Speciation of coagulase negative staphylococci (CoNS) isolated from various clinical specimens in a tertiary care hospital of southern Rajasthan

Abstract

Abstract Background: Coagulase negative staphylococci (CoNS) are a group of staph bacteria, which generally exist as normal flora of human skin and the oral flora found on mucous membranes. CoNS in immunocompromised patients can cause variety of infections like bacteraemia, central nervous system shunt infection, intravascular catheter-related infections, endocarditis, surgical site infections, urinary tract infections, foreign body infection, endophthalmitis, peritonitis and wound, bone and joint infections as well as infections in neonates. These infections are difficult to treat because of the risk factors and the drug resistant nature of the organisms.Objective:To find out species wise distribution of Coagulase negative Staphylococci (CoNS) in various relevant clinical samples in our institute. Materials and Method:A total of 500 CoNS strains were isolated from relevant clinical specimens. CoNS strains were isolated from variety of clinical specimens. Strains were identified as CoNS on the basis of colony morphology, gram stain, catalase test and coagulase test. Conventional methods were used for species identification after confirming isolates as CoNS. Results:The most common source of CoNS isolation was blood (34%), followed by respiratory secretions (24.4%), urine (16.8%), pus (13.4%), swabs (5.4%), bodily fluid (1.4%), and others (4.6%). S.epidermidis was most frequently isolated (30.6%), followed by S.hemolyticus (25.4%), S.hominis (12.6%), S.capitis (12%), S.lugdunensis (11.4%) and S.cohnii (08%). Conclusion : As CoNS have become major cause of nosocomial infections, there is a need for rapid identification and speciation of CoNS with their antibiotic susceptibility for better management of these cases and to prevent emergence of drug resistance.