Comparison of noninvasive diagnostic tests for Helicobacter pylori infection.

OBJECTIVES Since the (13)C-urea breath test (UBT) has become a highly reliable method for the noninvasive diagnosis of Helicobacter pylori infection, this study was performed in order to compare the sensitivity, specificity and accuracy among noninvasive tests including capsule UBT, conventional UBT and serology in the diagnosis of H. pylori infection. PATIENTS AND METHODS One hundred patients received capsule UBT, conventional UBT and gave blood samples for the diagnosis of H. pylori infection. Upper gastrointestinal endoscopy was performed in all patients. H. pylori infection was defined as the presence of a positive culture or positive results of both histology and rapid urease test (CLO test). McNemar's test was used to determine the significance of differences among capsule UBT, conventional UBT and serology. Differences were considered significant at p < 0.05. RESULTS According to the predefined criteria, the sensitivity, specificity, positive predictive value and negative predictive value of capsule UBT, conventional UBT and serology was 100, 95.7, 96.4 and 100%; 100, 85.1, 88.3 and 100%, and 90.6, 85.1, 82.7 and 88.9%, respectively. The accuracy of capsule UBT was higher than that of conventional UBT and serology (98 vs. 93 and 88%, respectively). Capsule UBT had a similar ability for the detection of H. pylori infection compared with conventional UBT and serology (McNemar's test, p > 0.05). CONCLUSIONS According to our study, capsule UBT was highly accurate compared with other noninvasive tests including conventional UBT and serology. It could become a good alternative to endoscopy for the diagnosis of H. pylori infection.