Molecular Characterization of Staphylococcus aureus Isolates from Clinical Samples in Kano State Tertiary Hospitals

Staphylococcus aureus remains a leading cause of hospital-acquired infections in Nigerian tertiary health facilities, with antibiotic resistance posing a growing public health threat. This study aimed to perform molecular characterization of S. aureus isolates recovered from clinical samples at two tertiary hospitals in Kano State, Northwest Nigeria. A total of 120 isolates were collected from wound swabs, blood cultures, and urine specimens over a six-month period. Standard microbiological techniques were used for initial identification, followed by polymerase chain reaction (PCR) targeting the nuc gene for species confirmation. Antibiotic susceptibility testing was conducted using the Kirby-Bauer disc diffusion method according to Clinical Laboratory Standards Institute (CLSI) guidelines. Virulence gene profiling, including the detection of Panton-Valentine leukocidin (pvl) and toxic shock syndrome toxin-1 (tsst-1) genes, was performed. Results showed that 68% of isolates were methicillin-resistant S. aureus (MRSA), with pvl genes detected in 44% of confirmed MRSA strains. The high MRSA prevalence reflects inadequate antimicrobial stewardship in the study settings. These findings underscore the urgent need for routine molecular surveillance of nosocomial pathogens in Northwestern Nigeria. Keywords: Staphylococcus aureus, MRSA, molecular characterization, virulence genes, Kano State.