ANTIBIOTIC SUSCEPTIBILITY TEST OF Staphylococcus aureus FROM CLINICAL SAMPLES OF PATIENTS VISITING A TERTIARY CARE CHILDREN HOSPITAL OF KATHMANDU, NEPAL

Abstract

Staphylococcus aureus is one of the most important and common cause of community-acquired as well as hospital-acquired infections. Moreover, methicillin resistant strains of S. aureus, usually being resistant to several antibiotics, are now presenting the major threat in many different countries throughout the world. The aim of this study was to determine the prevalence of infection caused by S. aureus as well as MRSA strains and to determine their antimicrobial susceptibility pattern. A cross-sectional study was carried out from September to December 2018 at IFCH, Kathmandu, Nepal, in which 227 S. aureus isolated from 961 clinical specimens. Methicillin-resistant Staphylococcus aureus (MRSA) identified by using the Cefoxitin (30 μg) disc diffusion method followed by the Clinical and Laboratory Standards Institute (CLSI 2012) guidelines. Among 227 isolates, 55.9% (n=127) were from inpatients and 44.1% (n=100) were from outpatients. Likewise, 62.5% (n=142) were from male patients and 37.4% (n=85) were from female patients. Overall, the highest percentage of S. aureus isolation (32.2%) was found in toddler’s age group. Antibiogram of all 227 S. aureus strains showed chloramphenicol (78.4%) was most effective drug, followed by meropenem (76.2%), clindamycin (74%) and the least effective drug was found to be erythromycin (37.4%). Prevalence of MRSA, using cefoxitin discs, was found to be 48% (n=109) whereas, vancomycin was found to be 100% effective. Out of 109 MRSA strains, the maximum number of strains (n=62) were isolated from the inpatients. Similarly, in overall, the highest number of MRSA isolates (n=33) was found in the patients of toddlers age group. High prevalence of staphylococcal infection and the infection due to MRSA in the hospital patients showed the need of regular surveillance. The study also showed the need of evaluation of antibiotic disks before the study in Nepal