Usefulness of the Helicobacter pylori stool antigen test for detection Helicobacter pylori infection.

Several diagnostic tests are available for evaluating Helicobacter pylori (H. pylori) infection: histological examination, culture of gastric biopsy specimens, rapid urease test, urea breath test and serology. In this study, we assessed the reliability of a newly developed enzyme immunoassay HpSA (H. pylori Stool Antigen) kit for detecting H. pylori antigen in stool. Eighty-five patients (50 males, 35 females; mean age 41.6 +/- 9.8 years) with dyspeptic symptoms who were examined by upper gastrointestinal endoscopy. The patients with a history of previous treatment with proton pump inhibitors, bismuth compounds or antibiotics were excluded. During the endoscopic examination biopsies were taken from antrum and corpus for rapid urease test and histological examination. Stool specimens were submitted to the laboratory and HpSA test was performed. H. pylori was considered in condition with rapid urease test and histopathological examination for H. pylori positive. Forty-six of 85 patients were positive and remaining 39 patients were negative for H. pylori with the rapid urease test and pathologic evaluation. When 0.160 was adopted as the cut-off value, in accordance with the manufacturer's recommendations; stool antigen has been detected in 45 of the 46 H. pylori positive patients. The sensitivity and specificity of HpSA test were 97.8%, 94.9% respectively. These results indicate that HpSA is a highly reliable diagnostic method for H. pylori infection.