Prevalence and antimicrobial susceptibility pattern of methicillin-resistant staphylococcus aureus (MRSA) in a Rural Tertiary Care Hospital in North India.

ABSTRACT

The emergence of Methicillin-resistant Staphylococcus aureus (MRSA) has posed a serious therapeutic challenge. We report the prevalence and antibiotic susceptibility pattern of MRSA in the hospitalized patients in a rural tertiary care hospital in India. The study comprised of 97 Staphylococcus aureus isolated from a total of 400 clinical samples obtained from hospitalized patients. Antibiotic susceptibility testing was performed and interpreted as per standard guidelines. Methicillin resistance was detected using oxacillin and cefoxitin disc diffusion method, oxacillin screen agar and Chrom agar method, minimum inhibitory concentration using E test, and Latex agglutination method for PBP2a detection.Methicillin resistance with cefoxitin disc diffusion was 47.42%, with oxacillin disc diffusion 54.64%, Oxacillin screen agar 46.34% and Latex agglutination 45.36%. Chrom agar showed low sensitivity (77.27%) as well as specificity (79.25%) in detecting MRSA. MIC detection with E test resulted in 42.27% strains giving MIC between 8-16μg/ml. Multidrug resistance was observed in majority of MRSA strains. However, no strain was resistant to Vancomycin, Linezolid or Teicoplanin. To reduce the prevalence of MRSA, regular surveillance of hospital acquired infection and monitoring of antibiotic susceptibility pattern is the need of the hour. Proper detection of all MRSA with rapid and accurate methods must be done as a routine laboratory procedure.