Inducible Clindamycin Resistance In Staphylococcus Aureus Isolates From School Children.

Introduction-Staphylococcus aureus shows increasing resistance to macrolide-lincosamide-streptogramin B (MLSB) antibiotics due to the presence of the erm gene, which mediates either inducible (iMLSB) or constitutive (cMLSB) resistance.Inducible resistance poses diagnostic challenges, as isolates may appear erythromycinresistant but clindamycin-sensitive in routine tests.Failure to detect iMLSB can result in therapeutic failure.Performing a D-test is essential to identify inducible resistance and ensure appropriate antibiotic selection for effective treatment of Cutaneous and subcutaneous infections. Objective-This study was undertaken to determine the presence of MLSB resistance phenotypes in Staphylococcus aureus isolates obtained from school children (carriers), using an in-vitro phenotypic detection method. Materials and methods-142 non-duplicate Staphylococcus isolates were tested for antibiotic susceptibility by Kirby-Bauer method, and inducible clindamycin resistance was detected using the D-test on erythromycin-resistant strains per CLSI guidelines. Result-Out of 142 isolates, 46 (32.39%) were erythromycin-resistant.Among them, 16 (11.26%)showed inducible and 6 (4.2%) constitutive clindamycin resistance.Twenty-four (16.90%) had the MS phenotype.These findings highlight the importance of D-testing in erythromycin-resistant strains to detect iMLSB resistance and ensure appropriate antibiotic therapy, preventing treatment failure. Conclusion-The low prevalence of inducible clindamycin resistance suggests rational antibiotic use; however, continuous surveillance is essential to monitor emerging resistance and prevent outbreaks of resistant Staphylococcus aureus strains.