EVALUATION OF STAPH-ID-32 SYSTEM AND STAPH-ZYM SYSTEM FOR IDENTIFICATION OF COAGULASE-NEGATIVE STAPHYLOCOCCI

The purpose of the investigation was to evaluate two commercially avai lable identification systems: a new modification of the Staph-Zym syst em (Rosco, Tastrup, Denmark) and the Staph ID 32 API system (API Syste m, BioMerieux, Paris, France). A local standard method to be used in r outine laboratories aas also evaluated. A total of 200 staphylococcal isolates, including strains from both the American Type Culture Collec tion and the Czechoslovak Collection of Microorganisms as well as 89 c linical isolates, were used in tests of all three identification syste ms. The Staph ID 32 API system identified from 50 to 100% of the refer ence strains and 82.1% of the clinical isolates correctly. The Staph-Z ym system identified from 90 to 100% of the reference strains and 82.1 % of the clinical isolates correctly. Most misidentifications were of minor importance, but in both systems major failures appeared (Staphyl ococcus aureus was identified as a coagulase-negative staphylococcus). Both systems needed backup from a reference laboratory to determine i f two isolates were of the same strain.