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Distribution and Characteristics of Bacteria Isolated from Cystic Fibrosis Patients with Pulmonary Exacerbation. THE CANADIAN JOURNAL OF INFECTIOUS DISEASES & MEDICAL MICROBIOLOGY = JOURNAL CANADIEN DES MALADIES INFECTIEUSES ET DE LA MICROBIOLOGIE MEDICALE 2022; 2022:5831139. [PMID: 36593975 PMCID: PMC9805393 DOI: 10.1155/2022/5831139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 11/24/2022] [Accepted: 12/03/2022] [Indexed: 12/25/2022]
Abstract
Background Cystic fibrosis (CF) is an inherited recessive disorder characterized by recurrent and persistent pulmonary infections, resulting in lung function deterioration and early mortality. Methods A cross-sectional study was conducted on the bacterial profile and antibiotic resistance pattern of 103 respiratory specimens from CF patients with signs of pulmonary exacerbation. Antibiotic susceptibility testing and biofilm formation of Staphylococcus aureus and Pseudomonas aeruginosa isolates were performed by the Kirby-Bauer disc diffusion method and microtiter plate assay, respectively. Molecular typing of S. aureus and P. aeruginosa isolates was carried out by spa typing and repetitive extragenic palindromic element PCR. Results In a total of 129 isolates, the most prevalent organisms were S. aureus (55.3%) and P. aeruginosa (41.7%). Other less prevalent bacterial isolates include coagulase-negative staphylococci, Escherichia coli, klebsiella spp., Enterobacter spp., and Achromobacter xylosoxidans. The highest rate of resistance for S. aureus was observed to azithromycin and erythromycin (80%), ciprofloxacin (52.3%), clindamycin (44.6%) and tetracycline (43%). Twenty percent of S. aureus isolates were methicillin-resistant S. aureus (MRSA) and 47.6% were MDR S. aureus. For P. aeruginosa isolates the highest resistance was to cefepime (38.3%) and levofloxacin (33.3%) and 20% showed MDR phenotype. Conclusion Our study demonstrated a significant decline in the prevalence of P. aeruginosa infections in comparison to previous studies. We found S. aureus to be more prevalent in younger patients, whereas mucoid P. aeruginosa showed a shift in prevalence toward older ages. Molecular typing methods showed great diversity between isolates.
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Green HD, Jones AM. Managing Pulmonary Infection in Adults With Cystic Fibrosis: Adult Cystic Fibrosis Series. Chest 2022; 162:66-75. [PMID: 35167860 DOI: 10.1016/j.chest.2022.02.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Revised: 02/04/2022] [Accepted: 02/04/2022] [Indexed: 12/17/2022] Open
Abstract
Cystic fibrosis (CF) is characterized by chronic airway infection and progressive respiratory decline. Historically, a narrow spectrum of bacterial pathogens was believed to comprise the bulk of respiratory infections in CF, with Haemophilus influenzae and Staphylococcus aureus dominating childhood infections, and Pseudomonas aeruginosa or, less commonly, a member of the Burkholderia cepacia complex becoming the dominant infecting organism in adulthood. Today, the landscape is changing for airway infection in CF. The prevalence of "less typical" gram-negative bacterial infections are rising due to a number of factors: the CF population is aging; new therapies are being introduced; antibiotic usage is increasing; diagnostic tests are evolving; and taxonomic changes are being made as new bacterial species are being discovered. Less is known about the clinical relevance and evidence for treatment strategies for many of the other lower prevalence organisms that are encountered in CF. The aim of this article was to discuss the current evidence and recommended strategies for treating airway infection in CF, focusing on bacterial infections.
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Affiliation(s)
- Heather D Green
- Manchester Adult Cystic Fibrosis Centre, Manchester University NHS Foundation Trust, Manchester, England
| | - Andrew M Jones
- Manchester Adult Cystic Fibrosis Centre, Manchester University NHS Foundation Trust, Manchester, England; Division of Infection, Immunity and Respiratory Medicine, University of Manchester, Manchester, England.
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Longitudinal Surveillance and Combination Antimicrobial Susceptibility Testing of Multidrug-Resistant Achromobacter Species from Cystic Fibrosis Patients. Antimicrob Agents Chemother 2020; 64:AAC.01467-20. [PMID: 32816722 DOI: 10.1128/aac.01467-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 08/07/2020] [Indexed: 01/16/2023] Open
Abstract
Achromobacter spp. are recognized as emerging pathogens in patients with cystic fibrosis (CF). Though recent works have established species-level identification using nrdA sequencing, there is a dearth in knowledge relating to species-level antimicrobial susceptibility patterns and antimicrobial combinations, which hampers the use of optimal antimicrobial combinations for the treatment of chronic infections. The aims of this study were to (i) identify at species-level referred Achromobacter isolates, (ii) describe species-level antimicrobial susceptibility profiles, and (iii) determine the most promising antimicrobial combination for chronic Achromobacter infections. A total of 112 multidrug-resistant (MDR) Achromobacter species isolates from 39 patients were identified using nrdA sequencing. Antimicrobial susceptibility and combination testing were carried out using the Etest method. We detected six species of Achromobacter and found that Achromobacter xylosoxidans was the most prevalent species. Interestingly, sequence analysis showed it was responsible for persistent infection (18/28 patients), followed by Achromobacter ruhlandii (2/3 patients). Piperacillin-tazobactam (70.27%) and co-trimoxazole (69.72%) were the most active antimicrobials. Differences were observed in species-level susceptibility to ceftazidime, carbapenems, ticarcillin-clavulanate, and tetracycline. Antimicrobial combinations with co-trimoxazole or tobramycin demonstrate the best synergy, while co-trimoxazole gave the best susceptibility breakpoint index values. This study enriches the understanding of MDR Achromobacter spp. epidemiology and confirms prevalence and chronic colonization of A. xylosoxidans in CF lungs. It presents in vitro data to support the efficacy of new combinations for use in the treatment of chronic Achromobacter infections.
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Price EP, Soler Arango V, Kidd TJ, Fraser TA, Nguyen TK, Bell SC, Sarovich DS. Duplex real-time PCR assay for the simultaneous detection of Achromobacter xylosoxidans and Achromobacter spp. Microb Genom 2020; 6:mgen000406. [PMID: 32667877 PMCID: PMC7478622 DOI: 10.1099/mgen.0.000406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 06/26/2020] [Indexed: 01/10/2023] Open
Abstract
Several members of the Gram-negative environmental bacterial genus Achromobacter are associated with serious infections, with Achromobacter xylosoxidans being the most common. Despite their pathogenic potential, little is understood about these intrinsically drug-resistant bacteria and their role in disease, leading to suboptimal diagnosis and management. Here, we performed comparative genomics for 158 Achromobacter spp. genomes to robustly identify species boundaries, reassign several incorrectly speciated taxa and identify genetic sequences specific for the genus Achromobacter and for A. xylosoxidans. Next, we developed a Black Hole Quencher probe-based duplex real-time PCR assay, Ac-Ax, for the rapid and simultaneous detection of Achromobacter spp. and A. xylosoxidans from both purified colonies and polymicrobial clinical specimens. Ac-Ax was tested on 119 isolates identified as Achromobacter spp. using phenotypic or genotypic methods. In comparison to these routine diagnostic methods, the duplex assay showed superior identification of Achromobacter spp. and A. xylosoxidans, with five Achromobacter isolates failing to amplify with Ac-Ax confirmed to be different genera according to 16S rRNA gene sequencing. Ac-Ax quantified both Achromobacter spp. and A. xylosoxidans down to ~110 genome equivalents and detected down to ~12 and ~1 genome equivalent(s), respectively. Extensive in silico analysis, and laboratory testing of 34 non-Achromobacter isolates and 38 adult cystic fibrosis sputa, confirmed duplex assay specificity and sensitivity. We demonstrate that the Ac-Ax duplex assay provides a robust, sensitive and cost-effective method for the simultaneous detection of all Achromobacter spp. and A. xylosoxidans and will facilitate the rapid and accurate diagnosis of this important group of pathogens.
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Affiliation(s)
- Erin P. Price
- GeneCology Research Centre, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
- Sunshine Coast Health Institute, Birtinya, Queensland, Australia
| | - Valentina Soler Arango
- GeneCology Research Centre, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
- Sunshine Coast Health Institute, Birtinya, Queensland, Australia
| | - Timothy J. Kidd
- School of Chemistry and Molecular Biosciences, Faculty of Science, The University of Queensland, St Lucia, Queensland, Australia
- QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
- Faculty of Medicine, The University of Queensland, Herston, Queensland, Australia
| | - Tamieka A. Fraser
- GeneCology Research Centre, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
- Sunshine Coast Health Institute, Birtinya, Queensland, Australia
| | - Thuy-Khanh Nguyen
- QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Scott C. Bell
- QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
- Faculty of Medicine, The University of Queensland, Herston, Queensland, Australia
- Adult Cystic Fibrosis Centre, The Prince Charles Hospital, Chermside, Queensland, Australia
| | - Derek S. Sarovich
- GeneCology Research Centre, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
- Sunshine Coast Health Institute, Birtinya, Queensland, Australia
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Recio R, Brañas P, Martínez MT, Chaves F, Orellana MA. Effect of respiratory Achromobacter spp. infection on pulmonary function in patients with cystic fibrosis. J Med Microbiol 2018; 67:952-956. [DOI: 10.1099/jmm.0.000763] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- R. Recio
- Department of Clinical Microbiology, Hospital Universitario 12 de Octubre, Madrid, Spain
- Instituto de Investigación Sanitaria Hospital 12 de Octubre (imas12), Madrid, Spain
| | - P. Brañas
- Department of Clinical Microbiology, Hospital Universitario 12 de Octubre, Madrid, Spain
- Instituto de Investigación Sanitaria Hospital 12 de Octubre (imas12), Madrid, Spain
| | - M. T. Martínez
- Instituto de Investigación Sanitaria Hospital 12 de Octubre (imas12), Madrid, Spain
- Cystic Fibrosis Unit, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - F. Chaves
- Department of Clinical Microbiology, Hospital Universitario 12 de Octubre, Madrid, Spain
- Instituto de Investigación Sanitaria Hospital 12 de Octubre (imas12), Madrid, Spain
| | - M. A. Orellana
- Department of Clinical Microbiology, Hospital Universitario 12 de Octubre, Madrid, Spain
- Instituto de Investigación Sanitaria Hospital 12 de Octubre (imas12), Madrid, Spain
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Prevalence and Outcomes of Achromobacter Species Infections in Adults with Cystic Fibrosis: a North American Cohort Study. J Clin Microbiol 2017; 55:2074-2085. [PMID: 28446570 DOI: 10.1128/jcm.02556-16] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2017] [Accepted: 03/20/2017] [Indexed: 02/07/2023] Open
Abstract
Achromobacter species are increasingly being detected in cystic fibrosis (CF) patients, with an unclear epidemiology and impact. We studied a cohort of patients attending a Canadian adult CF clinic who had positive sputum cultures for Achromobacter species in the period from 1984 to 2013. Infection was categorized as transient or persistent (≥50% positive cultures for 1 year). Those with persistent infection were matched 2:1 with age-, sex-, and time-matched controls without a history of Achromobacter infection, and mixed-effects models were used to assess pulmonary exacerbation (PEx) frequency and lung function decline. Isolates from a biobank were retrospectively assessed, identified to the species level by nrdA sequencing, and genotyped using pulsed-field gel electrophoresis (PFGE). Thirty-four patients (11% of those in our clinic), with a median age of 24 years (interquartile range [IQR], 20.3 to 29.8 years), developed Achromobacter infection. Ten patients (29%) developed persistent infection. Persistence did not denote permanence, as most patients ultimately cleared infection, often after years. Patients were more likely to experience PEx at incident isolation than at prior or subsequent visits (odds ratio [OR], 2.7 [95% confidence interval {CI}, 1.2 to 6.7]; P = 0.03). Following persistent infection, there was no difference in annual lung function decline (-1.08% [95% CI, -2.73 to 0.57%] versus -2.74% [95% CI, -4.02 to 1.46%]; P = 0.12) or the odds of PEx (OR, 1.21 [95% CI, 0.45 to 3.28]; P = 0.70). Differential virulence among Achromobacter species was not observed, and no cases of transmission occurred. We demonstrated that incident Achromobacter infection was associated with a greater risk of PEx; however, neither transient nor chronic infection was associated with a worsened long-term prognosis. Large, multicenter studies are needed to clarify the clinical impact, natural history, and transmissibility of Achromobacter.
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Impact of High Diversity of Achromobacter Populations within Cystic Fibrosis Sputum Samples on Antimicrobial Susceptibility Testing. J Clin Microbiol 2016; 55:206-215. [PMID: 27807149 DOI: 10.1128/jcm.01843-16] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Accepted: 10/25/2016] [Indexed: 01/31/2023] Open
Abstract
Chronic colonization by opportunistic environmental bacteria is frequent in the airways of cystic fibrosis (CF) patients. Studies of Pseudomonas aeruginosa evolution during persistence have highlighted the emergence of pathoadaptive genotypes and phenotypes, leading to complex and diversified inpatient colonizing populations also observed at the intraspecimen level. Such diversity, including heterogeneity in resistance profiles, has been considered an adaptive strategy devoted to host persistence. Longitudinal genomic diversity has been shown for the emergent opportunistic pathogen Achromobacter, but phenotypic and genomic diversity has not yet been studied within a simple CF sputum sample. Here, we studied the genomic diversity and antimicrobial resistance heterogeneity of 132 Achromobacter species strains (8 to 27 strains of identical or distinct colonial morphotypes per specimen) recovered from the sputum samples of 9 chronically colonized CF patients. We highlighted the high within-sample and within-morphotype diversity of antimicrobial resistance (disk diffusion) and genomic (pulsed-field gel electrophoresis) profiles. No sputum sample included strains with identical pulsotypes or antibiotic susceptibility patterns. Differences in clinical categorization were observed for the 9 patients and concerned 3 to 11 antibiotics, including antibiotics recommended for use against Achromobacter Within-sample antimicrobial resistance heterogeneity, not predictable from colonial morphology, suggested that it may represent a selective advantage against antibiotics in an Achromobacter persisting population and potentially compromise the antibiotic management of CF airway infections.
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9
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Talbot NP, Flight WG. Severe Achromobacter xylosoxidans infection and loss of sputum bacterial diversity in an adult patient with cystic fibrosis. Paediatr Respir Rev 2016; 20 Suppl:27-9. [PMID: 27374622 DOI: 10.1016/j.prrv.2016.06.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Achromobacter spp. are emerging pathogens in the lungs of patients with cystic fibrosis. We report the case of an adult patient with cystic fibrosis and chronic A. xylosoxidans infection who experienced rapid, progressive clinical deterioration. Metagenomic analysis of the sputum revealed that the airway microbiota was almost entirely dominated by A. xylosoxidans. We review the impact of this organism on lung function and the airway microbiome in cystic fibrosis, and discuss the potential for cross-infection between patients.
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Affiliation(s)
- Nick P Talbot
- Oxford Adult Cystic Fibrosis Centre, Oxford University Hospitals NHS Foundation Trust; Nuffield Department of Medicine, University of Oxford.
| | - William G Flight
- Oxford Adult Cystic Fibrosis Centre, Oxford University Hospitals NHS Foundation Trust
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Cools P, Ho E, Vranckx K, Schelstraete P, Wurth B, Franckx H, Ieven G, Van Simaey L, Van Daele S, Verhulst S, De Baets F, Vaneechoutte M. Epidemic Achromobacter xylosoxidans strain among Belgian cystic fibrosis patients and review of literature. BMC Microbiol 2016; 16:122. [PMID: 27342812 PMCID: PMC4919866 DOI: 10.1186/s12866-016-0736-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 06/08/2016] [Indexed: 12/11/2022] Open
Abstract
Background Achromobacter xylosoxidans is increasingly being recognized as an emerging pathogen in cystic fibrosis. Recent severe infections with A. xylosoxidans in some of our cystic fibrosis (CF) patients led to a re-evaluation of the epidemiology of CF-associated A. xylosoxidans infections in two Belgian reference centres (Antwerp and Ghent). Several of these patients also stayed at the Rehabilitation Centre De Haan (RHC). In total, 59 A. xylosoxidans isolates from 31 patients (including 26 CF patients), collected between 2001 and 2014, were studied. We evaluated Matrix Assisted Laser Desorption Ionisation -Time of Flight mass spectrometry (MALDI-TOF) as an alternative for McRAPD typing. Results Both typing approaches established the presence of a major cluster, comprising isolates, all from 21 CF patients, including from two patients sampled when staying at the RHC a decade ago. This major cluster was the same as the cluster established already a decade ago at the RHC. A minor cluster consisted of 13 isolates from miscellaneous origin. A further seven isolates, including one from a non-CF patient who had stayed recently at the RHC, were singletons. Conclusions Typing results of both methods were similar, indicating transmission of a single clone of A. xylosoxidans among several CF patients from at least two reference centres. Isolates of the same clone were already observed at the RHC, a decade ago. It is difficult to establish to what extent the RHC is the source of transmission, because the epidemic strain was already present when the first epidemiological study in the RHC was carried out. This study also documents the applicability of MALDI-TOF for typing of strains within the species A. xylosoxidans and the need to use the dynamic cutoff algorithm of the BioNumerics® software for correct clustering of the fingerprints. Electronic supplementary material The online version of this article (doi:10.1186/s12866-016-0736-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Piet Cools
- Laboratory Bacteriology Research (LBR), Department of Microbiology, Immunology, and Clinical Chemistry, Faculty of Medicine and Health Sciences, Ghent University, De Pintelaan 185, 9000, Ghent, Belgium
| | - Erwin Ho
- Cystic Fibrosis Centre, Antwerp University Hospital (AUH), Antwerp, Belgium
| | | | | | - Bettina Wurth
- Zeepreventorium (Rehabilitation Centre, RHC), De Haan, Belgium
| | - Hilde Franckx
- Zeepreventorium (Rehabilitation Centre, RHC), De Haan, Belgium
| | - Greet Ieven
- Department of Microbiology, Antwerp University Hospital, Antwerp, Belgium
| | - Leen Van Simaey
- Laboratory Bacteriology Research (LBR), Department of Microbiology, Immunology, and Clinical Chemistry, Faculty of Medicine and Health Sciences, Ghent University, De Pintelaan 185, 9000, Ghent, Belgium
| | - Sabine Van Daele
- Cystic Fibrosis Centre, Ghent University Hospital (GUH), Ghent, Belgium
| | - Stijn Verhulst
- Cystic Fibrosis Centre, Antwerp University Hospital (AUH), Antwerp, Belgium
| | - Frans De Baets
- Cystic Fibrosis Centre, Ghent University Hospital (GUH), Ghent, Belgium
| | - Mario Vaneechoutte
- Laboratory Bacteriology Research (LBR), Department of Microbiology, Immunology, and Clinical Chemistry, Faculty of Medicine and Health Sciences, Ghent University, De Pintelaan 185, 9000, Ghent, Belgium.
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Liu C, Pan F, Guo J, Yan W, Jin Y, Liu C, Qin L, Fang X. Hospital Acquired Pneumonia Due to Achromobacter spp. in a Geriatric Ward in China: Clinical Characteristic, Genome Variability, Biofilm Production, Antibiotic Resistance and Integron in Isolated Strains. Front Microbiol 2016; 7:621. [PMID: 27242678 PMCID: PMC4860489 DOI: 10.3389/fmicb.2016.00621] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 04/15/2016] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Hospital-acquired pneumonia (HAP) due to Achromobacter has become a substantial concern in recent years. However, HAP due to Achromobacter in the elderly is rare. METHODS A retrospective analysis was performed on 15 elderly patients with HAP due to Achromobacter spp., in which the sequence types (STs), integrons, biofilm production and antibiotic resistance of the Achromobacter spp. were examined. RESULTS The mean age of the 15 elderly patients was 88.8 ± 5.4 years. All patients had at least three underlying diseases and catheters. Clinical outcomes improved in 10 of the 15 patients after antibiotic and/or mechanical ventilation treatment, but three patients had chronic infections lasting more than 1 year. The mortality rate was 33.3% (5/15). All strains were resistant to aminoglycosides, aztreonam, nitrofurantoin, and third- and fourth-generation cephalosporins (except ceftazidime and cefoperazone). Six new STs were detected. The most frequent ST was ST306. ST5 was identified in two separate buildings of the hospital. ST313 showed higher MIC in cephalosporins, quinolones and carbapenems, which should be more closely considered in clinical practice. All strains produced biofilm and had integron I and blaOXA-114-like . The main type was blaOXA-114q . The variable region of integron I was different among strains, and the resistance gene of the aminoglycosides was most commonly inserted in integron I. Additionally, blaPSE-1 was first reported in this isolate. CONCLUSION Achromobacter spp. infection often occurs in severely ill elders with underlying diseases. The variable region of integrons differs, suggesting that Achromobacter spp. is a reservoir of various resistance genes.
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Affiliation(s)
- Chao Liu
- Intensive Care Unit, Beijing Haidian Hospital, Haidian Section of Peking University Third HospitalBeijing, China
| | - Fei Pan
- Department of Gastroenterology and Hepatology, Chinese PLA General HospitalBeijing, China
| | - Jun Guo
- Department of Respiratory Medicine, Beijing Tsinghua Changgung Hospital, Medical Center, Tsinghua UniversityBeijing, China
| | - Weifeng Yan
- Intensive Care Unit, Beijing Haidian Hospital, Haidian Section of Peking University Third HospitalBeijing, China
| | - Yi Jin
- Intensive Care Unit, Beijing Haidian Hospital, Haidian Section of Peking University Third HospitalBeijing, China
| | - Changting Liu
- Nanlou Respiratory, Diseases Department, Chinese PLA General HospitalBeijing, China
| | - Long Qin
- Intensive Care Unit, Beijing Haidian Hospital, Haidian Section of Peking University Third HospitalBeijing, China
| | - Xiangqun Fang
- Nanlou Respiratory, Diseases Department, Chinese PLA General HospitalBeijing, China
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Isolation and molecular characterisation of Achromobacter phage phiAxp-3, an N4-like bacteriophage. Sci Rep 2016; 6:24776. [PMID: 27094846 PMCID: PMC4837373 DOI: 10.1038/srep24776] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 04/05/2016] [Indexed: 02/07/2023] Open
Abstract
Achromobacter xylosoxidans, an opportunistic pathogen, is responsible for various nosocomial and community-acquired infections. We isolated phiAxp-3, an N4-like bacteriophage that infects A. xylosoxidans, from hospital waste and studied its genomic and biological properties. Transmission electron microscopy revealed that, with a 67-nm diameter icosahedral head and a 20-nm non-contractile tail, phiAxp-3 has features characteristic of Podoviridae bacteriophages (order Caudovirales). With a burst size of 9000 plaque-forming units and a latent period of 80 min, phiAxp-3 had a host range limited to only four A. xylosoxidans strains of the 35 strains that were tested. The 72,825 bp phiAxp-3 DNA genome, with 416-bp terminal redundant ends, contains 80 predicted open reading frames, none of which are related to virulence or drug resistance. Genome sequence comparisons place phiAxp-3 more closely with JWAlpha and JWDelta Achromobacter phages than with other N4 viruses. Using proteomics, we identified 25 viral proteins from purified phiAxp-3 particles. Notably, investigation of the phage phiAxp-3 receptor on the surface of the host cell revealed that lipopolysaccharide serves as the receptor for the adsorption of phage phiAxp-3. Our findings advance current knowledge about A. xylosoxidans phages in an age where alternative therapies to combat antibiotic-resistant bacteria are urgently needed.
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Firmida MC, Pereira RHV, Silva EASR, Marques EA, Lopes AJ. Clinical impact of Achromobacter xylosoxidans colonization/infection in patients with cystic fibrosis. Braz J Med Biol Res 2016; 49:e5097. [PMID: 26909788 PMCID: PMC4792508 DOI: 10.1590/1414-431x20155097] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 12/17/2015] [Indexed: 12/20/2022] Open
Abstract
The rate of diagnosis of colonization/infection of the airways with
Achromobacter xylosoxidans has increased in cystic fibrosis
patients, but its clinical significance is still controversial. This retrospective,
case-control study aimed to evaluate the clinical impact of A.
xylosoxidans colonization/infection in cystic fibrosis patients.
Individuals who were chronically colonized/infected (n=10), intermittently
colonized/infected (n=15), and never colonized/infected with A.
xylosoxidans (n=18) were retrospectively evaluated during two
periods that were 2 years apart. Demographic characteristics, clinical data, lung
function, and chronic bacterial co-colonization data were evaluated. Of the total
study population, 87% were pediatric patients and 65.1% were female. Individuals
chronically colonized/infected with A. xylosoxidans had decreased
forced expiratory volume in 1 s (51.7% in the chronic colonization/infection group
vs 82.7% in the intermittent colonization/infection group
vs 76% in the never colonized/infected group). Compared with the
other two groups, the rate of co-colonization with methicillin-resistant
Staphylococcus aureus was higher in individuals chronically
colonized/infected with A. xylosoxidans (P=0.002).
Changes in lung function over 2 years in the three groups were not significant,
although a trend toward a greater decrease in lung function was observed in the
chronically colonized/infected group. Compared with the other two groups, there was a
greater number of annual hospitalizations in patients chronically colonized/infected
with A. xylosoxidans (P=0.033). In cystic fibrosis patients, there
was an increased frequency of A. xylosoxidans colonization/infection
in children, and lung function was reduced in patients who were chronically
colonized/infected with A. xylosoxidans. Additionally, there were no
differences in clinical outcomes during the 2-year period, except for an increased
number of hospitalizations in patients with A. xylosoxidans.
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Affiliation(s)
- M C Firmida
- Programa de Pós-Graduação em Ciências Médicas, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - R H V Pereira
- Departamento de Microbiologia, Imunologia e Parasitologia, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - E A S R Silva
- Laboratório de Bacteriologia, Hospital Universitário Pedro Ernesto, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - E A Marques
- Programa de Pós-Graduação em Ciências Médicas, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - A J Lopes
- Programa de Pós-Graduação em Ciências Médicas, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
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