A modified Sydney system for the diagnosis of chronic gastritis in dogs

Background: The Sydney system for assessing inflammatory lesions in the gastric mucosa is based on endoscopic and histological examinations. This study aimed to apply the Sydney system to diagnose gastritis in dogs. The study also compared the results of endoscopic and histological examinations conducted on gastric mucosal biopsy specimens. A total of 56 dogs with chronic vomiting were analyzed in the study. The physical appearance of the gastric mucosa was assessed through endoscopic examination, while the severity of the gastric inflammation, inflammation activity, glandular atrophy, and intestinal metaplasia were assessed by histopathological examination.

Results: The endoscopic examination confirmed the presence of inflammatory lesions affecting the gastric corpus and pylorus in all the dogs, although the severity of these lesions differed between the individuals. Reflux gastritis was the most commonly observed gastric inflammation. In the histopathological examination of the gastric mucosal samples, inflammatory lesions were found in the gastric corpus of 53 dogs, while 55 dogs had lesions in the pylorus. This corresponds to a 96.4% agreement between the methods.

Conclusions: The Sydney system is a useful tool for macroscopic and microscopic assessment of changes in the gastric mucosa as it enables the determination of inflammation type and severity, which helps the canine gastroenterologists to reliably compare the results of the tests performed in different facilities. Besides, the use of the Sydney system in diagnosing lesions facilitates the selection and effective monitoring of treatment. However, despite a high rate of agreement between the results of endoscopic and histopathological examinations, it is recommended to use both these methods for the assessment of the gastric mucosa in dogs.

Keywords: Dogs; Endoscopic examination; Gastritis; Histopathological examination; Sydney system.