Molecular epidemiology of methicillin resistant Staphylococcus aureus bacteremia in a teaching hospital from Argentina

DI GREGORIO S; GULONE L; PERAZZI B; ORDOÑEZ MARTINEZ A; MOLLERACH M; FAMIGLIETTI A

Congreso; International Congress of Traslational Medicine. Cellular and Molecular Pathways as Therapeutic Targets.; 2014

Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Facultad de Medicina

Community acquired methicillin resistant Staphylococcus aureus (CA-MRSA) is a relevant pathogen that produces non-complicated and complicated infections in patients without healthcare associated risk factors. Traditionally different genetic lineages have been described in the community and in hospital settings but nowadays community associated strains are replacing typical hospital associated strains (HA-MRSA). CA-MRSA strains usually carry SCCmecIV, PVL genes and are more virulent than HA-MRSA strains. Methods: Antimicrobial susceptibility of a collection of S. aureus isolates recovered from bloodstream infections at Hospital de Clínicas José de San Martín, between August 2009 and November 2010 was characterized by phenotypic methods according to CLSI guidelines. Panton Valentine Leukocidin coding genes (luk-SF/PV) and macrolide resistance genes were studied by PCR. Additionally, strains were genotyped by SCCmec typing, agr group, PFGE, spa typing and MLST. Results: Forty-eight out of the 92 (52.2 %) patients with S. aureus bacteremia included in the study were infected by MSSA, whereas 44 (47.8%) were infected by MRSA. MRSA isolates were more likely to be resistant to gentamicin, erythromycin/clindamycin, and ciprofloxacin (p