Inducible clindamycin resistance and erm genes in Staphylococcus aureus in school children in Kathmandu, Nepal

Abstract

Aim: Resistance to methicillin and Macrolide-Lincosamide and Streptogramins B and their association with erm genes in Staphylococcus aureus are unknown in Nepal. Materials & methods: Nonduplicate nasal swabs from 160 school children were collected from April to September 2018 and processed using standard microbiological procedures. Results: Out of 160 samples, 64 (40%) were S. aureus in which 17 (26.6%) were methicillin-resistance Staphylococcus aureus (MRSA). D-test identified 15 (23.4%) as inducible clindamycin-resistant, which were more prevalent in MRSA (76.4%) than methicillin-sensitive S. aureus (MSSA; 4.2%). 18.7% of isolates harbored the ermC gene followed by ermA (15.6%) and ermB (3.1%), and were more in MRSA than MSSA. Conclusion: To prevent treatment failure by inducible resistance, D-test must be performed on erythromycin-resistant and/or clindamycin-sensitive isolates. With the increased prevalence of methicillin-resistant S. aureus in hospital- and community-acquired infections, there has been an upsurge in resistance toward Macrolide-Lincosamide-Streptogramin type B antibiotics. This has rendered therapy difficult, thereby increasing morbidity, length of hospital-stay and cost of treatment. Therefore, the correct identification and reporting of S. aureus isolates and their susceptibility patterns, more specifically, toward methicillin, clindamycin and erythromycin is very crucial.