Objective: Reliable non-invasive methods for detection of Helicobacter
Pylori (H. pylori) infection are required to investigate the
incidence, transmission, and clearance of infection in childhood.
Detecting bacterial antigens in stool offer an alternative noninvasive
diagnostic test. However its accuracy in developing countries is not
well established. The aim of this study was to evaluate the performance
of stool antigen test for H pylori in Iranian children with recurrent
abdominal pain necessitating endoscopy. Methods: One hundred three
children enrolled in this study. Endoscopy and biopsy was done on all
patients providing a criterion standard for validation of the H. pylori
stool antigen (HpSA) tests. The presence of H. pylori organisms in
stool was determined by an enzyme-linked immunosorbent assay using a
commercially available polyclonal antibody. HpSA sensitivity,
specificity, and positive and negative likelihood ratios were
determined with reference to the results of cultures of gastric biopsy.
Findings: Of the 103 children tested 41 (39.8%) and 39 (37.8%) were
positive for H. pylori according to the results of cultures of gastric
biopsy and HpSA, respectively. The sensitivity, specificity, and
positive and negative likelihood ratios of HpSA were found to be 85%,
93%, 89.7%, and 90%, respectively. Conclusion: In this pilot study, a
low-cost and rapid diagnostic technique, stool antigen test proved to
be highly sensitive and specific for detecting H pylori infection in
children with recurrent abdominal pain. Our results are comparable to
those reported elsewhere in children and demonstrate that the HpSA test
can replace endoscopy and biopsy for detecting H. pylori infection