IJSR International Journal of Scientific Research 2277 - 8179 Indian Society for Health and Advanced Research ijsr-7-7-15970 Original Research Paper Prevalence of Clindamycin Resistance among the Clinical Isolates of Staphylococcus aureus from a Tertiary Care Hospital in South India Dr. July 2018 7 7 01 02 ABSTRACT

The antimicrobial resistance among Staphylococcal infections is a challenge nowadays. This has led to the usage of Macrolide–Lincosamide–Streptogramin B (MLSB) antibiotics to treat these infections. However therapy may fail either due to constitutive or inducible resistance. This study was undertaken in a tertiary care hospital to detect different phenotypes including inducible clindamycin resistance in the clinical isolates of Staphylococcus aureus. A total of 135 S. aureus isolates were subjected to routine antibiotic susceptibility testing, including cefoxitin disc (30 µg). Inducible clindamycin resistance was tested by ‘D test’ as per CLSI guidelines. Among 135 S. aureus isolates, 38 (28.1 %) were resistant to methicillin, whereas 97 (71.9 %) were methicillin susceptible. Out of the 51 (37.8%) erythromycin–resistant S. aureus isolates, 12 (8.9 %) showed inducible MLS B phenotype, 9 (6.7 %) showed constitutive MLS B phenotype while the remaining 30 (22.2 %) showed MS phenotype. Inducible and constitutive resistance was found to be higher in MRSA when compared with MSSA. Performing D test routinely guides the clinician about the inducible clindamycin resistance and helps in appropriate usage of antimicrobial agents.