Distribution of Staphylococcus species among human clinical specimens and emended description of Staphylococcus caprae.

By DNA-DNA hybridization on microplates, we identified 1,230 strains of staphylococci from human clinical specimens and determined the distribution of species. The 10 Staphylococcus species isolated most often were S. epidermidis (31.3%), S. aureus (23.3%), S. haemolyticus (12.2%), S. caprae (10.7%), S. simulans (4.4%), S. hominis (4.0%), S. capitis (3.9%), S. saprophyticus (3.6%), S. warneri (2.2%), and S. lugdunensis (1.3%). From these results, we realized that S. caprae strains were widely distributed in human clinical specimens. The description in Bergey's Manual of Systematic Bacteriology indicates that no strains of S. caprae produce acid from fructose and mannitol, but all our S. caprae strains produced acid from fructose and mannitol. Consequently, many strains of S. caprae isolated from human clinical specimens have been misidentified as S. haemolyticus or S. hominis by conventional biochemical tests. In this paper, we propose an emended description of S. caprae.