Background: Diagnostic methods have recently been developed for detecting anti-Helicobacter pylori antibody in urine and H. pylori antigen in stool samples. Our aim was to evaluate the usefulness of noninvasive urine-based methods for the diagnosis of H. pylori infection.
Methods: The study subjects were 100 asymptomatic Japanese volunteers. We investigated the diagnostic efficacy of various noninvasive diagnostic methods; five serological tests (Immunis anti-pylori, HM-CAP, EIAgen Helicobacter pylori IgG, Helico G, and GAP-IgG), one test for antigen in stool (HpSA enzyme immunoassay [EIA]), and two tests for antibody in urine (Urinelisa and Rapirun) by using the urea breath test (UBT) as the gold standard.
Results: Fifty subjects were diagnosed as positive for H. pylori infection by the UBT. The serological tests showed good sensitivity, specificity, and accuracy. The diagnostic values of the feces-based test (HpSA EIA) were lower than that of the serological tests. The sensitivities of the two urine-based methods in frozen urine samples were markedly lower than those of the other tests. However, the use of unfrozen samples markedly improved the diagnostic accuracy of these urine-based tests, which was then superior to that of the feces-based method.
Conclusions: This study clearly showed that urine-based tests were useful for the diagnosis of H. pylori infection. However, the use of frozen urine samples was not appropriate for the detection of anti-H. pyloriantibody.