Molecular characterization of induced clindamycin resistance in methycillin resistant Staphylococcus aureus from intensive care unit

Abstract

Out of the 148 S. aureus isolates, 82 were MRSA. Erythromycin resistance was observed in 24 isolates which expressed Cd inhibitory activity and one isolate was resistant to both Cd and Ery. The PCR study showed ermA, ermC and msrA genes. Few isolates contained both ermA and msrA genes, some ermC and msrA genes, some ermC and msrA with or without enn,A. The restriction analysis and protein profile indicated the clonal relatedness amongst the Clindamycin resistant MRSA. The present study showed high level of multidrug resistance among MRSA. High incidence of Ery induced Cd resistance is observed. Cd is one of the important alternative antibiotics to treat MRSA infections. It is advisible to include inducible Cd resistance testing as a part of routine antibiotic susceptibility as it may be missed in routine antibiotic testing to avoid treatment failure.