Assuntos
Antibacterianos , Enterobacteriáceas Resistentes a Carbapenêmicos , Carbapenêmicos , Infecções por Klebsiella , Klebsiella pneumoniae , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , Klebsiella pneumoniae/genética , Infecções por Klebsiella/microbiologia , Infecções por Klebsiella/tratamento farmacológico , Animais , Carbapenêmicos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Djibuti/epidemiologia , Peixes/microbiologia , Testes de Sensibilidade Microbiana , Virulência , Doenças dos Peixes/microbiologiaRESUMO
Achromobacter spp. are nonfermentative Gram-negative bacilli considered emergent pathogens in cystic fibrosis (CF). Although some cross-transmission events between CF patients have been described, Achromobacter strains were mostly patient specific, suggesting sporadic acquisitions from nonhuman reservoirs. However, sources of these emergent CF pathogens remain unknown. A large collection of specimens (n = 273) was sampled in the homes of 3 CF patients chronically colonized by Achromobacter xylosoxidans with the aim of evaluating the potential role of domestic reservoirs in sustaining airway colonization of the patients. Samples were screened for the presence of Achromobacter by using genus-specific molecular detection. Species identification, multilocus genotypes, and antimicrobial susceptibility patterns observed for environmental isolates were compared with those of clinical strains. Patient homes hosted a high diversity of Achromobacter species (n = 7), including Achromobacter mucicolens and A. animicus, two species previously isolated from human samples only, and genotypes (n = 15), all showing an overall susceptibility to antimicrobial agents. Achromobacter strains were mostly isolated from indoor moist environments and siphons, which are potential reservoirs for several CF emerging pathogens. A. xylosoxidans, the worldwide prevalent species colonizing CF patients, was not the major Achromobacter species inhabiting domestic environments. A. xylosoxidans genotypes chronically colonizing the patients were not detected in their household environments. These results support the notions that the domestic environment could not be incriminated in sustained patient colonization and that after initial colonization, the environmental survival of A. xylosoxidans clones adapted to the CF airways is probably impaired.IMPORTANCEAchromobacter spp. are worldwide emerging opportunistic pathogens in CF patients, able to chronically colonize the respiratory tract. Apart from regular consultations at the hospital CF center, patients spend most of their time at home. Colonization from nonhuman sources has been suggested, but the presence of Achromobacter spp. in CF patients' homes has not been explored. The domestic environments of CF patients chronically colonized by Achromobacter, especially wet environments, host several opportunistic pathogens, including a large diversity of Achromobacter species and genotypes. However, Achromobacter genotypes colonizing the patients were not detected in their domestic environments, making it unlikely that a shuttle between environment and CF airways is involved in persisting colonization. This also suggests that once the bacteria have adapted to the respiratory tract, their survival in the domestic environment is presumably impaired. Nevertheless, measures for reducing domestic patient exposure should be targeted on evacuation drains, which are frequently contaminated by CF opportunistic pathogens.
Assuntos
Achromobacter denitrificans/crescimento & desenvolvimento , Fibrose Cística/microbiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Achromobacter denitrificans/genética , Achromobacter denitrificans/isolamento & purificação , Adolescente , Adulto , Genótipo , Humanos , Masculino , Sistema Respiratório/microbiologia , Adulto JovemRESUMO
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.
Assuntos
Achromobacter/classificação , Achromobacter/efeitos dos fármacos , Fibrose Cística/complicações , Farmacorresistência Bacteriana , Variação Genética , Infecções por Bactérias Gram-Negativas/microbiologia , Escarro/microbiologia , Achromobacter/genética , Achromobacter/isolamento & purificação , Adolescente , Adulto , Criança , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Eletroforese em Gel de Campo Pulsado , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Adulto JovemRESUMO
The genetic structures involved in the dissemination of blaCMY-2 carried by Proteus mirabilis isolates recovered from different gull species in the South of France were characterized and compared to clinical isolates. blaCMY-2 was identified in P. mirabilis isolates from 27/93 yellow-legged gulls and from 37/65 slender-billed gulls. It was carried by a conjugative SXT/R391-like integrative and conjugative element (ICE) in all avian strains and in 3/7 human strains. Two clinical isolates had the same genetic background as six avian isolates.
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Charadriiformes/microbiologia , Conjugação Genética , Proteus mirabilis/genética , beta-Lactamases/genética , Animais , Mapeamento Cromossômico , Cromossomos Bacterianos , Fezes/microbiologia , França , Humanos , Prevalência , Proteus mirabilis/isolamento & purificaçãoRESUMO
Dental care unit waterlines (DCUWs) consist of complex networks of thin tubes that facilitate the formation of microbial biofilms. Due to the predilection toward a wet environment, strong adhesion, biofilm formation, and resistance to biocides, Pseudomonas aeruginosa, a major human opportunistic pathogen, is adapted to DCUW colonization. Other nonfermentative Gram-negative bacilli, such as members of the genus Achromobacter, are emerging pathogens found in water networks. We reported the 6.5-year dynamics of bacterial contamination of waterlines in a dental health care center with 61 dental care units (DCUs) connected to the same water supply system. The conditions allowed the selection and the emergence of clones of Achromobacter sp. and P. aeruginosa characterized by multilocus sequence typing, multiplex repetitive elements-based PCR, and restriction fragment length polymorphism in pulsed-field gel electrophoresis, biofilm formation, and antimicrobial susceptibility. One clone of P. aeruginosa and 2 clones of Achromobacter sp. colonized successively all of the DCUWs: the last colonization by P. aeruginosa ST309 led to the closing of the dental care center. Successive dominance of species and clones was linked to biocide treatments. Achromobacter strains were weak biofilm producers compared to P. aeruginosa ST309, but the coculture of P. aeruginosa and Achromobacter enhanced P. aeruginosa ST309 biofilm formation. Intraclonal genomic microevolution was observed in the isolates of P. aeruginosa ST309 collected chronologically and in Achromobacter sp. clone A. The contamination control was achieved by a complete reorganization of the dental health care center by removing the connecting tubes between DCUs.
Assuntos
Achromobacter/crescimento & desenvolvimento , Achromobacter/isolamento & purificação , Consultórios Odontológicos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/isolamento & purificação , Microbiologia da Água , Achromobacter/classificação , Achromobacter/genética , Impressões Digitais de DNA , Eletroforese em Gel de Campo Pulsado , Evolução Molecular , Humanos , Dados de Sequência Molecular , Tipagem de Sequências Multilocus , Polimorfismo de Fragmento de Restrição , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/genética , Análise de Sequência de DNAAssuntos
Monofosfato de Adenosina/análogos & derivados , Aneurisma Intracraniano/cirurgia , Trombose Intracraniana/prevenção & controle , Inibidores da Agregação Plaquetária/uso terapêutico , Stents , Monofosfato de Adenosina/uso terapêutico , Aspirina/uso terapêutico , Encéfalo/cirurgia , Feminino , Fibrinolíticos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
BACKGROUND: Radiopharmaceuticals preparation unit, such as every aseptic preparation units, are strictly monitored in terms of microbiological contamination. Despite all biocontamination control procedures, our radiopharmacy unit faced repeated environmental contamination by Achromobacter spp which necessitated a large environmental investigation. METHODS: Microbiological controls were carried out using Count Tact agars (Biomérieux) for flat surfaces, dry swabbing for hard to reach areas and containers were filled with a sterile water solution (then filtrated on 0.45 µm membrane and seeded). Microbiological identification was performed by mass spectrometry (MALDI-TOF-MS, Brucker) on each positive sample. RESULTS: Achromobacter spp was found in 10% of the 413 samples during the 8 months investigation period. The proportion of positive samples was stable among time but their location was unpredictable. The highest inoculum was finally found in the buckets used for biocleaning. DISCUSSION: Samples from cleaning buckets taken by dry swabbing were at first negative, but the use of a non-routinely used sampling method allowed to discover the reservoir of this persistent contamination. CONCLUSION: This investigation alerted us on the high microbiological risk associated with reusable plastic containers and the importance of a sampling method adapted to critical locations.
Assuntos
Achromobacter , Humanos , Poluição AmbientalRESUMO
In cystic fibrosis (CF), Pseudomonas aeruginosa (Pa) is a major pathogen that can persistently colonize patients. Genetic studies showed a high diversity of Pa, the success of widespread or 'international' clones and described epidemic clones in CF and Epidemic High-Risk (ERH) clones. Here, we characterized Pa genetic diversity over time after first colonization in CF patients, with the aim of accurately describing the dynamics of colonization in a context of scarce longitudinal studies including the first isolated Pa strain. Results represent the first genotyping data available for CF Pa in France. Forty-four CF patients with a first Pa colonization were included; 265 strains collected over 7 years in these patients were genotyped by multiplex rep-PCR, multilocus sequence typing, pulsed-field gel electrophoresis and/or whole genome sequencing. Forty-one sequence types were identified: 4 were unknown, 22 never previously reported for CF patients, and 6 corresponded to widespread clones colonizing 16 patients (36%). Unrelated strains were identified in 41 patients (93%). Twenty-six patients (59%) presented a recurrence during the study period. No specific clones were associated with transient, recurrent or persistent colonization. Our longitudinal study revealed that 9 of the 26 patients with recurrence (35%) harbored strains of different genotypes. Great genetic diversity was observed among initial Pa isolates excluding any cross-transmission. Persistent colonization may appear more complex than expected, imitating persistence, with successive colonization events by unrelated Pa.
Assuntos
Fibrose Cística , Infecções por Pseudomonas , Humanos , Fibrose Cística/complicações , Pseudomonas aeruginosa/genética , Infecções por Pseudomonas/epidemiologia , Infecções por Pseudomonas/diagnóstico , Estudos Longitudinais , Variação GenéticaRESUMO
The emergence of carbapenem resistance is a major public health threat in sub-Saharan Africa but remains poorly understood, particularly at the human-animal-environment interface. This study provides the first One Health-based study on the epidemiology of Carbapenemase-Producing Gram-Negative Bacteria (CP-GNB) in Djibouti City, Djibouti, East Africa. In total, 800 community urine samples and 500 hospital specimens from humans, 270 livestock fecal samples, 60 fish samples, and 20 water samples were collected and tested for carbapenem resistance. The overall estimated CP-GNB prevalence was 1.9 % (32/1650 samples) and specifically concerned 0.3 % of community urine samples, 2.8 % of clinical specimens, 2.6 % of livestock fecal samples, 11.7 % of fish samples, and 10 % of water samples. The 32 CP-GNB included 19 Escherichia coli, seven Acinetobacter baumannii, five Klebsiella pneumoniae, and one Proteus mirabilis isolate. Short-read (Illumina) and long-read (Nanopore) genome sequencing revealed that carbapenem resistance was mainly associated with chromosomal carriage of blaNDM-1, blaOXA-23, blaOXA-48, blaOXA-66, and blaOXA-69 in A. baumannii, and with plasmid carriage in Enterobacterales (blaNDM-1 and blaOXA-181 in E. coli, blaNDM-1, blaNDM-5 and blaOXA-48 in K. pneumoniae, and blaNDM-1 in P. mirabilis). Moreover, 17/32 CP-GNB isolates belonged to three epidemic clones: (1) A. baumannii sequence type (ST) 1697,2535 that showed a distribution pattern consistent with intra- and inter-hospital dissemination; (2) E. coli ST10 that circulated at the human-animal-environment interface; and (3) K. pneumoniae ST147 that circulated at the human-environment interface. Horizontal exchanges probably contributed to carbapenem resistance dissemination in the city, especially the blaOXA-181-carrying ColKP3-IncX3 hybrid plasmid that was found in E. coli isolates belonging to different STs. Our study highlights that despite a relatively low CP-GNB prevalence in Djibouti City, plasmids harboring carbapenem resistance circulate in humans, animals and environment. Our findings stress the need to implement preventive and control measures for reducing the circulation of this potentially emerging public health threat.
Assuntos
Proteínas de Bactérias , Escherichia coli , Humanos , Animais , Escherichia coli/genética , Djibuti/epidemiologia , Proteínas de Bactérias/genética , beta-Lactamases/genética , Plasmídeos , Klebsiella pneumoniae , Carbapenêmicos , Genômica , Água , Antibacterianos/farmacologia , Testes de Sensibilidade MicrobianaRESUMO
Mycobacterium bovis infects cattle and wildlife, and also causes a small proportion of tuberculosis cases in humans. In most European countries, M. bovis infections in cattle have been drastically reduced, but not eradicated. Here, to determine the M. bovis circulation within and between the human, cattle, and wildlife compartments, we characterized by spoligotyping and mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) typing the genetic diversity of M. bovis isolates collected from humans, cattle, and wildlife in France from 2000 to 2010. We also assessed their genetic structure within and among the different host groups, and across time and space. The M. bovis genetic structure and its spatiotemporal variations showed different dynamics in the human and animal compartments. Most genotypes detected in human isolates were absent in cattle and wildlife isolates, possibly because in patients, M. bovis infection was contracted abroad or was the reactivation of an old lesion. Therefore, they did not match the genetic pool present in France during the study period. However, some human-cattle exchanges occurred because some genotypes were common to both compartments. This study provides new elements for understanding M. bovis epidemiology in France, and calls for increased efforts to control this pathogen worldwide.
RESUMO
INTRODUCTION: To date, corticosteroids remain the cornerstone treatment of ocular involvement of GCA, and no other treatment has proven to be effective in this setting. We herein report on a unique case of GCA with ocular involvement worsening despite high dose corticosteroids and recovering with intravenous iloprost. CASE REPORT: A 70-year-old man presented with acute vision loss in his left eye related to anterior ischemic optic neuropathy. The diagnosis of giant-cell arteritis was confirmed by a temporal artery biopsy. Despite intravenous pulse methylprednisolone for 3 days then oral prednisone at 60 mg/day, the patient developed from day 5 fluctuating vision loss in the right eye, related to ocular ischemia by occlusion of the ophthalmic artery, and responsive to hyperhydration. Iloprost, an analog of prostacyclin PGI2, was then administered intravenously for 5 days and resulted in a stable improvement in visual acuity in the right eye. CONCLUSION: This case highlights the potential role of vasodilatator agents in giant cell arteritis with ocular involvement.
Assuntos
Arterite de Células Gigantes , Neuropatia Óptica Isquêmica , Corticosteroides/uso terapêutico , Idoso , Arterite de Células Gigantes/diagnóstico , Arterite de Células Gigantes/tratamento farmacológico , Humanos , Iloprosta/uso terapêutico , Masculino , Neuropatia Óptica Isquêmica/diagnóstico , Neuropatia Óptica Isquêmica/tratamento farmacológico , Neuropatia Óptica Isquêmica/etiologia , Artérias Temporais/patologiaRESUMO
Non-tuberculous mycobacteria (NTM) are opportunistic pathogens commonly colonizing hospital water systems, and may be responsible for healthcare-associated infections (HAI). Investigation of HAI and outbreaks caused by NTM necessitates water analyses. However, NTM are slow-growing bacteria within the mesophilic community present in water, and are difficult to detect. Prior to culture on specific media, their recovery usually requires decontamination and concentration steps. We assessed the effectiveness of filtration as regards the recovery of 7 NTM species in hospital water samples. We also compared the use of cetylpyridinium chloride (CPC) at different concentrations and Sodium Hydroxide (NaOH) 4% in decontamination of water samples with mesophilic bacteria. Our laboratory protocol showed that membrane filtration was suitable for concentration and recovery of NTM from water. Sample decontamination with CPC was more NTM-preservative than NaOH. A combination of CPC at 0.005% and filtration allowed detection of NTM at low concentrations, ranging from 3 to 98 CFU/100mL according to the NTM species.
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Cetilpiridínio , Micobactérias não Tuberculosas , Meios de Cultura , Hospitais , ÁguaRESUMO
In patients with cystic fibrosis (CF), the lung is a remarkable ecological niche in which the microbiome is subjected to important selective pressures. An inexorable colonization by bacteria of both endogenous and environmental origin is observed in most patients, leading to a vicious cycle of infection-inflammation. In this context, long-term colonization together with competitive interactions among bacteria can lead to over-inflammation. While Pseudomonas aeruginosa and Staphylococcus aureus, the two pathogens most frequently identified in CF, have been largely studied for adaptation to the CF lung, in the last few years, there has been a growing interest in emerging pathogens of environmental origin, namely Achromobacter xylosoxidans and Stenotrophomonas maltophilia. The aim of this review is to gather all the current knowledge on the major pathophysiological traits, their supporting mechanisms, regulation and evolutionary modifications involved in colonization, virulence, and competitive interactions with other members of the lung microbiota for these emerging pathogens, with all these mechanisms being major drivers of persistence in the CF lung. Currently available research on A. xylosoxidans complex and S. maltophilia shows that these emerging pathogens share important pathophysiological features with well-known CF pathogens, making them important members of the complex bacterial community living in the CF lung.
Assuntos
Achromobacter denitrificans/genética , Fibrose Cística/microbiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Taxa de Mutação , Stenotrophomonas maltophilia/genética , Achromobacter denitrificans/patogenicidade , Adaptação Fisiológica , Fibrose Cística/complicações , Infecções por Bactérias Gram-Negativas/complicações , Humanos , Pulmão/microbiologia , Stenotrophomonas maltophilia/patogenicidadeRESUMO
Cystic Fibrosis (CF) airways favor abnormal microbial development. Infections are considered as polymicrobial and competition can be observed between microorganisms. The current literature on bacterial competition in CF mostly consists of studies with limited numbers of strains, mainly focused on the major pathogens Pseudomonas aeruginosa (Pa) and Staphylococcus aureus (Sa) and does not give a comprehensive overview of the overall importance of bacterial interactions or the behavior of less often encountered emerging bacteria such as Achromobacter. In this context, we screened a panel of 39 strains from six CF patients, of either clinical or domestic environmental origin, distinguished according to genotype and belonging to four opportunistic pathogens, Pa (n = 15), Sa (n = 3), Stenotrophomonas maltophilia (Sm, n = 10) and Achromobacter xylosoxidans (Ax, n = 11). We investigated their capacity to compete in terms of growth, motility, and pigment production on agar media through 203 crossing experiments. Eleven strains selected via the initial screening results were further studied for competitive growth in liquid medium and biofilm formation. Competition was noted for 33% (67/203) of the pairs of strains with 85 modifications observed between monocultures and co-cultures, impacting growth (23.6%), motility (13.8%), and/or pigment production (6.1%). Under all conditions of the study (clinical, environmental strains; intra-, inter-patients; intra-, inter-species levels), competition was significantly more frequent among pairs of strains with at least one clinical strain. While Pa mainly outcompeted other species, in one patient with chronic colonization by Ax and sporadic colonization by Pa, we showed that some Ax inhibited the growth and pigmentation of Pa whereas biofilm formation was drastically reduced. Enlarging the panel of strains tested in competition assays gave new perspectives on the complex interactions taking place among the CF airway community. Indeed, the frequent occurrence of varied, strain-dependent interactions is revealed here. We report the first results of competition assays for Ax with the ability of certain strains to outcompete Pa. Our results are linked to the patient's colonization history and question the importance of bacterial competitiveness in the colonization pattern of CF airways.
RESUMO
Among the complex microbial community living in the mosquito midgut, some bacteria (e.g., Enterobacter spp.) can deliver effector molecules with anti-Plasmodium effects suppressing the development of malaria parasites (Plasmodium falciparum) before the öokinete can penetrate the mosquito midgut epithelium. Despite knowledge of this phenomenon, only a few studies have defined the diversity of microbiota in wild-caught adult Anopheles species. The objective of this study was to analyze and compare the bacterial microbiota in different Anopheles species, including representatives of the primary malaria vectors in western Thailand. Wild female Anopheles species were sampled from malaria-endemic areas in Tak and Mae Hong Son provinces near the Thai-Myanmar border. Midgut/abdominal bacterial diversity was assessed by examining the 16S rRNA gene, V3 hypervariable region, using PCR-Temporal Temperature Gel Electrophoresis (PCR-TTGE) profiling and sequence analysis. A total of 24 bacterial genera were identified from eight Anopheles species. Five bacterial genera were newly reported in Anopheles mosquitoes (Ferrimonas, Megasphaera, Pectobacterium, Shimwellia, and Trabulsiella). Five genera, including Megasphaera, were detected exclusively in a single-malaria (Plasmodium vivax) infected Anopheles minimus and not observed in other non-infected mosquitoes. The use of PCR-TTGE provides the first characterization of the midgut bacterial microbiome present in wild adult Anopheles in Thailand. Evidence that microbiota might impact pathogen development (suppression) in Anopheles and thereby reduce the risk of pathogen transmission deserves more studies to describe the presence and better understand the biological role of bacteria in natural mosquito populations.
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The pathogenic power of Streptococcus pseudopneumoniae has been specified over years, particularly in case of chronic respiratory diseases; S. pseudopneumoniae isolation has however not been characterized before in CF patients. Identification of S. pseudopneumoniae remains challenging due to the high simila-rity level between species of the Streptococcus mitis group. Twenty CF patients with S. pseudopneumoniae were included. Isolates initially identified by phenotypic routine methods were subjected to both recA sequencing and amplification of S. pseudopneumoniae specific markers. Microbiological and clinical data were reviewed for patients with confirmed S. pseudopneumoniae. Thirteen isolates actually belong to S. pseudopneumoniae. S. pseudopneumoniae was associated with pulmonary exacerbation in 46% of the patients, either as the sole pathogen or as part of a polymicrobial infectious process. S. pseudopneumoniae has to be considered as an additional opportunistic pathogen in CF and additional studies are needed to increase knowledge of its epidemiology and clinical significance in CF.
Assuntos
Antibacterianos/uso terapêutico , Fibrose Cística , Infecções Estreptocócicas , Streptococcus , Criança , Fibrose Cística/complicações , Fibrose Cística/microbiologia , Fibrose Cística/fisiopatologia , Fibrose Cística/terapia , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Técnicas Microbiológicas/métodos , Infecções Oportunistas/diagnóstico , Infecções Oportunistas/microbiologia , Sistema Respiratório/microbiologia , Sistema Respiratório/fisiopatologia , Análise de Sequência de DNA/métodos , Análise de Sequência de DNA/estatística & dados numéricos , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/microbiologia , Streptococcus/genética , Streptococcus/isolamento & purificação , Avaliação de SintomasRESUMO
Several environmental bacteria are considered as opportunistic pathogens in cystic fibrosis (CF) and are able to persistently colonize the CF respiratory tract (CFRT). Beside Pseudomonas aeruginosa and Burkholderia cepacia complex, Pandoraea spp. are defined as pathogenic. During chronic colonization, adaptive evolution and diversified population have been demonstrated, notably for P. aeruginosa. However, the persistence of Pandoraea in the CFRT remains largely unexplored. We studied genomic and phenotypic traits of Pandoraea pulmonicola isolates successively recovered from the airways of a single CF patient and relate the results to qualitative and quantitative evolution of other cultivable pathogens and to patient clinical status. A total of 31 isolates recovered from 18 sputum samples over a 7-year period in a single CF patient were studied. Genome dynamics was assessed by pulsed-field gel electrophoresis, ERIC-PCR fingerprinting and 16S rRNA gene PCR-temporal temperature gel electrophoresis. Phenotypic features included antimicrobial susceptibility, motility, biofilm production, and virulence in Caenorhabditis elegans model. Variability was observed for all the characteristics studied leading to highly diversified patterns (24 patterns) for the 31 clonally related isolates. Some of these modifications, mainly genomic events were concomitantly observed with CFRT microbiota composition shifts and with severe exacerbations. The diversity of P. pulmonicola population studied, observed for isolates recovered from successive samples but also within a sample suggested that existence of a diversified population may represent a patho-adaptive strategy for host persistence in the heterogeneous and fluctuating CFRT environment.