Rapid and automated identification of Enterobacteriaceae with the abbott MS-2 system and API-20E versus conventional methods.

The ability of the MS-2 (Abbott Laboratories, Diagnostic Division, Dallas, Texas) to rapidly identify Enterobacteriaceae, was evaluated. The results of the MS-2 and of the Analytab API-20E test strip were compared with those obtained from conventional tubed media. The MS-2 and API-20E completely agreed with the conventional method for 92% and 95% of the organisms, respectively. Only 0.5% (MS-2) to 0% (API-20E) of the organisms tested led to complete disagreement. Approximately 6% (MS-2) and 3.5% (API-20E) of the organisms would have shown complete agreement if additional tests had been done. For 1.5% of the organisms the octal code could not be found in the API-20E profile index. It was concluded that the MS-2 system provides a rapid (5 to 6 h) and accurate method for the routine identification of Enterobacteriaceae.