Antimicrobial Resistance of Nosocomial Strains ofStaphylococcus aureusin Russia: Results of a Prospective Study

Abstract

A total of 879 Staphylococcus aureus clinical isolates from 17 medical institutions in different regions of Russia were tested. Susceptibility to 18 antimicrobials was determined by agar dilution in accordance with the NCCLS recommendations. The most potent antimicrobials were glycopeptides, linezolid, and fusidic acid, to which no resistance was found. Other antimicrobials with low frequency of non-susceptibility were mupirocin (0.3%), trimethoprim/sulfamethoxazole (0.8%), quinupristin/dalfopristin (1.8%) and rifampicin (7.0%). Fluoroquinolones displayed moderate activity (5.8% of non-susceptible strains to moxifloxacin, 9.1% to levofloxacin, 13.1% to ciprofloxacin). High rates of non-susceptibility were found to clindamycin (27.1%), gentamicin (30.7%), tetracycline (37.1%), erythromycin (39.6%) and chloramphenicol (43.1%). The prevalence of oxacillin-resistant S. aureus (ORSA) was 33.5% and varied from 0% to 89.5% in different hospitals. ORSA were isolated most frequently in the burn units (77.5%), intensive care units (54.8%), trauma and orthopedics units (42.1%). This is the first multicenter study published of antimicrobial resistance of S. aureus in Russia which meets international standards.