Prevalence and Susceptibility Pattern of Methicillin Resistant Staphylococcus aureus (MRSA)

Objective: To determine the prevalence and susceptibility pattern of MRSA isolated at a single tertiary care hospital at Rawalpindi and to compare MRSA susceptibility pattern with MSSA (Methicillin sensitive staphylococcus aureus). Study Design: Descriptive cross sectional data based study. Place and Duration of Study: The study was conducted at department of microbiology, Pakistan Railways Hospital Rawalpindi, from January 2012 to March 2014. Materials and Methods: Culture reports data were retrospectively collected from microbiology laboratory. The antibiotic susceptibility patterns of all staphylococcal strains were determined by modified Kirby Bauer antibiotic sensitivity method. The data was analyzed on the basis of antimicrobial susceptibility pattern, location of the patient (OPD, ward patients) and specimen type (wound swab, pus, HVS & effusions). Results: A total of 167 isolates were used in the study. Among these isolates 55 (33%) were MRSA and 112 (67%) were MSSA. The majority of S.aureus isolates were obtained from patients with skin and soft tissue infections. All (100%) strains of MRSA isolated during study period were found to be sensitive to Vancomycin, and linezolid and 95% to Teicoplanin, as well as they showed higher susceptibility against chloramphenicol (88%),Fusidic acid (70%) and Rifampin (48%)while MSSA showed higher susceptibility to Gentamicin (92%),Erythromycin (86%) and Ciprofloxacin (71%) as compared to MRSA. Conclusion: This study showed a high prevalence of MRSA in this tertiary care hospital of Rawalpindi. Present study conclusively shows that Vancomycin, Linezolid and Teicoplanin remain the first choice of treatment for MRSA infections. Still alternative antibiotics like chloramphenicol, Fusidic acid, and Rifampin are available to maintain and reserve the efficacy of Vancomycin, Teicoplanin and Linezolid in treating life threatening illnesses.