Antimicrobial Susceptibility Pattern of Methicillin Resistance Staphylococcus aureus From All Clinical Samples In a Tertiary Care Center In Central Bihar

Objective The objective of this study was to evaluate the Methicillin resistance Staphylococcus aureus isolates resistance pattern among the patients attending a tertiary care center in Bihar. Materials & Method: The study included the clinical samples from the patients of either sex and across all age groups that had been submitted at the microbiology laboratory and processed. Bacterial growth identified as S aureus (based on colony morphology, Gram staining, catalase test and coagulase test) were subjected to Antimicrobial susceptibility testing (AST) by Modified Kirby-Bauer disk diffusion method and using 0 .5 McFarland as turbidity standard . Cefoxitin disk (30 µg) was used to identify MRSA isolates. Isolates with a zone of inhibition ≤21 mm were considered MRSA. Vancomycin MIC was determined by Vitek 2 compact according to CLSI guidelines. Result : Among 122 S aureus isolates, 39 (31.9%) were reported as MRSA. All isolates were sensitive to vancomycin (100%) followed by chloramphenicol (97%), linezolid (92%), teicoplanin( 90%), clindamycin (79%) and tetracycline( 76%). The isolates were resistant to penicillin (100%), followed by ofloxacin (92.30%), ciprofloxacin (87.17%), erythromycin (69.23%) gentamicin (43.58%) and levofloxacin (66.66%). Conclusion : This study shows the incidence of MRSA and their susceptibility pattern in central part of Bihar. This will help the clinicians and epidemiologists to know the local susceptibility pattern and also for monitoring resistance trends over time. It will also help the hospitals in formulating their antibiogram and antibiotic policy over the time and to choose empirical treatment wisely.