Detection and Prevalence of Methicillin and Vancomycin Resistant Staphylococcus aureus among Clinical Isolates in ESUTH, Enugu State, Nigeria

Abstract

The increasing rate of drug resistance associated with methicillin resistant Staphylococcus aureus and the emergence of vancomycin resistant trait is a great problem in human disease treatment and management. The present study was carried out to determine the prevalence, antibiotic susceptibility profile of MRSA, and vancomycin resistant S. aureus among patients at ESUT Teaching Hospital, Enugu. Four hundred and fifty (450) Clinical samples were collected between April and November 2018. All S. aureus were recovered using standard laboratory method. Antibiotic susceptibility pattern was determined using modified Kirby Bauer disc agar diffusion method. Methicillin and vancomycin resistance were determined using cefoxitin (30µg) and vancomycin (30µg) disc diffusion, respectively. Penicillin binding protein 2a was detected through rapid latex agglutination assay while nitrocef stick was used for screening of beta lactamase production. Eighty three (18.4%) isolates out of 450 clinical samples were confirmed and characterized as Staphylococcus aureus. Twenty three (27.7%) of the isolates were MRSA. All (100%) the MRSA isolates were susceptible to vancomycin. The result of antibiotic susceptibility test showed much resistance to β-lactam antibiotics. The multiple antibiotics resistance index (MARI) showed that 66 (79.5 %) were resistant to 3 or more antibiotics (MARI ≥ 0.4). Seventy two percent of the MRSA were multi drug resistant. Seventy four (89.1%) isolates produced beta-lactamase while Penicillin binding protein 2a was detected in 13.2% of MRSA isolates. The results suggest the need for methicillin resistance S. aureus regular surveillance studies as well as institution of infection control measures, antibiotic stewardship programme and amendment of antibiotic regimen guidelines for MRSA infections.