Comparison of the API 20E and Corning N/F systems for identification of nonfermentative gram-negative rods.

A total of 231 strains of nonfermenting gram-negative rods were tested on the API 20E system, the Corning N/F system, and conventional media. When the results of identification to species were compared, the API system agreed with the conventional system on 69% of the isolates, and the Corning system agreed with the conventional system on 79% of the isolates. Both kit systems were deficient in identifying Pseudomonas cepacia and the more unusual isolates.