| Abstrakt: |
This study aimed to determine resistance to antimicrobials of Staphylococcus aureusstrains isolated from clinical specimens in Lithuanian hospitals and to identify the genes conferring resistance and virulence. The study was carried out from June 2019 to September 2021. S. aureusstrains were isolated from skin, soft tissues, blood, lower respiratory tract, urine and other specimens. Antibiotic susceptibility testing was performed using the disc diffusion method according to EUCAST guidelines. All isolates were analyzed for detection of the ermA, ermC, mecA, mecC, tetK, tetM, and lukF-PVgenes by multiplex real-time PCR. The 16S rRNA coding sequence was applied as an internal PCR control. Altogether, 745 S. aureusstrains were analyzed. Antimicrobial susceptibility testing revealed that all isolates were susceptible to rifampin and vancomycin. Of the 745 strains, 94.8% were susceptible to tetracycline, 94.5% to clindamycin, and 88.3% to erythromycin. The lowest susceptibility rate was found for penicillin (25.8%). Six percent of the tested strains were methicillin-resistant S. aureus(MRSA). The majority of methicillin-resistant strains were isolated from skin and soft tissues (73.3%), with a smaller portion isolated from blood (17.8%) and respiratory tract (8.9%). The ermCgene was detected in 41.1% of erythromycin-resistant S. aureusstrains, whereas ermAwas detected in 32.2% of erythromycin-resistant S. aureusstrains. 69.2% of tetracycline-resistant S. aureusstrains had tetKgene, and 28.2% had tetMgene. 7.3% of S. aureusisolates harbored lukF-PVgene. The frequency of the pvlgene detection was significantly higher in MRSA isolates than in methicillin-susceptible S. aureusisolates (p< 0.0001). |
