Evaluation of a triplex PCR assay to discriminate Staphylococcus aureus from coagulase-negative Staphylococci and determine methicillin resistance from blood cultures.

A triplex PCR targeting the 16S rRNA, mecA, and nuc genes was developed for identification of staphylococci and detection of methicillin resistance. After validation of the assay with a collection of strains of staphylococci and enterococci (n = 169), the assay was evaluated with cultures of blood with gram-positive cocci from 40 patients. Accurate results were obtained for 59 (98%) of 61 cultures within 6 h of growth detection.