Screening of Toxin Genes in Methicillin-Resistant Staphylococcus aureus Clinical Isolates from a Hospital Setting in a Tertiary Hospital in Northern Cyprus

Methicillin-resistant Staphylococcus aureus (MRSA) is a significant opportunistic pathogen with a wide repertoire of virulence characteristics. Data regarding the molecular profile of MRSA in Northern Cyprus is limited. The current study aimed to examine the virulence profiles of MRSA with a focus on toxin-associated factors. Ninety-one S. aureus isolates collected at a university hospital were included in the study. Identification and antibiotic susceptibility testing were performed with BD Phoenix™ automated system. Methicillin resistance was evaluated by the disc diffusion assay and mecA detection. The presence of nuc was confirmed by conventional PCR. Confirmed MRSA isolates were assessed for the presence of virulence genes hla, eta, etb, etd and tst using molecular methods. Among 91 S. aureus isolates identified as MRSA using the BD Phoenix™ platform, 80.85% (n = 76/91) were confirmed as MRSA using phenotypic and genotypic methods. All confirmed MRSA isolates (n = 76, 100%) were positive for the nuc. MRSA rates were statistically higher in elderly inpatients. The prevalence of toxin-encoding genes was 97.3% (n = 74/76) for hla, 2.63% (n = 2/76) for eta, 1.3% (n = 1/76) for etb, and 2.63% (n = 2/76) for tst. None of the screened isolates harbored the etd gene. These results represent the first report to investigate multiple virulence factors in MRSA isolates in Northern Cyprus.