RESUMO
The aim of this study was to provide an overview of predominant and sporadic methicillin-resistant Staphylococcus aureus (MRSA) strains in large regions of Austria, and to compare the results with those from other European countries. In total, 1439 MRSA isolates, collected routinely between January 1996 and June 2006 from five Austrian federal provinces, were investigated. The isolates were confirmed as MRSA using mecA/femA multiplex PCR assays. Genes encoding Panton-Valentine leukocidin (PVL), which are characteristic of community-acquired MRSA, were also detected by PCR. Subtyping was performed using SmaI macrorestriction digestion of genomic DNA, followed by pulsed-field gel electrophoresis (PFGE) and cluster analysis. Isolates that could not be assigned to clusters were further analysed by spa typing and/or multilocus sequence typing. The predominant clones detected in Austria were ST228 (southern German epidemic clone), ST5 (Rhine-Hessen MRSA), the ST8 Austrian clone and CC8/ST8. Whereas the frequencies of lineages corresponding to ST247, ST45 and ST22 remained comparably low, an increase in the frequency of lineages corresponding to ST5 and to ST228 was recorded. Overall, 20 different MRSA types and 321 subtypes were recognised according to PFGE analysis. The prevalence of different strains varied considerably in the different Austrian regions. When compared to other European countries, the situation in Austria was most similar to that found in Germany.
Assuntos
Resistência a Meticilina , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/classificação , Staphylococcus aureus/efeitos dos fármacos , Antígenos de Bactérias/genética , Áustria/epidemiologia , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Técnicas de Tipagem Bacteriana , Análise por Conglomerados , Impressões Digitais de DNA , DNA Bacteriano/genética , Eletroforese em Gel de Campo Pulsado , Exotoxinas/genética , Genótipo , Leucocidinas/genética , Epidemiologia Molecular , Proteínas de Ligação às Penicilinas , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Prevalência , Análise de Sequência de DNA , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificaçãoRESUMO
The objective of this study was to present, for the first time, an overview of the existing Panton-Valentine leukocidin (PVL)-positive methicillin-resistant Staphylococcus aureus (MRSA) strains in Austria and to compare the situation with that found in other countries. Between 2001 and 2006 we analysed 1150 MRSA isolates - from infections as well as from colonisation - for the presence of PVL genes. The most common multilocus sequence types of the 94 PVL-positive MRSA strains were ST8, ST152, ST30, ST80, and ST5; the ST22, and ST777 sequences were also detected. During 2005 and 2006, 3.7-7.7% of the isolates were PVL-positive. The age distribution of the patients revealed that nosocomial MRSA mainly occurs in elderly people, whereas PVL-positive MRSA mainly appears in younger people. We observed a relatively high prevalence of PVL-positive isolates. Several MRSA clones containing the PVL genes are spreading throughout Austria, including two strains not yet widespread in Western Europe.
