Detection of Toxins and Antibiotic Resistance Genes Profile among Methicillin-Resistant Staphylococcus aureus (MRSA) Isolates and their types of Infection in a Tertiary Hospital in Malaysia

Objective: This study aimed to determine the molecular characteristics of virulence and antibiotics resistance genes profile of MRSA isolates and to compare between the conventional and molecular patterns of antibiotic resistance and determine the association between the MRSA virulence genes with their types of infection. Methods: A total of 60 MRSA isolates were collected from the Microbiology Laboratory of Selayang Hospital, a tertiary hospital in Malaysia. Antimicrobial susceptibility tests were performed by the disc diffusion method. The virulence and the antibiotic resistance genes were determined by PCR. Results: Among the sixty clinical isolates, there were six types of MRSA infections including cellulitis (30%), diabetic foot ulcer (28.3%), necrotizing fasciitis (13.3%), osteomyelitis (15%), catheter-related bloodstream infection (10%) and pneumonia (3.3%). Overall, lukS genes were detected in 60% followed by staphylococcal enterotoxins A (sea) gene (45%), Toxic Shock Syndrome Toxin (TSST) gene (43.3%), and 8.3% for each exfoliative toxin A (ETA) and alpha-hemolysin (hla) genes. A significant association was found between sea and hla genes with all the types of infection. The sea genes were significantly associated with cellulitis, diabetic foot ulcer, and osteomyelitis. The detection of antibiotic resistance by the molecular and conventional methods was comparable. Conclusion: This study showed that there were multiple virulences and antibiotic-resistant genes involved in the pathogenicity of MRSA infections. Both sea and hla genes have a significant association with the various types of infections. Our outcomes showed an elevated rate of lukS gene among MRSA isolates. Vancomycin-resistance was not detected among the MRSA isolates.