HUMAN ISOLATES OF STAPHYLOCOCCUS-CAPRAE - ASSOCIATION WITH BONE AND JOINT INFECTIONS

Staphylococcus caprae is a coagulase-negative, DNase-positive member o f the genus Staphylococcus usually associated with goats, but since 19 91 a few laboratories have reported isolating the organism from human clinical specimens, We report on the isolation of 14 strains from huma n specimens and note that 10 strains were obtained from patients with bone and joint infections, Nine of the 10 infections started with trau matic fractures, and the other was a case of mastoiditis, Seven of the se 10 infections were in patients with orthopedic prostheses, which ap pears to be a risk factor, Three of the 14 strains were from transplan t patients, For three of the patients, S. caprae was the only organism isolated. S. caprae may be misidentified because it is not represente d in the current MicroScan or Vitek identification systems which are i n use in many laboratories, but the organism can be differentiated by a few biochemical tests, S. caprae produces positive results for DNase , pyrrolidonyl aminopeptidase, and acid production from mannitol and m altose; it produces negative results for ornithine decarboxylase and t ube coagulase.