Accuracy of the [13C]-urea breath test in diagnosing Helicobacter pylori gastritis in pediatric patients

Background: The causal association between Helicobacter pylori (H. pylori) colonization of the gastric mucosa and gastritis is now well established Histologic examination of endoscopic biopsy specimens has long been regarded as the gold standard for diagnosis. However, the changes can be focal in nature and presence of the organism may be missed in nonsampled areas. The urea breath test, which uses a stable isotope, offers distinct advantages, in that it is noninvasive and measures the activity of the micro-organism. It thus represents a potentially invaluable tool in the initial diagnosis of the infection and in verifying its eradication. Methods: The study design was that of a prospective, blinded comparison of the [C-13]-urea breath test with histologic assessment of antral biopsy specimens using the Warthin-Starry stain, to diagnose H. pylori infection in a group of 79 consecutive pediatric patients. Results: Patients classified as negative by histology (n = 67) had breath C-13 enrichment of 0.97 +/- 0.07 delta parts per thousand (mean +/- SEM), with a range of -0.20 and 2.83 delta parts per thousand. In contrast, those with a positive histologic results (n = 12) had an enrichment of 25.41 +/- 5.01 delta parts per thousand (range, 3.43-58.80; p < 0.001). At the chosen cutoff point of 3 delta parts per thousand, the sensitivity and specificity as well as the positive and negative predictive values of the breath test were uniformly 100%. Conclusion: The [C-13]-urea breath test is a highly reliable, noninvasive method for the diagnosis of H. pylori gastritis in children and adolescents.