Correlation studies of entero-set 20, API 20E and conventional media systems for Enterobacteriaceae identification

The Entero-Set kit (Fisher Diagnostics) is a 20-biochemical-test system used in the identification of members of the Enterobacteriaceae. This kit was compared with the API 20E (Analytab Products) and conventional media systems, using 505 (303 stock and 202 clinical) strains of Enterobacteriaceae. When the Entero-Set and API 20E results were compared with those of the conventional media system, the Entero-Set performed as well as the API 20E in overall identification. Comparison of common biochemical tests among the various systems showed that citrate, arabinose, adonitol, inositol, and malonate gave correlations below 90%. The majority of the discrepancies were found among stock cultures. In addition, most discrepancies occurred with species of Enterobacter, Salmonella, Proteus, Klebsiella, and Serratia. Reproducibility studies showed the Entero-Set system to perform with a high degree of accuracy and reproducibility.