[Latest advances in non-pylori Helicobacter species].

The genus Helicobacter presently comprises 32 validly named species. Helicobacter equorum, Helicobacter baculiformis and Helicobacter suis were recognized as new species in 2007 and 2008. Non-pylori Helicobacter species are occasionally isolated from human clinical specimens, though their natural hosts are mammals other than human and birds. It remains unclear whether they are associated with human diseases. 'Helicobacter heilmannii' causes human chronic gastritis. Several reports suggest that Helicobacter hepaticus and Helicobacter bilis are associated with human hepatic and biliary disorders, respectively. Non-pylori Helicobacter species are occasionally isolated from clinical specimens of immunocompromised hosts. These cases suggest that they are important opportunistic pathogens.