Study Of Community Acquired- Methicillin Resistant Staphylococcus Aureus (CA-MRSA) Infections and Their Antibiotic Sensitivity Pattern

Aims: Methicillin Resistant Staphylococcus aureus (MRSA) is a well recognized major source of nosocomial infections worldwide. Once prevailed in health care setup Hospital Acquired MRSA (HA-MRSA) for more than 40 years, MRSA has migrated to the community in recent years. They are termed as CA-MRSA and significantly differ from HA-MRSA in their anti-biotic sensitivity pattern. Settings and Design: A prospective study which included 87 subjects attending surgery, dermatology, orthopaedics OPD with ailments like abscesses, carbuncles, osteomylietis and skin infections who fulfilled the criteria of absence of risk factors for MRSA. Materials and Methods: The sample was cultured in laboratory and identified as Staphylococcus aureus and subsequently, as MRSA using standard methods. Antibiotic sensitivity pattern of these MRSA was studied using modified Kirby Bauers Disc Diffusion Method. Antibiotics used were Penicillin, Erythromycin, Vancomycin, linezolid, Clindamycin, Tetracycline, Co-trimoxazole, Ciprofloxacin, Cefoxitin. Results: Out of total 87 Staphylococcus aureus isolates, 22 were CA-MRSA. CA-MRSA was highly susceptible to Linezolid (100%), Clindamycin (100%), Tetracyclin (100%) and Vancomycin (100%), moderately susceptible to Ciprofloxacin(59.09%) and Co-trimoxazole(54.54%) and low to Penicillin(4.54%). The results indicate that Vancomycin, Linezolid, Tetracycline and Clindamycin are to be used as ‘Reserve Drugs’ for resistant cases. Conclusion: In the present study we found a high proportion of CA-MRSA infections- 25.29%. Most of the infections were from skin and soft tissues. A high proportion of resistance was found among CA-MRSA isolates. Susceptibility of Co-trimoxazole and ciprofloxacin was much lower than what was previously reported. As significant number of MRSA infections is being acquired from the community, treatment options of Staphylococcus aureus infections may need to be reviewed. Effective infection control programs for the community should be considered to prevent the spread of these infections.