Evaluation of a Helicobacter pylori stool antigen test for the diagnosis and follow-up of infections in children

The aim of this study was to evaluate the performance of a newly developed enzyme immunoassay kit (HpSA) for detecting Helicobacter pylori antigens in the stool of children. This study was comprised of 58 children referred to various endoscopy units for evaluation of gastrointestinal symptoms and up per gastroduodenal endoscopy and 11 children for post-therapy follow-up. In the first group, 23 children were diagnosed as positive for Helicobacter p ylori using bacteriological and/or histological methods. Stool antigens wer e detected in 20 of these positive patients, for a sensitivity of 86.9% and a negative predictive value of 91.9%. Since only one false-positive reacti on was observed with the HpSA kit, the specificity was 97.1% and the positi ve predictive value 95.2%. Results obtained for post-therapy follow-up were also promising. The HpSA assays were negative for the eight children whose infections were eradicated after therapy, and a positive result was obtain ed for two of three patients who had a persistent infection.