Clinical Microbiology and Antimicrobial Chemotherapy. 2012; 14(3):201-208
To reveal molecular types of nosocomial and community-acquired strains of S. aureus in different regions of Russia.
575 (187 MRSA and 388 MSSA) strains, isolated from pediatric patients during multicenter studies (1997–2008) from 36 medical institutions in 24 Russian cities were included in the study. For molecular typing 186 strains with unique resistance profile within each ward of each medical institution were selected. The following typing methods were used: MLVA, spa, SCCmec and MLST.
According to MLVA, methicillin-susceptible strains (n=117) were clustered to 80 types, that could be placed into 10 genetic groups that differ in not more than 1 VNTR locus. At the same time the vast majority of MRSA strains (n=85) were represented by the only genetic group (with the exception of 3 isolates), consisted of 17 MLVA types. Only 2 types of SCCmec were detected (III and IV). According to MLST results the vast majority of strains belong to ST 239 and ST 8. Community-acquired MRSA had the same MLVA, spa and SCCmec types as nosocomial ones: t008 SCCmec IV (n=9), t037 SCCmec III (n=4) and t030 SCCmec III.
In our study, independently of the geographic location, place of onset of infection, and time period, the dominating molecular types of MRSA were ST8, t008, SCCmec IV and ST239, t030 and t037 SCCmec III.