Helicobacter felis infection in dogs: Effect on gastric structure and function

The relationship of Helicobacter felis, an organism that is observed in the stomachs of dogs, to gastric disease in dogs is unclear. The objective of this study was to determine if Helicobacter felis infection alters gastric morphology and gastric secretory function in dogs. Five specific-pathogen-f ree (SPF), Helicobacter-free Beagle dogs were examined before and for 26 we eks after inoculation with H. felis (ATCC 49179). Three SPF uninfected dogs served as controls. All five dogs became colonized by H. felis as determin ed by urease activity, histopathology, polymerase chain reaction, and trans mission electron microscopic examination of serial gastric biopsies. The de gree of colonization ranged from <1 organism/400x field to >10 organisms/40 0x field. The fundus, body, and cardia were most heavily colonized. Evaluat ion of gastric biopsies showed mild gastric inflammation and lymphoid folli cles in both infected and uninfected dogs. There was no correlation between the number of organisms observed and the degree of gastric inflammation or number of lymphoid follicles. The gastric secretory axis, assessed by fast ing and meal-stimulated plasma gastrin, mucosal gastrin and somatostatin im munoreactivity, fasting gastric pH, and pentagastrin-stimulated gastric aci d secretion, was similar in both infected and uninfected dogs. Easting gast ric pH was not a reliable indicator of gastric secretory function. These fi ndings suggest that H. felis may not be a gastric pathogen in dogs. However , the density of colonization and limited duration of infection should be c onsidered when interpreting these findings.