Inducible clindamycin resistance in coagulase negative staphylococci

Abstract

Induced clindamycin resistance poses a major problem for the use of this drug to treat staphylococcal infections. An infectious etiology is often implicated in the presence of CoNS in clinical specimens. A total of 183 isolates of Staphylococci spp. recovered from different clinical specimens were studied. A coagulase test was done to select coagulase negative Staphylococci, and they were confirmed by conventional microbiological techniques. Using the double disc approximation test, induced clindamycin resistance was detected (D-test). The D test was used to detect the inducible clindamycin resistance phenotype in erythromycin resistant and clindamycin sensitive isolates. A micro titer plate test was used to determine biofilm development in these isolates. One hundred and twenty eight isolates from various clinical specimens were identified as proven CoNS, which were distributed across six different species’. haemolyticus, the most common species of CoNS isolated, was isolated from all types of specimens. The present study revealed the strong association of biofilm with inducible clindamycin resistance among the CoNs isolates.