Helicobacter Species and Their Association with Gastric Pathology in a Cohort of Dogs with Chronic Gastrointestinal Signs

SIMPLE SUMMARY: Helicobacter spp. represent spiral-shaped Gram-negative bacteria that can live in the acidic environment of the stomach. While their association with peptic ulcers and gastric neoplasia in people has been clearly documented, their pathogenic potential in dogs is less well defined. Helicobacter pylori, the most prevalent Helicobacter infecting people, does not seem to represent a significant problem in small animals. The aims of this study were to determine the prevalence of individual gastric Helicobacter species in dogs with chronic gastrointestinal signs, their association with gastric lesions, and to compare diagnostic techniques used to detect Helicobacter infection in dogs. ABSTRACT: Prevalence of individual Helicobacter species, data evaluating their association with gastric pathology and comparison of accuracy of diagnostic techniques are limited. The aims of this study were to determine the prevalence of gastric Helicobacter species, their association with gastric pathology, and to compare diagnostic techniques. Gastric biopsies from 84 privately-owned dogs with chronic gastrointestinal signs were obtained endoscopically. Helicobacters were detected using PCR, cytology, urease test, and histopathology. PCR detected helicobacters in 71.4% of dogs. Helicobacter heilmannii sensu stricto (s.s.) was the predominant species. Mixed infection was detected in 40% of PCR positive dogs. Gastritis was diagnosed in 38.5% of Helicobacter positive and 47.4% of Helicobacter negative dogs. Mono-infection was associated with 2.4 times increased odds of having more severe inflammation compared to mixed infection. Erosions and ulcers were common endoscopic lesions. Cytology had sensitivity/specificity of 88.3/91.7%. Association between infection and lymphoid follicular hyperplasia was demonstrated.