Helicobacter pylori Eradication Rate Using Stool Antigen Test in Vietnamese Children: A Prospective Multicenter Study

Abstract

Objectives:This study assessed the diagnostic value of a monoclonal immunoassay stool antigen test (HpSA) forHelicobacter pylori (H. pylori) infection and the eradication outcomes.Methods:Children undergoing digestive endoscopy at 2 Children’s Hospitals in Ho Chi Minh City were recruited. Treatment was offered toH. pylori-infected children. Stool samples were collected on the same day as the endoscopy procedure and after 6 weeks post-treatment for HpSA. Diagnostic value and optimal cutoff of HpSA were assessed using biopsy-based tests as the gold standard. Eradication was defined as a negative HpSA post-treatment. Ethical approval was obtained, and informed consent was signed by the participants.Results:In total, 394 patients participated in the study. The most common symptoms were epigastric pain (74.6%) and vomiting (37.3%).H. pyloristatus was positive in 78% of patients (306/394), doubtful in 10.1%, and negative in 12.2%. HpSA was positive in 73.2% (142/194). Excluding doubtful infections, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of HpSA were 87.4%, 95.2%, 99.2%, 51.3%, and 88.4%, respectively. The optimal cutoff value of 0.148 provided similar accuracy to the recommended cutoff. The eradication rate was 56.1% in per-protocol analysis and 27.9% in intention-to-treat analysis. Treatment success was higher in boys, but lower among malnourished children and those infected withcagA+strains.Conclusions:The HpSA is reliable for identifyingH. pyloriinfection in epidemiological studies and assessing eradication outcomes. The low eradication rate highlights the need for an appropriate intervention strategy in Vietnamese children.