High occurrence of high-level mupirocin & chlorhexidine resistant genes in methicillin resistant staphylococcal isolates from dialysis unit of a tertiary care hospital

Chronic hemodialysis (CHD) patients are vulnerable to infections, including infections by methicillin-resistant staphylococci (MRS) because they are repeatedly exposed to the hospital environment and often receive prolonged courses of antibiotics, besides being immunocompromised1. Nasal carriage of MRS in hospital personnel also adds to the colonization pressure in healthcare facilities, acting as reservoirs for transmission to these patients1. Routine use of mupirocin and chlorhexidine in healthcare settings has contributed to acquisition of resistance to these antimicrobial agents among microbes which cause outbreaks in these settings2. Resistance to mupirocin is of low-level (mutations in the chromosomal ileS gene) or high-level [by a plasmid-mediated mupA (ileS2) gene, encoding a novel IleS]3. Chlorhexidine resistance is conferred by the plasmidmediated qacA/B genes which encode proton-dependent multidrug efflux pumps4. We conducted a cross-sectional study to detect the presence of mupirocin and chlorhexidine resistance among methicillin resistant staphylococcal isolates obtained from the dialysis unit of a tertiary care hospital.