diagnostic accuracy of polyclonal stool antigen for detection of helicobacter pylori infection in children

introduction: helicobacter pylori infection has various clinical features. one of the most common presentations of this infection is upper abdominal pain. complications such as gastritis, gastric ulcer, gastric carcinoma and malt lymphoma mandate early diagnosis of h.p infection by a low cost and non invasive manner. the aim of this study was to evaluate the diagnostic role of h.p stool antigen detection as a simple and non invasive method for diagnosis of this infection.   materials and methods: upper endoscopy with gastric biopsy was done on all patients between 6 months to 18 years old with upper abdominal pain. stool test was done by polyclonal anti-h.p antibody. results of stool test were compared with results of rut and histologic examination   results: overall 110 patients (57 boys,53 girls) were studied, 32 patients were helicobacter pylori positive and 78 patients were helicobacter pylori negative based on rut and histologic examination. stool antigen testing was positive for 39 patients. sensitivity and specificity of stool ag were 100% and 91% respectively.   conclusion: stool ag test has high sensitivity and negatity predictive value for diagnosis of helicobacter pylori infection.   keywords: helicobacter pylori, sensitivity, stool antigen test, specificity.