Evaluation of a newly developed rapid stool antigen test using an immunochromatographic assay to detect Helicobacter pylori.

The ASAN Easy Test H. pylori is a newly developed rapid test for Helicobacter pylori that uses a stool antigen immunochromatographic assay (S-ICT). The aim of this study was to evaluate this kit for the diagnosis of H. pylori under various histological conditions. We enrolled 266 consecutive patients undergoing a routine health checkup and endoscopy with biopsy. H. pylori infection was confirmed if at least 2 out of the 3 following tests were positive: histology, real-time polymerase chain reaction (PCR), and the stool antigen test by enzyme immunoassay (S-EIA). Histological examination was performed using hematoxylin-eosin and silver staining. Real-time PCR was performed with a probe for the UreA gene as described previously. The S-EIA and the evaluated kit were used according to the manufacturers' instructions. Of the 266 patients, 209 were eligible for participation. The evaluation results were as follows: sensitivity, 84.5%; specificity, 96.2%; positive-predictive value, 95.6%; negative-predictive value, 86.4%; and accuracy, 90.4%. The performance of the kit was unaffected by histological findings such as atrophic gastritis, ulcers, and intestinal metaplasia. The newly developed S-ICT assay is a non-invasive rapid test for the diagnosis of H. pylori that exhibits good performance in routine health checkup patients.