ABSTRACT

Background: The resistance to antimicrobial agents among Staphylococci is an increasing problem. Clinical failure of clindamycin therapy has been reported due to multiple mechanisms that confer resistance to macrolide, lincosamide and streptogramin antibiotics.
In-vitro, routine tests for clindamycin susceptibility may fail to detect inducible clindamycin resistance due to erm genes resulting in treatment failure, thus necessitating the need to detect such resistance by a simple D-test on a routine basis.
Aim: The aim of the study was to assess the frequency of inducible clindamycin resistance in clinical isolates of Staphylococci by using D-test on a routine basis to guide therapy.
Materials & Methods: A total of 108 Staphylococcus species were isolated from various clinical samples received in the microbiology department over a period of one year (February 2011 – January 2012) and were subjected to the study. Inducible clindamycin resistance was tested in these isolates by D-test as per CLSI guidelines.
Results: Among the 108 Staphylococci isolates, 32 (29.62 %) showed inducible clindamycin resistance and belonged to iMLS phenotype. All 32 isolates were B Methicillin Resistant Staphylococcus aureus (MRSA).
Conclusion: The study showed that D-test should be used as a mandatory method in routine disc diffusion testing to detect inducible clindamycin resistance in Staphylococci for the proper treatment of the patients.