MIC OF VANCOMYCIN AGAINST MRSA ISOLATED FROM PATIENT VISITING A TERTIARY CARE HOSPITAL OF LALITPUR NEPAL

Abstract

Methicillin resistant Staphylococcus aureus (MRSA) majorly associated with nosocomial and community infections worldwide, are emerging as resistant strains to many antibiotics narrowing down the efficacy of antimicrobial therapy. Due to the multidrug resistance shown by MRSA, there are limited treatment options for the infections caused by this superbug. Vancomycin is used as the drug of choice for the treatment of infections caused by MRSA. The aim of this study is to detect infection caused by S. aureus as well as MRSA strains and to determine their minimum inhibitory concentration against vancomycin. In the study, total 412 clinical samples were collected during the period of December 2016 to May 2017 in Microbiology Laboratory of B&B Hospital, Lalitpur, Nepal. All the samples were analyzed by conventional culture method. Out of total samples, 210 S. aureus strains were isolated and among which 69 strains were MRSA positive. Among 412 isolates, 32.5% were from outpatients and 67.5% were from admitted patients. Likewise, 61.2% were from male patients and 38.8% were from female patients. Antibiotic resistant pattern of those 69 strains of MRSA showed that the higest number of isolate was resistant to Cefoxitin (67, 97.10%) followed by Oxacillin (55, 79.7%) and Ofloxacin (47, 68.1%). Likewise higest number of isolate was sensitive to Imipenam (62, 89.9%) and Erythromycin (62, 89.9%) followed by Meropenam (55, 79.7%) and Amikacin (53, 76.9%) whereas Vancomycin was found to be 100% effective. Minimum Inhibitory Concentration of Vancomycin against MRSA was found as 0.0125µg/ml to 2µg/ml. High prevalence of staphylococcal infection and the infection due to MRSA in the hospital patients shows the need of regular surveillance