Comparison of Noninvasive Diagnostic Tests for Helicobacter pylori Infection
Medical Principles and Practice
Introduction This study was performed in order to compare the sensitivity, specificity and accuracy among noninvasive tests including capsule 13 C-urea breath test (UBT), conventional UBT and serology in the diagnosis of Helicobacter pylori infection. H . pylori infection can be diagnosed by invasive and noninvasive techniques. Invasive methods require endoscopy-and biopsy-based tests, including microbiological culture, histology, rapid urease test (CLO test) and polymerase chain reaction.
... hain reaction. Noninvasive tests include serology, stool antigen test and breath test. The choice of a diagnostic test should depend on the clinical circumstances, sensitivity and specificity of the tests, and the cost-effectiveness of the testing strategy. According to our prior articles [1, 2] , the sensitivity of culture, histology and CLO test was 77.8-94.4, 88.9-90.9 and 82.1-94.4%, respectively, and the specificity was 100, 90.6-100 and 95.5-96.9%, respectively. The overall accuracy of serological assays average 78%  . The sensitivity and specificity of UBT have been shown to range from 90 to 100%, compared with biopsy-based tests for H . pylori Abstract 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 1 0.05). Conclusions: