Prevalence of Staphylococcus aureus and its antimicrobial susceptibility pattern in wound swabs of patients with special reference to methicillin resistant Staphylococcus aureus

Abstract

Infection caused in wound is important cause of morbidity and fatality worldwide, especially Staphylococcus aureus (S .aureus) particularly Methicillin resistant S .aureus (MRSA). MRSA strain is one of the major cause of community and hospital acquired bacterial infection. They are also becoming increasingly multi-drug resistant and have recently developed resistance to vancomycin, which has been used successfully to treat MRSA for many years. In-vitro determination of drug resistance patterns of S .aureus is critical for the selection of effective drugs for the treatment of Staphylococci infections. Hence this study was designed to analyse the prevalence of S .aureus and its antimicrobial susceptibility pattern in wound swabs. This study was conducted in the Sree Balaji Medical College and Hospital, Chennai with aim to study the prevalence of S .aureus in particular MRSA and its antimicrobial susceptibility pattern in wound samples of patients attending a tertiary care hospital. 100 Samples were collected and processed from various clinical samples in the Department of Microbiology, Sree Balaji Medical College and Hospital. The isolated colonies were subjected to Gram’s staining and biochemical tests for the identification of organisms. Antibiotic susceptibility was done by Kirby Bauer’s Method on Muller-Hinton Agar according to “Clinical Laboratory Standards Institute” (CLSI) guidelines 2022 and cefoxitin screen test was done to detect MRSA. Among 592 wound culture during 6 month period Feb 2022 – Aug 2022, 100 yield S. aureus. Among the 100 S  aureus , 24% were Methicillin sensitive S .aureus (MSSA)  and 76% were MRSA. MRSA were susceptible to vancomycin and linezolid.Vancomycin is effective treatment against S .aureus. Hence regular surveillance and drug policy must be formulation and followed to prevent further resistance.