Gastric Function in Dogs with Naturally Acquired GastricHelicobacterspp. Infection

Abstract

The association ofHelicobacter pyloriwith gastritis, peptic ulcers, and gastric neoplasia has led to fundamental changes in the understanding of gastric disease in humans. The relationship ofHelicobacterspp. infection to gastric disease in dogs is unclear. The objective of this study was to determine ifHelicobacterinfection affects the gastric secretory axis of dogs. Eight Beagle dogs with naturally acquiredHelicobacterspp. infection were studied before and after (4 and 29 days) the attempted eradication ofHelicobacterspp. with a combination of amoxicillin, metronidazole, and famotidine (AMF). Six specific‐pathogen‐free,Helico‐bacter‐freeBeagle dogs served as controls. The electron microscopic appearance of spiral organisms in infected dogs indicated coinfection withHelicobacter felis‐ andH bizzozeronii‐liks organisms. Unstimulated gastric pH and fasting, postprandial, and bombesin‐stimulated plasma gastrin were similar in both infected and uninfected dogs, although a trend (P= .09) toward higher meal‐stimulated gastrin was observed in infected dogs at 60 minutes. Pentagastrin‐stimulated maximal acid output (mmol HC1/ kg0 75/hour) and titratable acidity (mmol HCl/mL) were similar in both infected and uninfected dogs, but gastric pH during maximal acid output was lower (P< .01) in uninfected dogs. Mild gastric inflammation was present in both infected and uninfected dogs. Gastric spiral organisms were undetectable in 6/8 infected dogs 4 days after AMF but had recurred in 8/8 dogs 29 days after AMF. Analysis of gastric DNA withHelicobacter‐specificprimers indicated persistence ofHelicobacterDNA at 4 and 29 days after antibiotic therapy. Acid secretion, plasma gastrin, and mucosal inflammation were not affected by the transient suppression ofHelicobacterspp. by AMF. These findings suggest that gastric secretory function in dogs is not markedly perturbed by naturally acquiredHelicobacterspp. infection and that treatment with amoxicillin, metronidazole, and famotidine causes suppression rather than eradication of gastricHelicobacterspp. in dogs.