Diagnostic accuracy of non-invasive tests for helicobacter pylori infection in children: A multicenter retrospective study by SIGENP

Background: Helicobacter pylori (H. pylori) infection remains prevalent in children, with significant clinical implications. While endoscopy with biopsy is the gold standard for diagnosis, non-invasive tests such as the stool antigen test (SAT) and urea breath test (UBT) may offer alternatives. Objectives: To assess the diagnostic accuracy of SAT and UBT in children with suspected H. pylori infection and identify clinical predictors of infection. Methods: This retrospective multicenter study included pediatric patients undergoing endoscopy for suspected H. pylori across six Italian centers. Histological analysis served as the reference standard. Diagnostic metrics of SAT and UBT were calculated. Demographic and clinical factors were analyzed to identify independent predictors. Results: Of 256 patients, 150 (58.6 %) had confirmed infection. SAT showed higher sensitivity [94 % (95 % CI: 0.87–0.97)] than UBT [87 % (CI: 0.64–0.98)] but lower specificity [55 % vs 67 %], with lower PPV (64 % vs 78 %) and higher NPV (91 % vs 80 %). Independent predictors for H. pylori infection included family history [OR 4.4], positive SAT [OR 16.29], and non-Caucasian ethnicity [OR 4.3]. Conclusions: SAT demonstrates high sensitivity and NPV, supporting its role as a screening tool. In children without alarm symptoms, a negative SAT may safely exclude infection and help avoid unnecessary endoscopy.