Prevalence of Inducible Clindamycin Resistance Staphylococcus aureus Associated with Wound Infection in Central Nepal.

BACKGROUND

To determine the prevalence of inducible clindamycin resistance among methicillin-resistance Staphylococcus aureus (MRSA), and to detect the presence of mecA and ermC genes among MRSA recovered from hospital patients in central Nepal.

METHODS

Staphylococcus aureus isolated from a total of 289 clinical specimens consisting of pus and wound swabs were analyzed and identified. The MRSA strains were screened using a cefoxitin (30 µg) disc following the CLSI procedure and a double-disc test (D-test) was applied to investigate iMLSB-resistant phenotypes among the MRSA isolates. The bacterial genomic DNA was extracted and mecA and ermC genes were detected using specific primer pairs.

RESULTS

Among the 64 S. aureus strains, 39.1% of the isolates were MRSA. The prevalence of inducible clindamycin resistance among MRSA was observed to be 48%. All MRSA (100%) isolates were resistant to penicillin and amoxicillin, whereas all strains were susceptible to linezolid, vancomycin, teicoplanin, and tigecycline. Among MRSA isolates, 8% carried the mecA gene and 13.3% of iMLSB isolates were positive for the ermC gene.

CONCLUSIONS

A high rate of inducible clindamycin resistance among MRSA was observed. To identify the status of antibiotic resistance among S. aureus, further genomic-based studies are required.