Evaluation of the ProSpecT Microplate Assay for detection of Campylobacter: a routine laboratory perspective

Objectives  To evaluate the use of the new enzyme-linked immunosorbent assay, the ProSpecT Campylobacter Microplate Assay (Alexon-Trend, Minneapolis, MN, USA), which allows 2-h detection of both Campylobacter jejuni and Campylobacter coli antigen directly in stool specimens.
Methods  Over 4 months, all stool samples preserved in Cary–Blair medium, or fresh specimens, from non-hospitalized children and HIV-infected patients (adults and children), submitted to our laboratory were evaluated with the ProSpecT Campylobacter Microplate Assay. Results were compared with those obtained by routine culture methods using both a specific medium and a filtration method for the recovery of Campylobacter spp.
Results  Of the 1205 stool specimens cultured, 101 were found to be positive for either C. jejuni or C. coli , giving an overall recovery rate of 8.38%. Ninety samples were positive by both culture and ProSpecT Campylobacter Microplate Assay, and 11 were positive by culture only, giving a sensitivity of 89.1%. In addition, of 1104 samples negative by culture, 25 were initially positive by ProSpecT Campylobacter Microplate Assay. We found no cross-reaction with other bacterial enteropathogens isolated from stool specimens. These results thus confirm a high specificity (97.7%) for both C. jejuni and C. coli. The positive and negative predictive values found were 78.3% and 99%, respectively. There was no statistically significant difference in sensitivity and specificity if the stool was fresh or preserved with Cary–Blair medium.
Conclusion  These data suggest that the ProSpecT Campylobacter Microplate Assay is a rapid and easy-to-use test for the detection of both C. jejuni and C. coli in stool specimens. It could be used for patients for whom early antibiotic therapy is needed or for epidemiologic studies.