Evaluation of a commercial diagnostic PCR for the identification of Campylobacter jejuni and Campylobacter coli

Aims: DuPont Qualicon recently developed a new PCR assay for the identification of Campylobacter jejuni and Campylobacter coli . We evaluated the selectivity and utility of this assay compared with a PCR method already in use in our laboratory. Methods and Results: A group of 133 Campylobacter isolates from poultry carcass rinse samples were screened using the commercial PCR and standard PCR. Identical results were found for 89.5% (119/133) of the isolates. However, 10.5% (14/133) gave conflicting results suggesting mixed cultures. These 14 strains were retested by both PCR methods. Of these, 78.6% (11/14) showed identical results for both PCR methods after retesting; the results for the remaining 21.4% (3/14) again indicated mixed cultures. Conclusions, Significance and Impact of Study: The new multiplex PCR is a rapid and accurate alternative to more conventional PCR methods. The persistence of mixed Campylobacter cultures noted in this study suggests certain strains may be very difficult to isolate clonally by standard culture methods.