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OBJECTIVE: To assess the residual risk of waterborne contamination by Pseudomonas aeruginosa from a water network colonized by a single genotype [sequence type (ST) 299] despite the presence of antimicrobial filters in a medical intensive care unit (ICU). METHODS: During the first 19-month period since the ICU opened, contamination of the water network was assessed monthly by collecting water upstream of the filters. Downstream water was also sampled to assess the efficiency of the filters. P. aeruginosa isolates from patients were collected and compared with the waterborne ST299 P. aeruginosa by multiplex-rep polymerase chain reaction (PCR), pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing. Cross-transmission events by other genotypes of P. aeruginosa were also assessed. RESULTS: Overall, 1.3% of 449 samples of filtered water were positive for P. aeruginosa in inoculum, varying between 1 and 104 colony-forming units/100 mL according to the tap. All P. aeruginosa hydric isolates belonged to ST299 and displayed fewer than two single nucleotide polymorphisms (SNPs). Among 278 clinical isolates from 122 patients, 10 isolates in five patients showed identical profiles to the hydric ST299 clone on both multiplex-rep PCR and PFGE, and differed by an average of fewer than five SNPs, confirming the water network reservoir as the source of contamination by P. aeruginosa for 4.09% of patients. Cross-transmission events by other genotypes of P. aeruginosa were responsible for the contamination of 1.75% of patients. DISCUSSION/CONCLUSION: Antimicrobial filters are not sufficient to protect patients from waterborne pathogens when the water network is highly contaminated. A microbiological survey of filtered water may be needed in units hosting patients at risk of P. aeruginosa infections, even when all water points-of-use are fitted with filters.
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Eletroforese em Gel de Campo Pulsado , Genótipo , Unidades de Terapia Intensiva , Infecções por Pseudomonas , Pseudomonas aeruginosa , Microbiologia da Água , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/isolamento & purificação , Pseudomonas aeruginosa/classificação , Humanos , Infecções por Pseudomonas/microbiologia , Infecções por Pseudomonas/transmissão , Filtração/instrumentação , Sequenciamento Completo do Genoma , Tipagem Molecular , Infecção Hospitalar/microbiologia , Infecção Hospitalar/prevenção & controle , Medição de RiscoRESUMO
Achromobacter spp. are opportunistic pathogens of environmental origin increasingly isolated in patients with underlying conditions like cystic fibrosis (CF). Despite recent advances, their virulence factors remain incompletely studied, and siderophore production has not yet been investigated in this genus. The aim of this study was to evaluate the production of siderophores in a large collection of Achromobacter spp. and evaluate the variability according to the origin of the strain and species. A total of 163 strains were studied, including 128 clinical strains (CF and non-CF patients) and 35 strains of environmental origin. Siderophores were quantified by the liquid chrome azurol-sulphonate assay. Species were identified by nrdA gene-based phylogeny. Strains were assigned to 20 species, with Achromobacter xylosoxidans being the most represented (51.5% of strains). Siderophore production was observed in 72.4% of the strains, with amounts ranging from 10.1% to 90% siderophore units. A significantly higher prevalence of siderophore-producing strains and greater production of siderophores were observed for clinical strains compared with strains of environmental origin. Highly variable observations were made according to species: A. xylosoxidans presented unique characteristics (one of the highest prevalence of producing strains and highest amounts produced, particularly by CF strains). Siderophores are important factors for bacterial growth commonly produced by members of the Achromobacter genus. The significance of the observations made during this study must be further investigated. Indeed, the differences observed according to species and the origin of strains suggest that siderophores may represent important determinants of the pathophysiology of Achromobacter spp. infections and also contribute to the particular epidemiological success of A. xylosoxidans in human infections. IMPORTANCE: Achromobacter spp. are recognized as emerging opportunistic pathogens in humans with various underlying diseases, including cystic fibrosis (CF). Although their pathophysiological traits are increasingly studied, their virulence factors remain incompletely described. Particularly, siderophores that represent important factors of bacterial growth have not yet been studied in this genus. A population-based study was performed to explore the ability of members of the Achromobacter genus to produce siderophores, both overall and in relevant subgroups (Achromobacter species; strain origin, either clinical-from CF or non-CF patients-or environmental). This study provides original data showing that siderophore production is a common trait of Achromobacter strains, particularly observed among clinical strains. The major species, Achromobacter xylosoxidans, encompassed both one of the highest prevalence of siderophore-producing strains and strains producing the largest amounts of siderophores, particularly observed for CF strains. These observations may represent additional advantages accounting for the epidemiological success of this species.
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Achromobacter denitrificans , Achromobacter , Fibrose Cística , Infecções por Bactérias Gram-Negativas , Humanos , Achromobacter/genética , Fibrose Cística/microbiologia , Prevalência , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Achromobacter denitrificans/genética , Fatores de Virulência/genética , SideróforosRESUMO
INTRODUCTION: Common major pathogens like Pseudomonas aeruginosa are identified in the airways of patients with cystic fibrosis (CF) and non-CF bronchiectasis. However, other opportunistic bacterial pathogens like Achromobacter xylosoxidans complex, Stenotrophomonas maltophilia and non-tuberculous mycobacteria are currently emerging in CF and are also reported in non-CF bronchiectasis. BACKGROUND: The emergence of opportunistic bacterial pathogens has been recognized in CF through annual national reports of sputum microbiology data. Despite common factors driving the emergence of bacteria identified in CF and non-CF bronchiectasis patients, bronchiectasis registries have been created more recently and no longitudinal analysis of recorded microbiological data is currently available in the literature, thereby preventing the recognition of emerging bacteria in patients with non-CF bronchiectasis. OUTLOOK: A longitudinal follow-up of microbiological data is still needed in non-CF bronchiectasis to identify emerging opportunistic bacterial pathogens. Homogeneity in practice of sputum microbiological examination is also required to allow comparative analysis of data in CF and non-CF bronchiectasis. CONCLUSION: Bacterial pathogens recognized as emerging in CF have to be more carefully monitored in non-CF bronchiectasis in view of their association with deterioration of the lung disease.
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Bronquiectasia/microbiologia , Fibrose Cística/microbiologia , Microbiologia/tendências , Fibrose Pulmonar/microbiologia , Infecções Respiratórias/microbiologia , Bronquiectasia/complicações , Bronquiectasia/epidemiologia , Bronquiectasia/terapia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/microbiologia , Doenças Transmissíveis Emergentes/terapia , Fibrose Cística/complicações , Fibrose Cística/epidemiologia , Fibrose Cística/terapia , Humanos , Técnicas Microbiológicas/estatística & dados numéricos , Técnicas Microbiológicas/tendências , Monitorização Fisiológica/métodos , Monitorização Fisiológica/normas , Monitorização Fisiológica/tendências , Infecções Oportunistas/epidemiologia , Infecções Oportunistas/microbiologia , Infecções Oportunistas/terapia , Fibrose Pulmonar/complicações , Fibrose Pulmonar/epidemiologia , Fibrose Pulmonar/terapia , Infecções Respiratórias/complicações , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/terapia , Escarro/microbiologiaRESUMO
BACKGROUND: Acute haematogenous bone and joint infections (AHBJI) represent a diagnostic and therapeutic emergency in children, with significant potential sequelae in the case of delayed treatment. Although historically the recommendations for treatment have been based on surgery and prolonged antibiotic therapy, recent studies have demonstrated that short-course antibiotic therapy is also effective. OBJECTIVES: We evaluated a short-term antibiotic protocol for both osteomyelitis and septic arthritis in a 6 year retrospective study at the University Hospital of Montpellier. METHODS: This protocol was based on an initial intravenous treatment with a re-evaluation after 48 h and an early switch to oral therapy in the case of a favourable clinical course for a minimum total duration of 15 days. Antibiotics were selected based on local microbiological epidemiology and systematically adapted to bacteriological results. RESULTS: One hundred and seventy-six cases of AHBJI were included, comprising 56 patients with osteomyelitis, 95 with septic arthritis and 25 who had both of these. The aetiological agent was identified in 42% of the cases, with the main pathogens being Staphylococcus aureus (39%) and Kingella kingae (27%). The mean intravenous treatment duration was 4 days, while the total treatment duration was 15 days. There were no treatment failures, mild sequelae occurred in 1% of the cases and the secondary surgical revision rate was 7%. CONCLUSIONS: The results of this study are comparable to those reported for evaluations of prolonged antibiotic therapy protocols, thus indicating that a common short-term antimicrobial therapy for the management of both osteomyelitis and septic arthritis (minimum of 15 days) is a viable option for treating AHBJI in children. Further prospective studies to confirm these findings are hence warranted.
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Antibacterianos/administração & dosagem , Artrite Infecciosa/tratamento farmacológico , Esquema de Medicação , Osteomielite/tratamento farmacológico , Administração Intravenosa , Artrite Infecciosa/microbiologia , Criança , Pré-Escolar , Feminino , Hospitais Universitários/estatística & dados numéricos , Humanos , Lactente , Masculino , Infecções por Neisseriaceae/tratamento farmacológico , Osteomielite/microbiologia , Estudos Prospectivos , Estudos Retrospectivos , Infecções Estafilocócicas/tratamento farmacológicoRESUMO
BACKGROUND: Water networks in hospitals are frequently contaminated by opportunistic premise plumbing pathogens (OPPPs) leading to installation of antimicrobial filters on water points-of-use (POU) in order to limit patients' exposure. AIM: To assess the spread of OPPPs through secondary water routes (outside the plumbing system) in an adult haematology unit in which 52 out of 73 water POU were high risk for patients and protected by antimicrobial filters. METHODS: An observational audit identified six secondary water routes for which bacteria tracking and typing were performed in 315 surface samplings. Bacterial isolates were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and compared to the infra-species level by multiplex repetitive element sequence-based polymerase chain reaction and/or by restriction fragment length polymorphism in pulse-field gel electrophoresis. FINDINGS: Pseudomonas aeruginosa and Stenotrophomonas maltophilia, as well as non-pathogenic OPPP indicators, were detected in water collected upstream of antimicrobial filters. P. aeruginosa was the sole OPPP retrieved from tested surfaces (5.1%). The same clone of P. aeruginosa spread from water source to dry surfaces in the same room and cross-contaminated two sinks in different rooms. Three clones of non-pathogenic OPPP indicators spread more widely in different rooms. CONCLUSION: A strategy based on filtration of most (but not all) water POU in a haematology unit could be sufficient to limit the spread of OPPPs to the environment, provided a functional mapping of 'high-risk' POU has been undertaken. The residual spread of OPPPs and OPPP indicators linked to non-filtered water POU argues for careful monitoring of non-filtered water use.
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Filtração , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/isolamento & purificação , Stenotrophomonas maltophilia/classificação , Stenotrophomonas maltophilia/isolamento & purificação , Microbiologia da Água , Técnicas de Genotipagem , Hospitais , Humanos , Reação em Cadeia da Polimerase , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
Most multidrug-resistant (MDR) and extensively drug-resistant (XDR) P. aeruginosa strains belonged to epidemic high-risk (EHR) clones that succeeded worldwide in the context of hospital outbreaks. In order to study the intraclonal diversity in EHR P. aeruginosa, we selected clinical and environmental strains of the EHR clone ST308 that caused outbreak clusters over five years in a hospital and then persisted in the hospital environment during four additional years, causing sporadic infections. Unexpectedly, resistance phenotype was very diverse within the population, independently of the origin (environmental or human) and the period of isolation (during or after outbreaks). Most MDR/XDR strains belonged to clusters in pulsed-field gel electrophoresis (PFGE) while singleton strains instead displayed susceptible or moderately resistant phenotypes. High diversity was observed for motility and biofilm formation without correlation with the origin and the period. Resistance to biocides was not linked to epidemic success or to environmental persistence. Finally, the EHR clone ST308 did not display common adaptive traits, nor traits related to an origin or a period of isolation in the hospital. The major character of this EHR clone ST308 is its intraclonal diversity that probably warrants its adaptation and persistence in hospital whatever the conditions and therefore its epidemic behaviour. This diversity could result from adaptive radiation with the evolution of multiple lineages that fill available niches within a complex ecosystem such as a hospital.
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Infecção Hospitalar/tratamento farmacológico , Surtos de Doenças , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Pseudomonas/epidemiologia , Pseudomonas aeruginosa , Antibacterianos/farmacologia , Biofilmes/crescimento & desenvolvimento , Infecção Hospitalar/microbiologia , Eletroforese em Gel de Campo Pulsado , Hospitais , Humanos , Testes de Sensibilidade Microbiana , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , SorotipagemRESUMO
Roseomonas spp. are increasingly involved in human infectious diseases. The environmental source for infection is generally admitted in published cases owing to the origin of most Roseomonas species and to their affiliation to the family Acetobacteraceae in Rhodospirillales, which mainly groups environmental bacteria. For a better delineation of Roseomonas habitat and infectious reservoir, we related phenotype, phylotype (16S rRNA gene), genomotype (pulsed-field gel electrophoresis) and origin of 33 strains isolated from humans, hospital environment and natural environment. Genetic and metagenomic databases were also surveyed. The population structure of the genus showed clades associated with humans, whereas others grouped environmental strains only. Roseomonas mucosa is the main human-associated species and the study supported the idea that opportunistic infections due to this species are related to the patient skin microbiota rather than to the environment. In contrast, some strains belonging to other species isolated from patients with cystic fibrosis were related to environmental clades, suggesting an exogenous source for patient colonization. Accurate knowledge about the reservoirs of opportunistic pathogens that have long been considered of environmental origin is still needed and would be helpful to improve infection control and epidemiological survey of emerging human pathogens.
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Infecções por Bactérias Gram-Negativas/microbiologia , Methylobacteriaceae , Microbiota , Infecções Oportunistas/microbiologia , Pele/microbiologia , Antibacterianos/farmacologia , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana , Microbiologia Ambiental , Genoma Bacteriano , Humanos , Metagenoma , Metagenômica/métodos , Methylobacteriaceae/classificação , Methylobacteriaceae/efeitos dos fármacos , Methylobacteriaceae/genética , Testes de Sensibilidade Microbiana , Filogenia , RNA Ribossômico 16S/genéticaRESUMO
The bacterial transfusion risk is currently the greatest infectious risk of blood transfusion. We report the case of a child with postchemotherapy febrile neutropenia who presented septic shock following platelet transfusion contaminated with Citrobacter koseri. The life-threatening development could have been avoided by strict compliance with good clinical practice. The stability of mortality rates due to adverse effects of bacterial proliferation during platelet transfusions in France since 1994 calls for optimization of all preventive measures throughout the transfusion chain and perfect knowledge of transfusion rules by medical staff and care givers.
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Infecções por Enterobacteriaceae/complicações , Infecções por Enterobacteriaceae/etiologia , Neutropenia Febril/terapia , Transfusão de Plaquetas/efeitos adversos , Choque Séptico/microbiologia , Antineoplásicos/efeitos adversos , Criança , Citrobacter koseri/isolamento & purificação , Neutropenia Febril/induzido quimicamente , Feminino , HumanosRESUMO
Clostridium difficile causes antibiotic-associated diarrhoea and pseudomembranous colitis. The main virulence factors of C. difficile are the toxins A (TcdA) and B (TcdB). A third toxin, called binary toxin (CDT), can be detected in 17% to 23% of strains, but its role in human disease has not been clearly defined. We report six independent cases of patients with diarrhoea suspected of having C. difficile infection due to strains from toxinotype XI/PCR ribotype 033 or 033-like, an unusual toxinotype/PCR ribotype positive for CDT but negative for TcdA and TcdB. Four patients were considered truly infected by clinicians and were specifically treated with oral metronidazole. One of the cases was identified during a prevalence study of A(-)B(-)CDT(+) strains. In this study, we screened a French collection of 220 nontoxigenic strains and found only one (0.5%) toxinotype XI/PCR ribotype 033 or 033-like strain. The description of such strains raises the question of the role of binary toxin as a virulence factor and could have implications for laboratory diagnostics that currently rarely include testing for binary toxin.
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Rhizobium pusense was recently described after isolation from the rhizosphere of chickpea. Multilocus sequence-based analysis of clinical isolates identified as Agrobacterium (Rhizobium) radiobacter demonstrated that R. pusense is the main human pathogen within Agrobacterium (Rhizobium) spp. Clinical microbiology of Agrobacterium (Rhizobium) should be considered in the light of recent taxonomic changes.
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Infecções por Bactérias Gram-Negativas/microbiologia , Rhizobium/classificação , Rhizobium/isolamento & purificação , Infecções por Bactérias Gram-Negativas/diagnóstico , HumanosRESUMO
The emergence of carbapenemase-producing Gram-negative bacilli is a worldwide problem. To date, no study has evaluated the prevalence of faecal carriage of carbapenemase-producing and carbapenem-resistant Gram-negative bacilli (CR GNB) in France. From 1 February to 30 April 2012, we conducted a prospective, multicentre study in three University Hospitals and four General Hospitals in the south of France. The carriage of carbapenemase-producing Enterobacteriaceae (CPE) and other CR GNB was screened by both cultivation on chromID® CARBA and chromID® OXA-48 media (bioMérieux) and molecular tools [multiplex polymerase chain reaction (PCR) and NucliSENS EasyQ® KPC (bioMérieux)]. The genetic relationship between isolates was assessed by rep-PCR (DiversiLab, bioMérieux) or multilocus sequence typing (MLST). The prevalences of CR GNB and carbapenemase-producing bacteria were 2.4 % (27/1,135) and 0.4 % (n = 5), respectively. Two strains corresponded to OXA-23-producing Acinetobacter baumannii and belonged to the widespread sequence type (ST) 2/international clone II, whereas one strain was an ST15 OXA-48-producing Klebsiella pneumoniae. Two OXA-48-producers were detected exclusively by PCR. This first French study revealed the very low dissemination of carbapenemase-producing bacteria in patients attending hospitals in southern France during a non-outbreak situation. However, the increasing description of epidemic cases in this area must reinforce the use of hygiene procedures to prevent diffusion of these multidrug-resistant microorganisms.
Assuntos
Proteínas de Bactérias/metabolismo , Portador Sadio/epidemiologia , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/epidemiologia , Hospitais Gerais , Hospitais Universitários , beta-Lactamases/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas Bacteriológicas , Portador Sadio/microbiologia , Criança , Pré-Escolar , Feminino , França/epidemiologia , Bactérias Gram-Negativas/enzimologia , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Adulto JovemRESUMO
BACKGROUND: Achromobacter spp. are Gram-negative bacilli from aqueous environments, occasionally involved in bacteraemia in immunocompromised hosts and in outbreaks. AIM: We describe the characteristics of an achromobacter bacteraemia outbreak in a paediatric onco-haematology department. METHODS: Throughout a one-year period, 16 blood cultures from seven patients were positive for Achromobacter sp. All patients were immunocompromised, febrile, and central venous catheter (CVC) holders. A microbiological study was performed in patients' rooms, completed with an analysis of the disinfectant atomizers (didecyl diammonium chloride 0.25%, Surfanios, DMA). In total, 41 clinical and environmental strains were analysed by enterobacterial repetitive intergenic consensus (ERIC) polymerase chain reaction (PCR), repetitive PCR, and random amplified polymorphic DNA (RAPD)-PCR, and pulsed-field gel electrophoresis (PFGE). The bactericidal activity of DMA was studied on two Achromobacter sp. representative strains and one Pseudomonas aeruginosa reference strain, comparing biofilm and planktonic growth models. FINDINGS: The seven patients, including two severe cases, were successfully treated by systemic antimicrobial therapy and/or catheter removal. The 25 environmental isolates were recovered with the following chronology: hospital filtered tap water, disinfectant atomizers, and patients' rooms. All environmental, patient, and atomizer strains had identical PCR and PFGE patterns. The disinfectant susceptibility assay revealed that the strain isolated from the atomizers had high survival abilities in biofilm conditions and remained resistant to DMA after short contact periods. CONCLUSION: The use of disinfectant atomizers associated with the survival of Achromobacter in the atomizer pipes may explain the contamination and colonization of the CVC. Control measures (non-atomizer containers and use of sterile water) allowed the eradication of the source and the outbreak control.
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Achromobacter/isolamento & purificação , Bacteriemia/microbiologia , Infecção Hospitalar/microbiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Neoplasias Hematológicas/microbiologia , Achromobacter/classificação , Adolescente , Anti-Infecciosos/uso terapêutico , Bacteriemia/sangue , Bacteriemia/tratamento farmacológico , Bacteriemia/epidemiologia , Infecções Relacionadas a Cateter/sangue , Infecções Relacionadas a Cateter/epidemiologia , Infecções Relacionadas a Cateter/microbiologia , Infecções Relacionadas a Cateter/terapia , Cateterismo Venoso Central/efeitos adversos , Criança , Pré-Escolar , Infecção Hospitalar/sangue , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/epidemiologia , Surtos de Doenças , Microbiologia Ambiental , França/epidemiologia , Infecções por Bactérias Gram-Negativas/sangue , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/epidemiologia , Neoplasias Hematológicas/sangue , Neoplasias Hematológicas/terapia , Humanos , Lactente , Masculino , Nebulizadores e Vaporizadores/microbiologia , Adulto JovemRESUMO
In February 2011, the CARB-LR group was created as a sentinel laboratory-based surveillance network to control the emergence of carbapenem-resistant Gram-negative bacilli (CR GNB) in a French Southern Region. We report the epidemiological results of a 2-year study. All the Gram-negative bacilli isolates detected in the different labs (hospital and community settings) of a French Southern Region and with reduced susceptibility to ertapenem and/or imipenem were characterised with regard to antibiotic resistance, bla genes content, repetitive sequence-based polymerase chain reaction (rep-PCR) profiles and multilocus sequence typing (MLST). A total of 221 strains were analysed. Acinetobacter baumannii was the most prevalent carbapenemase-producing bacteria, with a majority of OXA-23 producers (n = 37). One isolate co-produced OXA-23 and OXA-58 enzymes. Klebsiella pneumoniae was the most frequent carbapenemase-producing Enterobacteriaceae (CPE) (OXA-48 producer: n = 29, KPC producer: n = 1), followed by Escherichia coli (OXA-48 producer: n = 8, KPC producer: n = 1) and Enterobacter cloacae (OXA-48 producer, n = 1). One isolate of Pseudomonas aeruginosa produced a VIM-1 carbapenemase. A clonal diversity of carbapenemase-producing K. pneumoniae and E. coli was noted with different MLSTs. On the other hand, almost all OXA-23-producing A. baumannii strains belonged to the widespread ST2/international clone II. The link between the detection of CR GNB and a foreign country was less obvious, suggesting the beginning of a local cross-transmission. The number of CR GNB cases in our French Southern Region has sharply increased very recently due to the diffusion of OXA-48 producers.
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Proteínas de Bactérias/biossíntese , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/enzimologia , beta-Lactamases/biossíntese , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , França/epidemiologia , Humanos , Vigilância em Saúde PúblicaRESUMO
The prevalence of clonal complex (CC) 398 methicillin-susceptible Staphylococcus aureus (MSSA) was unexpectedly high among bone and joint infections (BJIs) and nasal-colonizing isolates in France, with surprising geographical heterogeneity. With none of the major, most-known staphylococcal virulence genes, MSSA CC398 BJI was associated with lower biological inflammatory syndrome and lower treatment failure rates.
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Artrite Infecciosa/microbiologia , Doenças Ósseas Infecciosas/microbiologia , Nariz/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/classificação , Staphylococcus aureus/isolamento & purificação , Adulto , Idoso , Artrite Infecciosa/epidemiologia , Doenças Ósseas Infecciosas/epidemiologia , Portador Sadio/microbiologia , Feminino , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Infecções Estafilocócicas/epidemiologiaRESUMO
The process of plate streaking has been automated to improve the culture readings, isolation quality, and workflow of microbiology laboratories. However, instruments have not been well evaluated under routine conditions. We aimed to evaluate the performance of the fully automated InoqulA instrument (BD Kiestra B.V., The Netherlands) in the automated seeding of liquid specimens and samples collected using swabs with transport medium. We compared manual and automated methods according to the (i) within-run reproducibility using Escherichia coli-calibrated suspensions, (ii) intersample contamination using a series of alternating sterile broths and broths with >10(5) CFU/ml of either E. coli or Proteus mirabilis, (iii) isolation quality with standardized mixed bacterial suspensions of diverse complexity and a 4-category standardized scale (very poor, poor, fair to good, or excellent), and (iv) agreement of the results obtained from 244 clinical specimens. By involving 15 technicians in the latter part of the comparative study, we estimated the variability in the culture quality at the level of the laboratory team. The instrument produced satisfactory reproducibility with no sample cross-contamination, and it performed better than the manual method, with more colony types recovered and isolated (up to 11% and 17%, respectively). Finally, we showed that the instrument did not shorten the seeding time over short periods of work compared to that for the manual method. Altogether, the instrument improved the quality and standardization of the isolation, thereby contributing to a better overall workflow, shortened the time to results, and provided more accurate results for polymicrobial specimens.
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Bactérias/isolamento & purificação , Técnicas Bacteriológicas/métodos , Manejo de Espécimes/métodos , Automação Laboratorial/métodos , Infecções Bacterianas/diagnóstico , Meios de Cultura , Humanos , Países Baixos , Reprodutibilidade dos TestesRESUMO
BACKGROUND: The source for late-onset neonatal infections (LONI) due to group B Streptococcus (GBS) has not been fully explored. We reviewed GBS LONI cases associated with contaminated breast milk to determine whether breast milk was a possible route for neonatal infection. DATA SOURCES: A PubMed search from January 1977 to March 2013 was performed with MeSH words "Streptococcus agalactiae", "group B Streptococcus", "infection", "milk", "human", "late-onset infection" and/or "neonate"; relevant cross references were also reviewed. RESULTS: Forty-eight documented cases of GBS LONI matched our search criteria and were retrieved from the literature. When performed, molecular typing identified clonal isolates in the neonate and milk samples taken after LONI in all cases, with the hypervirulent sequence type 17 (ST-17) clone identified in two of these cases. Caesarean delivery combined with the absence of GBS recovery from maternal samples other than milk was noted for four cases. The rate of recurrent infections was high (35%) and, together with the data reviewed, points to a potential role of breast milk in GBS LONI. CONCLUSIONS: The cases reviewed here, together with the evidence of breast milk transmission for other pathogens, suggest that breast milk, which would account for repeated GBS transmission to the neonate, may favour gut translocation and subsequent LONI. Further investigations are nevertheless needed to study the relative importance of this contamination route compared with persistent postnatal gut colonisation and the dynamics of milk and neonatal gut colonisation.
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Gastroenteropatias/microbiologia , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Leite Humano/microbiologia , Infecções Estreptocócicas/transmissão , Streptococcus agalactiae/isolamento & purificação , Feminino , Humanos , Recém-Nascido , Prevalência , Infecções Estreptocócicas/microbiologiaRESUMO
STUDY OBJECTIVE: To estimate the prevalence of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Mycoplasma genitalium (MG) in patients under 31 years of age admitted to the emergency department of the University Hospital of Montpellier, for which a urinalysis was performed. PATIENTS AND METHODS: CT, NG and MG specific real-time PCRs were performed in the urine samples from 301 patients between July 2010 and January 2011. RESULTS: CT DNA was detected in 11% of patients, NG DNA in 3.7% of patients and MG DNA in one patient. Seventy-five percent of male patients and only 13% of women were diagnosed with sexually transmitted infection (STI). No patient with leucocyturia below 10(4)/mL had a positive PCR result for one of the three bacteria. Of the patients with leucocyturia greater or equal to 10(4)/mL, CT was detected in 23.4% of men and 11% of women, NG in 19.2% of men and 1% of women, and MG in 2.1% of men. CONCLUSION: The prevalence of NG and CT detection in our population was high while that of MG was low. The diagnosis was facilitated by the use of PCR on the urine sample although this sample is not recommended for the molecular detection of bacterial agents of STIs and may explain the low detection of MG. The study allowed diagnosing STIs in 14.3% of our patient population.
Assuntos
Infecções por Chlamydia/epidemiologia , Chlamydia trachomatis , Gonorreia/epidemiologia , Infecções por Mycoplasma/epidemiologia , Mycoplasma genitalium , Neisseria gonorrhoeae , Adolescente , Adulto , Chlamydia trachomatis/isolamento & purificação , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , França/epidemiologia , Humanos , Masculino , Mycoplasma genitalium/isolamento & purificação , Neisseria gonorrhoeae/isolamento & purificação , Admissão do Paciente/estatística & dados numéricos , Prevalência , Adulto JovemRESUMO
We report retrospective analysis of the clinical and antimicrobial susceptibility data of 140 Streptococcus pseudopneumoniae isolates. Strains were isolated mostly from respiratory tract samples from patients with underlying diseases. In the case of infection, pneumonia, mainly aspiration pneumonia, was the most frequent (27.1% of the patients). We documented high rates of decreased susceptibilities and resistance to erythromycin and tetracycline (57% and 43% of the isolates, respectively), as well as reduced susceptibility to penicillin in 21% of the isolates.
Assuntos
Antibacterianos/farmacologia , Infecções Respiratórias/microbiologia , Infecções Estreptocócicas/microbiologia , Streptococcus/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Líquido da Lavagem Broncoalveolar/microbiologia , Criança , Eritromicina/farmacologia , Feminino , França , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Penicilinas/farmacologia , Pneumonia Bacteriana/microbiologia , Estudos Retrospectivos , Escarro/microbiologia , Streptococcus/isolamento & purificação , Tetraciclina/farmacologia , Adulto JovemRESUMO
Aeromonas species are environmental organisms that are responsible for numerous infections in humans and animals. Their antimicrobial susceptibility is usually evaluated using Enterobacteriaceae breakpoints. Although disk diffusion and minimum inhibitory concentration (MIC)-based methods are important for infectious disease management and epidemiological surveys of resistance, comparisons between these two methods have not been extensively studied for Aeromonas isolates. We propose the first extensive comparison of agar dilution and disk diffusion susceptibility testing methods, performed for 20 antimicrobial agents, including unevaluated or incompletely evaluated antibiotics (ticarcillin with or without clavulanic acid, ertapenem, tigecycline), on 146 Aeromonas isolates affiliated with six Aeromonas species via molecular means. We evaluated the level of agreement between Enterobacteriaceae breakpoints-based methods. Reliable agreement (>95%) was observed for piperacillin, cefotaxime, cefepime, nalidixic acid, ofloxacin, ciprofloxacin, gentamicin, amikacin, tetracycline and cotrimoxazole, whereas marked inconsistencies between the methods were noted for carbapenems, amoxicillin-clavulanic acid, ticarcillin, ticarcillin-clavulanic acid, tobramycin and tigecycline. The results indicate that beta-lactam and aminoglycoside susceptibility testing should be limited to piperacillin, cephems, gentamicin and amikacin. Co-amoxiclav should be avoided given the lack of agreement between the two methods. Adjusting the zone diameter breakpoints for tigecycline and cefoxitin could also improve the agreement to >95% and reduce the error rates to acceptable levels.
Assuntos
Aeromonas/efeitos dos fármacos , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana/métodos , Aeromonas/isolamento & purificação , Animais , Enterobacteriaceae/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/veterinária , HumanosRESUMO
16S rRNA gene-based cultivation-independent methods are increasingly used to study the diversity of microbiota during health and disease. One bias of these methods is the variability of 16S rRNA gene that may exist among strains of a same species (intraspecific heterogeneity) or between rrs copies in a genome (intragenomic heterogeneity). We evaluated the level of intraspecific and intragenomic 16S rDNA variability in seven species frequently encountered in respiratory tract samples in cystic fibrosis (CF). A total of 179 strains were subjected to V3 region 16S rDNA PCR-TTGE. Using this easy-to-perform and rapid method, different levels of V3 region rrs heterogeneity were demonstrated. No intraspecific and intragenomic rrs heterogeneity was demonstrated for Moraxella catarrhalis (n=16), Pseudomonas aeruginosa (n=31) and Streptococcus pneumoniae (n=14) showing a single PCR-TTGE band characteristic of the species. Low level of intraspecific heterogeneity was observed for Staphylococcus aureus (n=30), Stenotrophomonas maltophilia (n=29) and Achromobacter xylosoxidans (n=28), and 17%, 38% and 96% of these strains showed intragenomic heterogeneity (two to four different rrs copies), respectively. Haemophilus influenzae (n=31) displayed the higher level of intraspecific variability with 23 different PCR-TTGE patterns and 61% of the strains showed intragenomic rrs heterogeneity (two to four different rrs copies). Although only one hypervariable region of the 16S rRNA gene was explored, intraspecific and intragenomic rrs heterogeneity was frequently observed in this study and should be taken into consideration for a better interpretation of 16S rRNA gene-based diversity profiles in denaturing gels and to avoid any overestimation of the respiratory microbiota diversity in CF.