Detection of <i>Helicobacter hepaticus</i> in Human Bile Samples of Patients with Biliary Disease

<jats:title>Abstract</jats:title><jats:p><jats:bold>Background: </jats:bold> Since the discovery of <jats:italic>Helicobacter pylori</jats:italic>, various enterohepatic <jats:italic>Helicobacter</jats:italic> spices have been detected in the guts of humans and animals. Some enterohepatic Helicobacters have been associated with inflammatory bowel disease or liver disease in mice. However the association of these bacteria with human diseases remains unknown.</jats:p><jats:p><jats:bold>Materials and Methods: </jats:bold> We collected 126 bile samples from patients with cholelithiasis, cholecystitis, gallbladder polyp, and other nonbiliary diseases. Samples were screened for the presence of enterohepatic <jats:italic>Helicobacter</jats:italic> spp. using cultures, nested PCR, or in situ hybridization. We tested for antibodies to <jats:italic>H. pylori</jats:italic> and <jats:italic>H. hepaticus</jats:italic> by Western blot analysis.</jats:p><jats:p><jats:bold>Results: </jats:bold> Attempts at cultivation were unsuccessful. However, <jats:italic>H. hepaticus</jats:italic> was detected in bile samples with nested PCR whereas <jats:italic>H. bilis</jats:italic> was not. <jats:italic>Helicobacter hepaticus</jats:italic> in the bile was confirmed by in situ hybridization, but <jats:italic>H. hepaticus</jats:italic> from bile samples was coccoid in appearance. We detected immunoglobulin G antibodies to <jats:italic>H. hepaticus</jats:italic> in bile samples by Western blotting. <jats:italic>Helicobacter hepaticus</jats:italic> was detected in 40 (32%) of total 126 samples as <jats:italic>H. hepaticus</jats:italic> positive if at least one of the three methods with nested PCR, in situ, or Western blotting. Patients with cholelithiasis (41%) and cholecystitis with gastric cancer (36%) had significantly higher (<jats:italic>p</jats:italic> = .029) prevalence of <jats:italic>H. hepaticus</jats:italic> infection than samples from patients with other diseases.</jats:p><jats:p><jats:bold>Conclusion: </jats:bold> <jats:italic>Helicobacter hepaticus</jats:italic> may closely associate with diseases of the liver and biliary tract in humans.</jats:p>