Molecular typing of Staphylococcus aureus bloodstream isolates from geriatric patients attending a long-term care Spanish hospital

Autor: M. Carmen Mendoza, Fernando Vázquez, M. Rosario Rodicio, Beatriz Guerra, M. Angeles Argudín
Rok vydání: 2011
Předmět:
Zdroj: Journal of Medical Microbiology. 60:172-179
ISSN: 1473-5644
0022-2615
DOI: 10.1099/jmm.0.021758-0
Popis: AllStaphylococcus aureusisolates (n=31) that caused bacteraemia in a Spanish geriatric hospital during 1996–2006 were analysed by a simple, rapid and inexpensive PCR technique based on variations in thehsdS1andhsdS2genes encoding the sequence recognition subunits of the Sau1 restriction–modification (RM) system. An equal number of isolates collected from surgical wounds over the same time period (control group) were similarly characterized. The RM test allocated 75 % of the isolates to the six major clonal complexes (CC1, CC5, CC8, CC22, CC30 and CC45) for which it was developed. However, recognition of minor CCs and precise identification of the circulating clones required more powerful and comprehensive techniques such asspatyping and multilocus sequence typing (MLST), which are more demanding and expensive. The RM test is not intended to replacespaor MLST typing, but may be of use when time, technical and/or financial resources are limited. Overall, nine and seven CCs were detected in bloodstream and wound isolates, respectively. In both groups, CC5 was the most frequent (35.5 % each), followed by CC45 or CC8 (22.6 and 32.3 % of bloodstream and wound isolates, respectively). The frequency of meticillin resistance was lower in bloodstream (16.1 %) than in wound (51.6 %) isolates (P=0.0025). Among the former, sequence type (ST) 5-staphylococcal cassette chromosomemec(SCCmec) II, ST5-SCCmecIV, ST45-SCCmecIV and ST125-SCCmecIV (now dominant in Spanish hospitals) clones were found. Among the wound isolates, nine meticillin-resistant clones were represented, with three of them (ST125-SCCmecIII, ST125-SCCmecV and ST14-SCCmecV) being newly described.
Databáze: OpenAIRE