Evaluation of the API-Campy System in the biochemical identification of hippurate negative campylobacter strains isolated from faeces

Abstract

The aim was to evaluate the efficacy of the API-Campy system in the biochemical identification of 62 hippurate negative campylobacter strains isolated from the faeces. The strains were identified manually as 34 nalidixic acid susceptible C coli (NAS), 20 nalidixic acid resistant C coli (NAR), and eight C lani. The 34 strains of NAS C coli were identified as such by the API-Campy system. Of the 20 strains of NAR C coli, 15 (75%/6) were cc-rrectly identified by the commercial system. None of the five NAR Ccoli strains which were also erythromycin resistant was identified as such by the system. The eight Clari strains could not be identified by the API-Campy system because the bionumber obtained does not exist in the database of the computer system. The API-Campy system could be very useful for the identification of NAS C coli. However, failure to allow for a higher percentage of resistance to nalidixic acid in this species does not permit good identification of NAR strains. More important discrepancies are observed in Clant strains. In order to improve the identification of NAR C coli and C lari strains, it is advisable to include, or recommend as complementary, the indoxyl acetate hydrolysis test.