Detection of inducible clindamycin resistance in staphylococcus aureus isolated from different clinical samples

Abstract

Background: Staphylococcus aureus is one of the most common causes of nosocomial and community-acquired infections in all parts of the world. Prevalence of methicillin resistance in staphylococci has increased and become a serious concern worldwide. Clindamycin resistance is on the rise among clinically important staphylococcal isolates. Objectives: Identification and antimicrobial susceptibility testing of Staphylococcus aureus isolates from different clinical samples by using Standard Microbiological procedures as per CLSI guidelines. Detection of Methicillin resistant Staphylococcus aureus was carried out by using Cefoxitin screening test. Inducible clindamycin resistance among clinical isolates of Staphylococcus aureus was tested by using D-test and Vitek -2 compact automated system. Methods: Total 107 Staphylococcus aureus isolates from different clinical specimens were processed in the microbiology department at B.K.L. Walawalkar rural medical college. All samples were tested for Cefoxitin screening test and detection of Inducible clindamycin resistance was carried out by using D test and Vitek 2 panel automated system. Results: Out of 107 samples of Staphylococcus aureus isolates, cefoxitin screening test result showed 19(17.75%) positive result (MRSA). Percentages of inducible clindamycin resistance were higher amongst MRSA as compared to MSSA. The study revealed 32 (29.90 %) isolates are inducible clindamycin resistance detection result were positive (are Macrolides/ Lincosamides/ Streptogramins MLSB phenotype inducible) by Vitek 2 automated system. Conclusion: Detection of inducible clindamycin resistance should be included in the routine antimicrobial susceptibility testing, as it will help in guiding the empirical therapy.

Keywords

• methicillin resistant staphylococcus aureus
• cefoxitin screening test
• inducible clindamycin resistance