Alimentary TractDual-priming oligonucleotide-based multiplex PCR using tissue samples from the rapid urease test kit for the detection of Helicobacter pylori in bleeding peptic ulcers

BackgroundIn patients with peptic ulcer bleeding (PUB), diagnostic tests for Helicobacter pylori (H. pylori) infection have low sensitivity. The aim of our study was to investigate the diagnostic yield of dual-priming oligonucleotide-based multiplex (DPO)-PCR using tissue samples from the rapid urease test (RUT, CLO®test) kit in patients with PUB.MethodsWe prospectively enrolled patients with PUB. During second-look endoscopy, gastric biopsy specimens for histology and RUT were obtained from a total of 170 patients. DPO-PCR tests were performed on tissue samples obtained from the CLO®test kit. If testing for H. pylori was negative, endoscopy with re-biopsy was performed 8 weeks after the bleeding episode.ResultsH. pylori-associated bleeding was confirmed in 64.1% (109/170) of the patients. At the bleeding episode, the diagnostic sensitivities of RUT, histology, and DPO-PCR test were 47.7% (52/109), 71.6% (78/109) and 97.2% (106/109), respectively (p < 0.01). The specificity of the DPO-PCR test was 91.8% (56/61). The positive predictive value (PPV) of the DPO-PCR test was 95.5% (106/111), and its negative predictive value (NPV) was 94.9% (56/59).ConclusionsIn patients with PUB, the DPO-PCR test could be a useful diagnostic tool for H. pylori infection. Particularly given a negative RUT result, subsequent DPO-PCR testing of tissue samples from the CLO®test kit could be of considerable benefit.