- Erin Felton
- grid.253615.60000 0004 1936 9510School of Medicine and Health Sciences, George Washington University, Washington, DC USA
| | - Aszia Burrell
- grid.239560.b0000 0004 0482 1586Center for Genetic Medicine Research, Children’s National Research Institute, Washington, DC USA
| | - Hollis Chaney
- grid.253615.60000 0004 1936 9510Department of Pediatrics, George Washington University School of Medicine and Health Sciences, Washington, DC USA ,grid.239560.b0000 0004 0482 1586Division of Pulmonary and Sleep Medicine, Children’s National Hospital, Washington, DC USA
| | - Iman Sami
- grid.253615.60000 0004 1936 9510Department of Pediatrics, George Washington University School of Medicine and Health Sciences, Washington, DC USA ,grid.239560.b0000 0004 0482 1586Division of Pulmonary and Sleep Medicine, Children’s National Hospital, Washington, DC USA
| | - Anastassios C. Koumbourlis
- grid.253615.60000 0004 1936 9510Department of Pediatrics, George Washington University School of Medicine and Health Sciences, Washington, DC USA ,grid.239560.b0000 0004 0482 1586Division of Pulmonary and Sleep Medicine, Children’s National Hospital, Washington, DC USA
| | - Robert J. Freishtat
- grid.239560.b0000 0004 0482 1586Center for Genetic Medicine Research, Children’s National Research Institute, Washington, DC USA ,grid.253615.60000 0004 1936 9510Department of Pediatrics, George Washington University School of Medicine and Health Sciences, Washington, DC USA ,grid.239560.b0000 0004 0482 1586Division of Emergency Medicine, Children’s National Hospital, Washington, DC USA
| | - Keith A. Crandall
- grid.253615.60000 0004 1936 9510Department of Biostatistics and Bioinformatics, Computational Biology Institute, Milken Institute School of Public Health, George Washington University, Washington, DC USA
| | - Andrea Hahn
- Center for Genetic Medicine Research, Children's National Research Institute, Washington, DC, USA. .,Department of Pediatrics, George Washington University School of Medicine and Health Sciences, Washington, DC, USA. .,Division of Infectious Disease, Children's National Hospital, Washington, DC, USA.
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4
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Draft Genome Sequence of Streptococcus anginosus UMB7768, Isolated from a Woman with Recurrent UTI Symptoms. Microbiol Resour Announc 2020; 9:9/21/e00418-20. [PMID: 32439677 PMCID: PMC7242679 DOI: 10.1128/mra.00418-20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Streptococcus anginosus recently was implicated as a pathogen involved in urinary tract infections. A strain of S. anginosus was isolated from the female urogenital tract. Here, we present the draft genome sequence of S. anginosus strain UMB7768. Streptococcus anginosus recently was implicated as a pathogen involved in urinary tract infections. A strain of S. anginosus was isolated from the female urogenital tract. Here, we present the draft genome sequence of S. anginosus strain UMB7768.
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Pronost P, Tromeur C. [Azithromycine and chronic bronchial diseases: For which patients? For which benefits? With what modalities?]. Rev Med Interne 2019; 40:368-372. [PMID: 30857823 DOI: 10.1016/j.revmed.2019.02.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 01/30/2019] [Accepted: 02/12/2019] [Indexed: 11/25/2022]
Abstract
Azithromycin is a macrolide widely used in chronic bronchial diseases due to its anti-inflammatory properties. This treatment is prescribed to patients with bronchiectasis, asthma and severe chronic obstructive pulmonary disease who present more than 3 exacerbations per year or a deterioration of respiratory function despite an optimal treatment. Macrolides decrease the number of exacerbation but azythromycine must be prescribed carefully. Indeed, it involves potential cardiovascular and otological toxicities and the emergence of resistant bacteria. In addition, studies remain insufficient to establish the optimal dosage and duration of azithromycine.
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Affiliation(s)
- P Pronost
- Département de médecine interne et pneumologie, hôpital de la Cavale-Blanche, CHRU de Brest, boulevard Tanguy-Prigent, 29200 Brest, France.
| | - C Tromeur
- Département de médecine interne et pneumologie, hôpital de la Cavale-Blanche, CHRU de Brest, boulevard Tanguy-Prigent, 29200 Brest, France; Groupe d'étude de la thrombose de Bretagne Occidentale, équipe d'accueil 3878, CHRU de Brest, 29200 Brest, France; Centre d'investigation clinique, Inserm 1412, université de Bretagne Occidentale, 29200 Brest, France
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6
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Sites of infection associated with Streptococcus anginosus group among children. J Infect Chemother 2017; 24:99-102. [PMID: 29050796 DOI: 10.1016/j.jiac.2017.09.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 07/26/2017] [Accepted: 09/16/2017] [Indexed: 11/20/2022]
Abstract
Streptococcus anginosus group (SAG) are parts of normal flora of the oral cavity and associated with abscess forming in various sites on the body. Although the clinical features of infections caused by each member of the SAG in adults has been reported, it has not well been known in children. The aim of this study was to clarify the site of infections associated with individual SAG species among children. Medical records from March 2010 to July 2016 were reviewed at Tokyo Metropolitan Children's Medical Center. Any SAG species (S. anginosus, S. constellatus, or S. intermedius) isolated from clinical samples and recorded in the microbiological database were included for analysis. Analysis of 52 infectious episodes found that S. anginosus was most frequently isolated from the genitourinary tract, and 73% of genitourinary tract infection was balanoposthitis. All genitourinary tract infections were associated with S. anginosus. These findings were different from those of a previous study of adults. Of all the patients, 45 patients (87%) had polymicrobial infections. More than 70% of patients infected by S. anginosus and S. constellatus were co-infected by obligate anaerobes, in comparison with only 21% of S. intermedius cases. Among the obligate anaerobes species, Bacteroides spp. was significantly accompanied with S. anginosus. Susceptibility to penicillin, ampicillin, cefotaxime, erythromycin, clindamycin, levofloxacin, and vancomycin was 100%, 100%, 100%, 77%, 89%, 97% and 100%, respectively. S. anginosus was often isolated from balanoposthitis among children.
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7
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Skolnik K, Nguyen A, Thornton CS, Waddell B, Williamson T, Rabin HR, Parkins MD. Group B streptococcus (GBS) is an important pathogen in human disease- but what about in cystic fibrosis? BMC Infect Dis 2017; 17:660. [PMID: 28969684 PMCID: PMC5625721 DOI: 10.1186/s12879-017-2729-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2016] [Accepted: 09/12/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Group B Streptococcus (GBS) is a common commensal capable of causing severe invasive infections. Most GBS infections occur in neonates (often as pneumonia). GBS can also cause infection in adults with diabetes and other immunological impairments but rarely leads to pneumonia in adults. GBS has occasionally been found in the sputum of Cystic Fibrosis (CF) patients, an inherited condition known for progressive lung disease. However, the epidemiology and clinical significance of GBS in CF are not understood. METHODS We retrospectively reviewed a large single-centre adult CF population with an associated comprehensive, prospectively collected bacterial biobank beginning in 1978. We identified all individuals with GBS isolated from their sputum on at least one occasion. The primary outcome was risk of pulmonary exacerbation (PEx) at the time of the first GBS isolate compared to the preceding visit. Secondary outcomes included determining: prevalence of GBS infection in a CF population, whether GBS infections where transient or persistent, whether GBS strains were shared among patients, change in % predicted FEV1 at the time of GBS isolate compared to the preceding visit, PEx frequency after the first GBS isolate, change in % predicted FEV1 after the first GBS isolate, and complications of GBS infection. RESULTS GBS was uncommon, infecting 3.5% (11/318) adults within our cohort. Only three individuals developed persistent GBS infection, all lasting > 12 months. There were no shared GBS strains among patients. PEx risk was not increased at initial GBS isolation (RR 5.0, CI 0.69-36.1, p=0.10). In the two years preceding initial GBS isolation compared to the two following years, there was no difference in PEx frequency (median 2, range 0-4 vs 1, range 0 to 5, respectively, p=0.42) or lung function decline, as measured by % predicted FEV1, (median -1.0%, range -19 to 7% vs median -6.0%, range -18 to 22%, p=0.86). There were no invasive GBS infections. CONCLUSION In adults with CF, GBS is uncommon and is generally a transient colonizer of the lower airways. Despite the presence of structural lung disease and impaired innate immunity in CF, incident GBS infection did not increase PEx risk, PEx frequency, rate of lung function decline, or other adverse clinical outcomes.
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Affiliation(s)
- Kate Skolnik
- Department of Medicine, University of Calgary, 7007 14th Street SW, Calgary, AB, T2V 1P9, Canada. .,Department of Community Health Sciences, University of Calgary, Third Floor TRW Building, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada.
| | - Austin Nguyen
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N 4N1, Canada
| | - Christina S Thornton
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N 4N1, Canada
| | - Barbara Waddell
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N 4N1, Canada
| | - Tyler Williamson
- Department of Community Health Sciences, University of Calgary, Third Floor TRW Building, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada
| | - Harvey R Rabin
- Department of Medicine, University of Calgary, 7007 14th Street SW, Calgary, AB, T2V 1P9, Canada.,Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N 4N1, Canada
| | - Michael D Parkins
- Department of Medicine, University of Calgary, 7007 14th Street SW, Calgary, AB, T2V 1P9, Canada.,Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N 4N1, Canada
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8
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Draft Genome Sequence of Streptococcus anginosus BVI, a New Vaginal Pathogen Candidate. GENOME ANNOUNCEMENTS 2016; 4:4/6/e01417-16. [PMID: 27979955 PMCID: PMC5159588 DOI: 10.1128/genomea.01417-16] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Streptococcus anginosus is a pathogen implicated in urogenital and gastroinstestinal tract infections. Here, we report the draft genome sequence of S. anginosus BVI, isolated from a bacterial vaginosis patient attending a prenatal care unit in Cali, Colombia. The genome sequence of BVI consists of 2,014,025 bp, encoding 2,008 predicted proteins.
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9
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Join-Lambert O, Coignard-Biehler H, Jais JP, Delage M, Guet-Revillet H, Poirée S, Duchatelet S, Jullien V, Hovnanian A, Lortholary O, Nassif X, Nassif A. Efficacy of ertapenem in severe hidradenitis suppurativa: a pilot study in a cohort of 30 consecutive patients. J Antimicrob Chemother 2015; 71:513-20. [PMID: 26565016 DOI: 10.1093/jac/dkv361] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 10/02/2015] [Indexed: 12/22/2022] Open
Abstract
OBJECTIVES Hidradenitis suppurativa (HS) is an inflammatory skin disease typically localized in the axillae and inguinal and perineal areas. In the absence of standardized medical treatment, severe HS patients present chronic suppurative lesions with polymicrobial anaerobic abscesses. Wide surgery is the cornerstone treatment of severe HS, but surgical indications are limited by the extent of lesions. Intravenous broad-spectrum antibiotics may help control HS, but their efficacy is not documented. This study was designed to assess the efficacy of a 6 week course of ertapenem (1 g daily) and of antibiotic consolidation treatments for 6 months (M6) in severe HS. PATIENTS AND METHODS Thirty consecutive patients with severe HS were retrospectively included in this study. The clinical severity of HS was assessed using the Sartorius score, which takes into account the number and severity of lesions. RESULTS The median (IQR) Sartorius score dropped from 49.5 (28-62) at baseline to 19.0 (12-28) after ertapenem (P < 10(-4)). Five patients were lost to follow-up thereafter. At M6 the Sartorius score further decreased for the 16 patients who received continuous consolidation treatments, since 59% of HS areas reached clinical remission at M6 (i.e. absence of any inflammatory symptoms, P < 10(-4)). Nine patients interrupted or received intermittent consolidation treatments due to poor observance or irregular follow-up. Their Sartorius score stopped improving or returned to baseline. No major adverse event occurred. CONCLUSIONS Ertapenem can dramatically improve severe HS. Consolidation treatments are needed to further improve HS and are mandatory to prevent relapses. Combined with surgery, optimized antibiotic treatments may be promising in severe HS.
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Affiliation(s)
- Olivier Join-Lambert
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France Laboratoire de Microbiologie, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France Centre d'Infectiologie Necker-Pasteur, Paris, France Inserm U1151, eq. 11, Paris, France
| | - Hélène Coignard-Biehler
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France Centre d'Infectiologie Necker-Pasteur, Paris, France Service des Maladies Infectieuses et Tropicales, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Jean-Philippe Jais
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France Service d'Informatique Médicale et de Biostatistiques, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France Inserm U1138, eq. 22, Paris, France
| | - Maïa Delage
- Centre d'Infectiologie Necker-Pasteur, Paris, France Service de Dermatologie, Hôpital Avicenne, Assistance Publique-Hôpitaux de Paris, Bobigny, France Institut Pasteur, Centre Médical, Paris, France
| | - Hélène Guet-Revillet
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France Laboratoire de Microbiologie, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France Centre d'Infectiologie Necker-Pasteur, Paris, France Inserm U1151, eq. 11, Paris, France
| | - Sylvain Poirée
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France Service de Radiologie Adulte, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Sabine Duchatelet
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France Inserm U1163, Laboratory of Genetic Skin Diseases: From Disease Mechanism to Therapies, Imagine Institute, Paris, France
| | - Vincent Jullien
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France Inserm U663, Paris, France
| | - Alain Hovnanian
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France Inserm U1163, Laboratory of Genetic Skin Diseases: From Disease Mechanism to Therapies, Imagine Institute, Paris, France
| | - Olivier Lortholary
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France Centre d'Infectiologie Necker-Pasteur, Paris, France Service des Maladies Infectieuses et Tropicales, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Xavier Nassif
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France Laboratoire de Microbiologie, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France Centre d'Infectiologie Necker-Pasteur, Paris, France Inserm U1151, eq. 11, Paris, France
| | - Aude Nassif
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France Centre d'Infectiologie Necker-Pasteur, Paris, France Service des Maladies Infectieuses et Tropicales, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France Institut Pasteur, Centre Médical, Paris, France
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10
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Thornton CS, Grinwis ME, Sibley CD, Parkins MD, Rabin HR, Surette MG. Antibiotic susceptibility and molecular mechanisms of macrolide resistance in streptococci isolated from adult cystic fibrosis patients. J Med Microbiol 2015; 64:1375-1386. [PMID: 26408040 DOI: 10.1099/jmm.0.000172] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The cystic fibrosis (CF) airways are colonized by polymicrobial communities with high bacterial load and are influenced by frequent antibiotic exposures. This community includes diverse streptococci, some of which have been directly or indirectly associated with pulmonary exacerbations. As many streptococci are naturally competent, horizontal transfer of antibiotic-resistant determinants coupled with frequent and/or chronic antibiotic exposure may contribute to high resistance rates. In this study, we assessed antibiotic resistance in 413 streptococcal isolates from adult CF patients against nine antibiotics relevant in CF treatment. We observed very low rates of cephalosporin resistance [cefepime and ceftriaxone ( < 2%)], and higher rates of resistance to tetracycline (∼34%) and sulfamethoxazole/trimethoprim (∼45%). The highest rate of antibiotic resistance was to the macrolides [azithromycin (56.4%) and erythromycin (51.6%)]. We also investigated the molecular mechanisms of macrolide resistance and found that only half of our macrolide-resistant streptococci isolates contained the mef (efflux pump) or erm (methylation of 23S ribosomal target site) genes. The majority of isolates were, however, found to have point mutations at position 2058 or 2059 of the 23S ribosomal subunit - a molecular mechanism of resistance not commonly reported in the non-pyogenic and non-pneumococcal streptococci, and unique in comparison with previous studies. The high rates of resistance observed here may result in poor outcomes where specific streptococci are contributing to CF airway disease and serve as a reservoir of resistance genes within the CF airway microbiome.
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Affiliation(s)
- Christina S Thornton
- Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Margot E Grinwis
- Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Christopher D Sibley
- Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Michael D Parkins
- Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, Alberta T2N 4N1, Canada.,Department of Medicine, University of Calgary, Calgary, Alberta T2N 4N1, Canada.,Adult Cystic Fibrosis Clinic, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Harvey R Rabin
- Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, Alberta T2N 4N1, Canada.,Department of Medicine, University of Calgary, Calgary, Alberta T2N 4N1, Canada.,Adult Cystic Fibrosis Clinic, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Michael G Surette
- Farncombe Family Digestive Health Research Institute, Department of Medicine, McMaster University, Hamilton, Ontario L8S 4L8, Canada.,Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, Alberta T2N 4N1, Canada
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11
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Prevalence and impact of Streptococcus pneumoniae in adult cystic fibrosis patients: a retrospective chart review and capsular serotyping study. BMC Pulm Med 2015; 15:49. [PMID: 25930152 PMCID: PMC4434824 DOI: 10.1186/s12890-015-0041-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 04/16/2015] [Indexed: 11/20/2022] Open
Abstract
Background Cystic fibrosis (CF) is a genetic disease characterized by complex polymicrobial communities within the lower respiratory tract. S. pneumoniae, while a well-defined pathogen in the general population, has rarely been identified in CF. Furthermore, prevalence studies on Pneumococcus in CF have predominantly focused on the infant and pediatric populations, and outcome data is lacking. Methods Through a review of our comprehensive clinical and microbiologic database from a single adult CF center in Canada from 1978–2013 we sought to determine the incidence, prevalence, serotype and clinical impact of Pneumococcus in adults with CF. Results Only fifteen of 318 adult CF patients (5%) were ever found to have transient Pneumococcus colonization, and none developed persistent infection although length of carriage varied. As all isolates were stored, capsular serotyping could be performed using a multiplex PCR panel. Capsular serotyping revealed a varied distribution of several serotypes within these isolates. Lung function testing at time of incident Pneumococcus isolation was compared with values before and after isolation and showed no significant reduction in spirometry values, nor was there an increased need for rescue antibacterial therapy. Conclusion Within our center, incident Pneumococcus infection is neither common, associated with a disproportionate clinical deterioration nor results in chronic infection.
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Parkins MD, Floto RA. Emerging bacterial pathogens and changing concepts of bacterial pathogenesis in cystic fibrosis. J Cyst Fibros 2015; 14:293-304. [PMID: 25881770 DOI: 10.1016/j.jcf.2015.03.012] [Citation(s) in RCA: 138] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 03/21/2015] [Accepted: 03/22/2015] [Indexed: 12/22/2022]
Abstract
Chronic suppurative lower airway infection is a hallmark feature of cystic fibrosis (CF). Decades of experience in clinical microbiology have enabled the development of improved technologies and approaches for the cultivation and identification of microorganisms from sputum. It is increasingly apparent that the microbial constituents of the lower airways in CF exist in a dynamic state. Indeed, while changes in prevalence of various pathogens occur through ageing, differences exist in successive cohorts of patients and between clinics, regions and countries. Classical pathogens such as Pseudomonas aeruginosa, Burkholderia cepacia complex and Staphylococcus aureus are increasingly being supplemented with new and emerging organisms rarely observed in other areas of medicine. Moreover, it is now recognized that common oropharyngeal organisms, previously presumed to be benign colonizers may contribute to disease progression. As infection remains the leading cause of morbidity and mortality in CF, an understanding of the epidemiology, risk factors for acquisition and natural history of infection including interactions between colonizing bacteria is required. Unified approaches to the study and determination of pathogen status are similarly needed. Furthermore, experienced and evidence-based treatment data is necessary to optimize outcomes for individuals with CF.
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Affiliation(s)
- Michael D Parkins
- Department of Medicine, The University of Calgary, 3330 Hospital Drive NW, Calgary, AB T2N 4N1, Canada; Microbiology, Immunology and Infectious Diseases, The University of Calgary, 3330 Hospital Drive NW, Calgary, AB T2N 4N1, Canada.
| | - R Andres Floto
- Cambridge Institute for Medical Research, University of Cambridge, Papworth Hospital, Cambridge CB23 3RE, UK; Cambridge Centre for Lung Infection, Papworth Hospital, Cambridge CB23 3RE, UK.
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Kaiser JC, Verschoor CP, Surette MG, Bowdish DME. Host cytokine responses distinguish invasive from airway isolates of the Streptococcus milleri/anginosis group. BMC Infect Dis 2014; 14:498. [PMID: 25209732 PMCID: PMC4175566 DOI: 10.1186/1471-2334-14-498] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Accepted: 09/03/2014] [Indexed: 01/13/2023] Open
Abstract
Background The Streptococcus Milleri/Anginosus Group (SMG) colonize mucosal surfaces, especially the airways, and are considered to be normal mucosal microbiota; however, they are a major cause of abscesses, pneumonia and pleural empyema. The production of exoenzymes and virulence factors do not correlate with SMG pathogenicity. Since SMG infections are associated with robust inflammatory responses, we hypothesized that host immune responses might distinguish strains associated with asymptomatic carriage and those associated with fulminant disease. Methods We measured IL1β, TNF, IL10, IL12, IL23, IL17, and IL4 production from human peripheral blood mononuclear cells (PBMCs) stimulated with a panel of clinical isolates from the airways and infections and measured the ability of these isolates to stimulate TLR2. Results Isolates were categorized based on the levels of cytokines they induced from PBMCs (high, intermediate, low). Airway isolates predominantly induced low levels of cytokines and isolates from invasive disease induced higher levels, although about 10% of the strains produced divergent cytokine responses between donors. Interestingly, the donors were most divergent in their production of IL17, IL12 and IL23. Conclusions We propose that the ability to inhibit or avoid an inflammatory response is associated with carriage in the airways and variability in responses between isolates and donors might contribute to susceptibility to disease. Electronic supplementary material The online version of this article (doi:10.1186/1471-2334-14-498) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | - Dawn M E Bowdish
- Department of Pathology & Molecular Medicine, McMaster Immunology Research Centre, McMaster University, 1280 Main St W, Hamilton, ON L8S 4 K1, Canada.
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Abstract
Cystic fibrosis is characterised by chronic polymicrobial infection and inflammation in the airways of patients. Antibiotic treatment regimens, targeting recognised pathogens, have substantially contributed to increased life expectancy of patients with this disease. Although the emergence of antimicrobial resistance and selection of highly antibiotic-resistant bacterial strains is of major concern, the clinical relevance in cystic fibrosis is yet to be defined. Resistance has been identified in recognised cystic fibrosis pathogens and in other bacteria (eg, Prevotella and Streptococcus spp) detected in the airway microbiota, but their role in the pathophysiology of infection and inflammation in chronic lung disease is unclear. Increased antibiotic resistance in cystic fibrosis might be attributed to a range of complex factors including horizontal gene transfer, hypoxia, and biofilm formation. Strategies to manage antimicrobial resistance consist of new antibiotics or localised delivery of antimicrobial agents, iron sequestration, inhibition of quorum-sensing, and resistome analysis. Determination of the contributions of every bacterial species to lung health or disease in cystic fibrosis might also have an important role in the management of antibiotic resistance.
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Affiliation(s)
- Laura J Sherrard
- CF and Airways Microbiology Group, Queen's University Belfast, Belfast, UK; School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - Michael M Tunney
- CF and Airways Microbiology Group, Queen's University Belfast, Belfast, UK; School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - J Stuart Elborn
- CF and Airways Microbiology Group, Queen's University Belfast, Belfast, UK; Centre for Infection and Immunity, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK.
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McCaughey G, Gilpin DF, Elborn JS, Tunney MM. The future of antimicrobial therapy in the era of antibiotic resistance in cystic fibrosis pulmonary infection. Expert Rev Respir Med 2014; 7:385-96. [DOI: 10.1586/17476348.2013.814411] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Gravey F, Galopin S, Grall N, Auzou M, Andremont A, Leclercq R, Cattoir V. Lincosamide resistance mediated by lnu(C) (L phenotype) in a Streptococcus anginosus clinical isolate. J Antimicrob Chemother 2013; 68:2464-7. [PMID: 23812683 DOI: 10.1093/jac/dkt255] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES Unique resistance to lincosamides (L phenotype) due to the production of nucleotidyltransferases (Lnu) is uncommon among Gram-positive bacteria. The aim of the study was to characterize the L phenotype in a clinical isolate of the Streptococcus milleri group. METHODS The strain UCN93 was recovered from neonatal specimens and from the mother's vaginal swab. Identification was confirmed by sequencing of the sodA gene. Antimicrobial susceptibility testing was carried out by the disc diffusion method, while MICs were determined using the agar dilution method. Screening for lnu(A), lnu(B), lnu(C) and lnu(D) genes was performed by PCR. Genetic environment and support were determined by thermal asymmetric interlaced PCR and PCR mapping. The transfer of lincomycin resistance was also attempted by conjugation. RESULTS UCN93 was unambiguously identified as Streptococcus anginosus. It was susceptible to all tested antibiotics, except lincomycin (MIC, 8 mg/L) and tetracycline (2 mg/L). The lnu(C) gene was found to be responsible for the L phenotype. It was shown that lnu(C) was associated with a gene coding for a transposase within a structure similar to the transposon MTnSag1, described once in Streptococcus agalactiae. Since MTnSag1 was found to be mobilized by Tn916 and S. anginosus UCN93 harboured a Tn916 transposon, several attempts at transfer were performed but they all failed. The lnu(C)-containing genetic element was inserted into a chromosomal intergenic sequence of S. anginosus. CONCLUSIONS Since lnu(C) has been detected in only one S. agalactiae clinical isolate so far, this is its second description among clinically relevant streptococci.
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Affiliation(s)
- François Gravey
- CHU de Caen, Service de Microbiologie & CNR de la Résistance aux Antibiotiques (laboratoire associé 'entérocoques et résistances particulières des bactéries à Gram positif'), F-14033 Caen, France
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Sherrard LJ, Graham KA, McGrath SJ, McIlreavey L, Hatch J, Muhlebach MS, Wolfgang MC, Gilpin DF, Elborn JS, Schneiders T, Tunney MM. Antibiotic resistance in Prevotella species isolated from patients with cystic fibrosis. J Antimicrob Chemother 2013; 68:2369-74. [PMID: 23696621 DOI: 10.1093/jac/dkt191] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
OBJECTIVES To compare the antimicrobial susceptibility of Prevotella spp. isolated from cystic fibrosis (CF) and non-CF patients and analyse the impact of antibiotic prescribing in the preceding year on resistance amongst CF isolates. METHODS The susceptibility of 80 CF Prevotella isolates to 12 antibiotics was compared with that of 50 Prevotella isolates from invasive infections in people who did not have CF and 27 Prevotella isolates from healthy controls. RESULTS All isolates were susceptible to chloramphenicol, meropenem and piperacillin/tazobactam, with only four isolates resistant to metronidazole. However, resistance to amoxicillin, ceftazidime and tetracycline was apparent in all groups. Significant differences in clindamycin resistance (UK CF, 56%; UK invasive, 10%) and co-amoxiclav non-susceptibility (UK CF, 32%; UK invasive, 12%) were observed between UK CF and UK invasive isolates. The likelihood of non-susceptibility to clindamycin and co-amoxiclav in UK CF isolates was 5.5-fold and 2.5-fold higher relative to that in UK invasive isolates, respectively. Azithromycin MICs were also significantly higher for CF isolates (P < 0.001), which was associated with current prescription of azithromycin. More than 50% of clinical isolates tested in this study were β-lactamase positive. CONCLUSIONS This study profiles antibiotic susceptibility in Prevotella spp. in CF and demonstrates that meropenem, piperacillin/tazobactam, chloramphenicol and metronidazole are likely to be the most effective antibiotics if treatment is indicated.
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Affiliation(s)
- Laura J Sherrard
- CF & Airways Microbiology Group, Queen's University Belfast, Belfast, UK
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Gaspar MC, Couet W, Olivier JC, Pais AACC, Sousa JJS. Pseudomonas aeruginosa infection in cystic fibrosis lung disease and new perspectives of treatment: a review. Eur J Clin Microbiol Infect Dis 2013; 32:1231-52. [DOI: 10.1007/s10096-013-1876-y] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 04/01/2013] [Indexed: 12/20/2022]
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Abstract
PURPOSE OF REVIEW Culture and molecular approaches have established that lower airway infections are polymicrobial. We consider how this new perspective in cystic fibrosis (CF) may affect treatment choices. RECENT FINDINGS Standard clinical microbiology of CF infection exacerbations often fails to provide indications of microbial causes that may drive the onset of exacerbation and the anticipated bacteriologic responses to the usual parenteral antibiotics prescribed as treatment. Antimicrobial responses by nonclassical members of the CF airway microbiome may explain why most patients clinically improve. These other organisms contribute to disease either directly as pathogens missed by conventional microbiology or through synergy with conventional pathogens. With these considerations, therapy may best be guided by directed antibiotic therapy to numerically significant isolates. An example is the Streptococcus milleri group, which we now believe to represent new pathogens that profile the exacerbations of infection in the CF lung and that necessitate specific antibiotic therapy to prevent loss of lung function and reduce frequency of exacerbations. SUMMARY A comprehensive understanding of airway infections offers the potential for improved disease management in CF patients. Accurate quantitative microbiology will be a prerequisite for routine intervention based on the polymicrobial perspective of CF infection exacerbations.
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Gillanders LJ, Elborn JS, Gilpin DF, Schneiders T, Tunney MM. The airway microbiome in cystic fibrosis: challenges for therapy. ACTA ACUST UNITED AC 2011. [DOI: 10.2217/thy.11.81] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Sibley CD, Surette MG. The polymicrobial nature of airway infections in cystic fibrosis: Cangene Gold Medal Lecture. Can J Microbiol 2011; 57:69-77. [PMID: 21326348 DOI: 10.1139/w10-105] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Microbial communities characterize the airways of cystic fibrosis (CF) patients. Members of these diverse and dynamic communities can be thought of as pathogens, benign commensals, or synergens--organisms not considered pathogens in the traditional sense but with the capacity to alter the pathogenesis of the community through microbe-microbe or polymicrobe-host interactions. Very few bacterial pathogens have been implicated as clinically relevant in CF; however, the CF airway microbiome can be a reservoir of previously unrecognized but clinically relevant organisms. A combination of culture-dependent and culture-independent approaches provides a more comprehensive perspective of CF microbiology than either approach alone. Here we review these concepts, highlight the future challenges for CF microbiology, and discuss the implications for the management of CF airway infections. We suggest that the success of treatment interventions for chronic CF lung disease will rely on the context of the microbes within microbial communities. The microbiology of CF airways may serve as a model to investigate the emergent properties of other clinically relevant microbial communities in the human body.
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Affiliation(s)
- Christopher D Sibley
- Department of Microbiology and Infectious Diseases, University of Calgary, 3330 Hospital Drive NW, Calgary, AB T2N 4N1, Canada.
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Sibley CD, Grinwis ME, Rabin HR, Surette MG. Azithromycin paradox in the treatment of cystic fibrosis airway disease. Future Microbiol 2010; 5:1315-9. [DOI: 10.2217/fmb.10.99] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Evaluation of: Saiman L, Anstead M, Mayer-Hamblett N et al.: Effect of azithromycin on pulmonary function in patients with cystic fibrosis uninfected with Pseudomonas aeruginosa: a randomized controlled trial. JAMA 303(17), 1707–1715 (2010). Chronic airway infection and inflammation are hallmarks of cystic fibrosis (CF). Disease progression can be described as chronic inflammation punctuated by acute exacerbations with overt immunological responses. Macrolide antibiotics, which have both immunomodulatory and antibacterial activities, have been shown to be beneficial in the management of CF airway disease, although the mechanism of action is unknown. It is also unclear whether all patients, particularly those not colonized with Pseudomonas aeruginosa, benefit from this treatment. In this article, Saiman et al. examine the effects of azithromycin on lung function in pediatric and adolescent CF patients who are not colonized with P. aeruginosa. The data indicate beneficial effects of azithromycin treatment and suggest the mechanisms of action of azithromycin is at least partially independent of P. aeruginosa.
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Affiliation(s)
- Christopher D Sibley
- Department of Microbiology & Infectious Diseases, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, T2N 4N1, Canada
| | - Margot E Grinwis
- Department of Microbiology & Infectious Diseases, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, T2N 4N1, Canada
| | - Harvey R Rabin
- Department of Microbiology & Infectious Diseases, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, T2N 4N1, Canada
- Department of Medicine & Adult Cystic Fibrosis Clinic, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, T2N 4N1, Canada
| | - Michael G Surette
- Department of Biochemistry & Molecular Biology, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, T2N 4N1, Canada
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