Characterization of coagulase-negative staphylococci by primer-specific polymerase chain reaction and ribotyping

Abstract

Objective: To analyze, by primer-specific polymerase chain reaction (PCR) and ribotyping, coagulase-negative staphylococci (CNS). Methods: Forty-five clinical isolates of CNS were identified by the API ID32 STAPH system and ribotyping. Additionally, primer-specific PCR was evaluated for identification of clinical strains of Staphylococcus epidermidis. Results: Forty-five isolates of CNS from neonates with nosocomial bacteremia were studied. The results of the S. epidermidis-specific PCR were compared with those obtained using ribotyping and the API ID32 STAPH system. Excellent congruence was found between primer-specific PCR and ribotyping. Primer-specific PCR proved to be a fast and reliable method for the identification of S. epidermidis strains. According to the primer-specific PCR and ribotyping analysis, a few CNS isolates were found to be incorrectly identified by the API ID32 STAPH system. Conclusions: Primer-specific PCR is a fast and reliable method for the identification of S. epidermidis. Primer-specific PCR in combination with ribotyping is a promising approach for studying the epidemiology of S. epidermidis and other CNS species in hospital.