Antibiotic susceptibility of methicillin-resistant Staphylococcus aureus (MRSA) strains isolated at tertiary care hospital in Riyadh, Saudi Arabia

Staphylococcus aureus is an important human pathogen that has a major impact on public health. The objective of the present work was to determine the prevalence and the pattern of antibiotic susceptibility in S aureus (MRSA) isolates from the King Khalid University Hospital (KKUH) in Riyadh, Saudi Arabia. The isolates were collected from different body sites of infection and the antibiotic susceptibility was confirmed on the Vitek 2 system. A total of 371 MRSA isolates from clinical samples were received over a 12-month period from January 2021 to December 2021. The results showed that infection was predominant among males (55.8%) and most of the isolates occurred in the older age groups, with a mean age of 43.7 years and an age span from <1 to 89 years old. The majority (34.5%) recovered from wound infection followed by (14.6%) from blood. We have observed peaks of MRSA infections during the autumn, especially in September and November. All MRSA isolates were resistant to Amoxicillin + clavulanic acid, Ampicillin, Imipenem, Oxacillin, Cloxacillin, and Penicillin while all isolates were sensitive to Daptomycin and Nitrofurantoin. Furthermore, Vancomycin was resistant in (0.3%) of MRSA isolates, and (2.9%) was resistant to Linezolid. The current study concluded that MRSA strains had developed resistance toward 24 tested antibiotics, including the previous effective drugs vancomycin and linezolid. Therefore, there is an urgent need for continuous review of infection control practices to prevent any further spread of resistant strains.