Identification of Staphylococcus species with the API STAPH-IDENT system

Abstract

The API STAPH-IDENT system was compared with conventional methods for the identification of 14 Staphylococcus species. Conventional methods included the Kloos and Schleifer simplified scheme and DNA-DNA hybridization. The API STAPH-IDENT strip utilizes a battery of 10 miniaturized biochemical tests, including alkaline phosphatase, urease, β-glucosidase, β-glucuronidase, and β-galactosidase activity, aerobic acid formation from D-(+)-mannose, D-mannitol, D-(+)-trehalose, and salicin, and utilization of arginine. Reaction of cultures were determined after 5 h of incubation at 35°C. Results indicated a high degree of congruence (>90%) between the expedient API system and conventional methods for most species. The addition of a test for novobiocin susceptibility to the API system increased the accuracy of identification of S. saprophyticus, S. cohnii, and S. hominis, significantly. Several strains of S. hominis, S. haemolyticus, and S. warneri which were difficult to separate with the Kloos and Schleifer simplified scheme were accurately resolved by the API system.