Gastritis in dogs: are Helicobacter spp. (Gastric Helicobacter-Like Organisms, GHLO) pathogenic?

The pathogenicity of helicobacter spp. or Gastric Helicobacter-like Organisms (GHLO) for the development of gastritis in the dog is unclear. Representative data are not available, since GHLO-species differentiation can still only be done by electronmicroscopy and microbiology and not by routine laboratory investigations, e.g. urease assay, histopathology or immunohistochemistry. In the present study, we have investigated dogs with gastritis and gastroenteritis, respectively, for infection with GHLO and inflammatory reactions clinically and by biopsy-specimens from the whole gastrointestinal tract. Other enteropathies and extra-intestinal diseases were rouled out clinically and serologically. The main observations were that (1) GHLO-infections occurred in dogs with gastritis as much as in dogs without gastritis; (2) there was no relation between the number of GHLO and the degree, quality and distribution of inflammatory reactions in diseased dogs; (3) gastritis was often associated with enteritis in dogs without clinical evidence. To discriminate possible GHLO-induced gastritis and gastritis associated with systemic inflammatory bower disease, endoscopy/biopsy of the whole gastrointestinal tract is recommended.