Usefulness of Helicobacter pylori stool antigen test to monitor response to eradication treatment in children

Background: The monitoring of the results of eradication treatment is a cru cial step for patients with Helicobacter pylori gastritis. A non-invasive t est for H. pylori antigens in stools (HpSA) was recently validated for chil dren. Aim: To evaluate the accuracy of HpSA in monitoring eradication treatment i n children. Methods: In 60 children, H. pylori gastritis was diagnosed by endoscopy and the C-13-urea breath test. The children were treated and returned for a fo llow-up C-13-urea breath test 6 weeks after the end of treatment. Children were considered cured when the C-13-urea breath test was negative. Stool we re collected at baseline, and at 2 and 6 weeks. Stool antigens were measure d by HpSA. Results: According to C-13-urea breath test, 6 weeks after the end of treat ment 49 children were cured and 11 were still H. pylori-positive. The sensi tivity and specificity of HpSA on stools collected 2 weeks after therapy we re 100%. At 6 weeks specificity was 93.9 and sensitivity 100%. Results by v isual reading were concordant with the plate-reader in all but two cases at baseline. Conclusions: HpSA is accurate for monitoring treatment in children as early as 2 weeks after therapy, when information is most useful and unachievable with other tests. Results by visual reading are accurate, and this can mak e the test cheaper and more practical.