Accuracy of Stool Antigen Test in the Diagnosis of Helicobacter pylori Infection in the Dominican Republic

Introduction: Helicobacter pylori is a well-studied infectious agent due to its pathogenic potential for peptic ulcers and gastric cancer. It has a high prevalence worldwide and has several diagnostic methods, both invasive and non-invasive. It is important to address the diagnostic efficacy of these tests, as the data vary by location and the specific population in which they are used. Therefore, an effective testing method should be obtained, evaluating the possibility of substantially reducing invasive procedures and, therefore, associated costs. Objective: This study proposes to define the diagnostic accuracy of the stool antigen test for H. pylori infection in the Dominican Republic. Methods: An observational, retrospective, and cross-sectional study was conducted. The results of the stool antigen test for H. pylori infection were compared with the results of the gastric biopsy, as a gold standard test. Patients over 18 years of age with an indication for endoscopy due to suspicion of H. pylori infection, who attended the gastroenterology clinic in 2021, were included in the study. Results: It was shown that the stool antigen test for H. pylori infection has a 61.54% sensitivity and 59.65% specificity. According to the study population, the positive predictive value (PPV) was 67.60% and the negative predictive value (NPV) was 53.13%. Conclusion: Low numbers of both sensitivity and specificity were determined, which is why it is pertinent to study alternative non-invasive methods. However, it is important to assess the antibiotic exposure of the study population, since the diagnostic accuracy of the stool test can be influenced by this factor.