At the time of this writing, a total of 15 species, 35 individual animals, have had gastric biopsies performed opportunistically during medical procedures. None of the animals were exhibiting signs of gastritis clinically at the time of endoscopy. All animals were intubated and anesthetized with isoflurane (Attane, Minrad, Inc., Buffalo, NY, USA) and positioned in left lateral recumbency. A survey exam of the esophagus and stomach was performed initially and then four gastric biopsies, primarily from the fundic region, were obtained using an oval cup forceps with a spike. All biopsy samples were placed in 10% neutral buffered formalin and submitted to the same diagnostic laboratory (IDEXX Laboratory, Westminster, CO, USA) and were examined by the same pathologist. Each biopsy sample was sectioned at 5–6 µm thick and stained with hematoxylin and eosin, and then evaluated for pathologic changes via light microscopy, as well as for the presence of Spirillum bacteria. If no bacteria were observed under light microscopy Warthin-Starry silver stain was used to determine if Spirillum bacteria were present.
Results were grouped in one of four ways:
1. Normal tissue microscopically and stains negative for Spirillum bacteria.
2. Normal tissue microscopically, stains positive for Spirillum bacteria, but no inflammatory infiltrates seen (incidental finding).
3. Gastritis microscopically, stains positive for Spirillum bacteria, and inflammatory infiltrates seen.
4. Gastritis microscopically and stains negative for Spirillum bacteria.
Animals with gastritis were described as superficial type, lymphoplasmacytic and eosinophilic variant, widespread, chronic. Animals that had incidental findings for Helicobacter were described as Spirillum bacteria associated with superficial mucosal surface and glandular elements, but not associated with inflammation. Results from the study showed 46% (n=16) in group 1, 20% (n=7) in group 2, 32% (n=11) in group 3, and 2% (n=1) in group 4. Based on these results Helicobacter can be a common pathologic finding without being a primary cause for gastritis. Interpretation of results from gastric biopsies should be evaluated with clinical signs before instituting therapy and additional tests may be indicated to rule out other potential causes for gastritis.