API and Minitek systems in identification of clinical isolates of anaerobic gram-negative bacilli and Clostridium species.

A comparison of the API and Minitek methods of biochemical testing was made on a variety of anaerobic bacteria. Although API and Minitek results were not compared to more standardized or conventional procedures of identification, multiple repeat testing of the two systems was done on routine clinical isolates and known organisms to determine (i) whether the reactions were reliably consistent, (ii) the ease of reading the two systems with respect to the frequency of questionable results, and (iii) the percentage of routine clinical isolates for which each system yielded an identification. The Minitek system gave a much lower incidence of difficult to interpret reactions. The two systems were comparable in terms of reproducibility and capability of yielding an identification of the anaerobic gram-negative bacilli and Clostridium species, but were unsatisfactory for routine use on most of the other anaerobic bacteria isolated.