Role of Helicobacter Pylori stool antigen test in the diagnosis of Helicobacter Pylori infection

Introduction: Helicobacter pylori (H. pylori) infection is common in developing countries. There are various invasive and non-invasive methods for diagnosing H. pylori infection. Stool antigen test is a new non-invasive method to diagnose H. pylori infection. In this study we evaluated the diagnostic accuracy of HpSA for H. pylori infection in patients with gastrointestinal (GI) complaints. Methods: Sixty patients including 28 men and 32 women with mean age of 49.2 ± 19.8 years undergoing diagnostic endoscopy with 30 positive and 30 negative rapid urease test (RUT) and histology results for H. pylori infection were evaluated. H. pylori stool antigen test (HpSA) was measured in these patients and sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy for HpSA were calculated. Results: Among 31 positive HpSA results, 2 were negative in RUT and histology and among 29 negative HpSA results, 1 was positive in RUT and histology results. Sensitivity, specificity, PPV, NPV and accuracy for HpSA in diagnosing H. pylori infection were 96.67%, 93.33%, 93.55%, 96.55% and 95%, respectively. Conclusion: Although the sensitivity and specificity of the HpSA are evaluated in a relatively small sample size, these results showed that HpSA is a useful test in diagnosing H. pylori infection in patients with upper GI complaints.