Staphylococcus aureus is a leading cause of hospital and community acquired infections globally. Surveillance of prevalence and antibiotic susceptibility patterns is important to ensure appropriate antibiotic prescription. The aim of this study was to determine the prevalence and susceptibility patterns of Staphylococcus aureus isolated from clinical specimens in a tertiary referral and training hospital.A retrospective study was conducted at the Mater Misericordiae Hospital, Nairobi.It involved analyzing records of specimens analyzed between January 2014 and December 2018. Strains phenotypically resistant to <3 non β-lactam antimicrobial categories were defined as non-multidrug-resistant MRSA (nmMRSA) and strains that were resistant to ≥3 non-β-lactam antimicrobial groups were defined as multidrug-resistant MRSA (mMRSA). A specimen was categorized as Penicillin susceptible (PSSA) if susceptible to Penicillin and Oxacillin, MSSA if resistant to Penicillin and susceptible to Oxacillin, and MRSA if resistant to Oxacillin and Penicillin.ResultsPSSA accounted for 60.85%, (401/659)of S.aureus cultured.The prevalence of MSSA was 38.54%(254/659).MRSA was the least prevalent.(0.61%,4/659).No multi-drug Methicillin resistant S. aureus were isolated in the five-year period.PSSA accounted for 60.85%(401/659)of all S.aureus isolates.100% of MRSA isolated was sensitive to Vancomycin, Linezolid, Tigecycline, Tetracycline and Rifampicin. MRSA was resistant to Clindamycin and Erythromycin.Conclusion;The prevalence of MRSA was low compared to previous studies.All strains isolated were non-multidrug resistant.There was no resistance to Vancomycin detected.Penicillins are still a viable option in the treatment of majority of S.aureus infections in our setting.

Staphylococcus aureus (S. aureus) is a leading cause of hospital and community acquired infections globally. Methicillin-resistant Staphylococcus aureus (MRSA) prevalence has been reported to be high in various settings and is associated with increased morbidity, mortality and risk of nosocomial outbreaks. Surveillance of prevalence and antibiotic susceptibility patterns is important to ensure appropriate antibiotic prescription. The objective of our study was to establish the prevalence of S. aureus, to identify patterns of susceptibility to commonly used antibiotics and quantify contemporary penicillin resistance among S. aureus. A retrospective study was conducted at the Mater Misericordiae Hospital, Nairobi. The study involved a review of non-duplicate records of specimens analyzed between January 2014 and December 2018.A specimen was categorized as Penicillin susceptible (PSSA) if susceptible to Penicillin and Oxacillin, MSSA if resistant to Penicillin but susceptible to Oxacillin, and MRSA if resistant to Oxacillin. We present proportions of S. aureus that was PSSA, MSSA and MRSA. Multivariate logistic regression was used to determine the association between the presence of S. aureus isolates and the source of the clinical specimen (in vs. outpatient), age and gender. A total of 659 specimens of S. aureus were analyzed in the 5-year period. ​​PSSA was the most prevalent organism seen (60.85%) while MRSA was the least prevalent (0.61 %). Most S. aureus was isolated in pus from wound swabs-644 (73. 3%). A significant increase in susceptibility of S. aureus to Penicillin and Amoxicillin-clavulanic acid was observed during the study period however, sensitivity to Amoxicillin declined. This study demonstrated a high prevalence of Penicillin Sensitive S. aureus and a low prevalence of MRSA.