A study of coagulase negative staphylococci associated blood stream infections in pediatric patients in a tertiary care hospital in karnataka

Background: Coagulase-negative Staphylococcus (CoNS) found in the normal skin flora and mucous membranes have recently got attention as a potential pathogen, specifically for nosocomial infections. Recent reports suggest coagulase negative Staphylococci as the most common pathogens of blood stream infections. Aims: To identify and speciate various species of coagulase negative Staphylococci isolated from bloodstream infection and determine their antimicrobial resistance pattern. Materials and methods: We collected 224 strains of different CoNS species from positive blood cultures obtained from paediatric patients aged less than 6 years during a period of three years-from January 2012 to December 2014.Isolates were identified and antimicrobial susceptibility was performed by MicroScan Walkaway SI system (Siemens). Results: Among the 224 pediatric patients enrolled, 120 were male and 104 were female babies. Of the 224 clinical isolates, Staphylococcus hominis was the most common species found 89(39.7%). The overall drug resistance among the species ranged from 8.5% to 87% to all the drugs tested except to Vancomycin, Linezolid and Streptogramins which were 100% sensitive. The highest drug resistance was exhibited towards Penicillin and Ampicillin (86.6%) and Oxacillin (69.7%). The minimum drug resistance was shown towards Gentamicin (12.3%) and Rifampicin (8.5%). S.hyicus, S.cohnii, S.xylosus, S.saprophyticus, S.warneri, S.capitis were 100% sensitive to Gentamicin. Conclusions: CoNS have emerged as one of the important cause of blood stream infections. High rate of resistance is exhibited against commonly used antibiotics like Penicillins and Cephalosporins. Hence empirical use of antibiotics has to be avoided to prevent development of multidrug resistant strains.