DETECTION & CORRELATION OF INDUCIBLE AND CONSTITUTIVE CLINDAMYCIN RESISTANCE WITH METHICILLIN RESISTANCE IN COAGULASE NEGATIVE STAPHYLOCOCCI

Dr.Vidit Goyal; Dr. S Makhija

Volume : VIII, Issue : X, October - 2019

DETECTION & CORRELATION OF INDUCIBLE AND CONSTITUTIVE CLINDAMYCIN RESISTANCE WITH METHICILLIN RESISTANCE IN COAGULASE NEGATIVE STAPHYLOCOCCI

Dr. Vidit Goyal, Dr. S Makhija

Abstract :

Background: CoNS are one of those amongst the commonly isolated organisms in the clinical microbiology laboratory. Interest in CoNS is increasing because of their role as pathogens in hospital–acquired infections (HAI) associated with catheters and implanted medical devices and their marked resistance to antibiotics. CoNS strains are commonly multi–resistant to various groups of antibiotics.The macrolide–lincosamide–streptogramin B (MLSB) family of antibiotics is commonly used in the treatment of staphylococcal infections.(35) However, one important issue in clindamycin treatment is the risk of clinical failure during therapy. Materials and Methods: METHICILLIN RESISTANCE : In this study methicillin resistance was tested by cefoxitin disk (30�g) diffusion method as per CLSI guidelines, INDUCIBLE CLINDAMYCIN RESISTANCE: All CoNS isolates were tested for the inducible clindamycin resistance by Double–disk diffusion test (D–zone test) as per CLSI guidelines. Results: 234 Coagulase Negative Staphylococcial strains from different clinical specimen were processed. Methicillin resistance was shown by 65.38% isolates. Inducible clindamycin resistance was found to be 31.3% & 14.28% respectively in MRCoNS & MSCoNS Similerly constitutive clindamycin resistance was found to behigher in MRCoNS at 57.39% & then in MSCoNS (35.71%). Conclusion: Clindamycin disk induction test (D–zone test) is simple and must be done routinely in the diagnostic microbiology laboratories. Without the �D–zone test� all the CoNS isolates with inducible clindamycin resistance would be erroneously classified as clindamycin susceptible by routine testing methods. Constitutive & inducible clindamycin resistance was found to be more prevalent in MRCoNS then MSCoNS.