General Information: This organism was found to be linked to an increasing incidence of liver tumors in mouse colonies at the National Cancer Institute in 1992. Normally it resides in the lower intestines, but it can cause chronic hepatitis. This organism has a similar urease gene cluster and cytolethal distending toxin as compared to Helicobacter pylori, but lacks other virulence factors such as the vacuolating cytotoxin and the cag pathogenicity island. However, it does contain a pathogenicity island that encodes proteins similar to those found in a type IV secretion system. Causes liver disease. This genus consists of organisms that colonize the mucosal layer of the gastrointestinal tract or are found enterohepatically (in the liver). This species was associated with an increase in liver tumors. It can cause active chronic hepatitis and typhlitis (inflammation of a region at the beginning of the large intestine), hepatocellular tumors, and gastric bowel disease in various mice strains.