[Evaluation and comparison of the Helicobacter pylori stool antigen test and the gastric mucosal antigen test]

Abstract

Objective: To evaluate the reliability of an enzyme-linked immunosorbent assay by the Helicobacter pylori (H. pylori) stool antigen test for the detection of H. pylori infection.

Methods: Stool specimens were collected from 224 patients who received upper gastrointestinal endoscopic examination for gastrointestinal symptoms. H. pylori status was evaluated by five different tests: culture, histology, biopsy rapid urease test, H. pylori stool antigen test, and H. pylori gastric active mucosal antigen test (parts of the patients). A commercial kit using an enzyme-linked immunosorbent assay was used to examined H. pylori antigen in the stool or in the gastric active mucosa. H. pylori status was defined as positive when two of the three tests (culture, histology and biopsy rapid urease test) were positive.

Results: 137 patients were diagnosed as H. pylori-positive. The H. pylori stool antigen test was positive in 143 patients and negative in 81 patients. The sensitivity and specificity were 96.4% and 87.4%, respectively. The overall accuracy was 92.9%. 39 patients were examined H. pylori antigen in the gastric active mucosa, and 27/39 were diagnosed as H. pylori-positive. The H. pylori gastric active mucosal antigen test was positive in 28 patients and negative in 11 patients. The H. pylori stool antigen test was positive in 30 patients and negative in 9 patients. The corresponding rate between gastric active mucosa and stool was 94.9%.

Conclusion: The H. pylori stool antigen test is a simple, non-invasive method for accurate diagnosis of H. pylori infection.