RESUMO
BACKGROUND: Staphylococcus aureus is a leading cause of community-acquired infections and healthcare-associated infections. Epidemiological data are useful for understanding the dynamics of the diffusion of this pathogen, and to plan control activities and monitor their efficacy. METHODS: S. aureus isolates were collected in 13 public hospital laboratories of Emilia-Romagna (northern Italy region) during February-March 2009; phenotypic and molecular characterizations of these isolates were performed. RESULTS: The study sample included 267 isolates, 57 from blood, 81 from respiratory tract, and 129 from wounds; 106 (40%) were methicillin-resistant S. aureus (MRSA). MRSA showed a limited number of circulating clones with 2 predominant spa types--t008 and t041--accounting for 36% and 27% of MRSA isolates, respectively. The t041 type had a higher prevalence of antimicrobial resistance compared to other spa types and accounted for most of the retrieved hetero-vancomycin-intermediate S. aureus (h-VISA), while t008 was more frequently detected in non-hospital isolates. A higher degree of genetic diversity was observed in methicillin-susceptible S. aureus (MSSA), with no predominant clones and low prevalence of antimicrobial resistance. The occurrence of community-acquired MRSA infection appears to be rare in Emilia-Romagna. CONCLUSIONS: In contrast to previous studies reporting Italian data, t008 was the most frequent spa type among MRSA isolates in Emilia-Romagna. The prevalence of antimicrobial resistance of different MRSA spa types could influence their ability to cause infections with hospital onset. The presence of only 2 major MRSA clones circulating in Emilia-Romagna increases the chances that a regional strategy aimed at MRSA prevention will be effective.
Assuntos
Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla , Staphylococcus aureus Resistente à Meticilina/genética , Meticilina , Staphylococcus aureus/genética , Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana , Farmacorresistência Bacteriana Múltipla/genética , Genótipo , Humanos , Itália , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Proteínas de Ligação às Penicilinas , Fenótipo , Staphylococcus aureus/classificação , Staphylococcus aureus/isolamento & purificaçãoRESUMO
This study aimed to evaluate the accuracy of routine systems (Vitek2 cards AST-N022 and AST-N026; Kirby Bauer; Etest) for susceptibility testing of Pseudomonas aeruginosa to piperacillin and piperacillin-tazobactam. Vitek2 (card AST-N022) showed the worst performance; the other three methods (Vitek2 card AST-N026, Kirby-Bauer and E-test) performed comparably but never fulfilled the minimal standard proposed by FDA.
Assuntos
Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana/normas , Piperacilina/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Técnicas Bacteriológicas/métodos , Técnicas Bacteriológicas/normas , Humanos , Testes de Sensibilidade Microbiana/métodos , Ácido Penicilânico/análogos & derivados , Ácido Penicilânico/farmacologia , Combinação Piperacilina e Tazobactam , Valor Preditivo dos Testes , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/isolamento & purificaçãoAssuntos
Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/enzimologia , Enterobacteriaceae/genética , Genes Bacterianos , beta-Lactamases/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Enterobacteriaceae/classificação , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/epidemiologia , Escherichia coli/enzimologia , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Feminino , Humanos , Itália/epidemiologia , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Proteus mirabilis/enzimologia , Proteus mirabilis/genética , Proteus mirabilis/isolamento & purificação , Adulto JovemRESUMO
This study aims to evaluate the positive predictive value (PPV) and the negative predictive value (NPV) of Vitek2 in detecting extended-spectrum beta-lactamase (ESBL) phenotypes when compared to a manual confirmatory test as gold standard. A sample of Escherichia coli, Klebsiella spp and Proteus mirabilis isolates were collected by 5 laboratories in the Emilia-Romagna Region (Italy). Vitek2 appears to be an accurate tool to detect ESBL phenotypes of E. coli isolates; some concern remains about its performance with the other bacterial species, especially P. mirabilis.