Gastritis associated with Helicobacter-like organisms in baboons.

Subclinical gastritis was observed in 10 of 10 baboons (Papio spp.) from a toxicity study in a research facility. The lesions were similar in xenobiotic-treated and control animals, suggesting a spontaneous rather than chemical-induced disease. Histologic examination revealed lymphoplasmacytic gastritis in the antral mucosa. The fundic mucosa contained minor, scattered aggregates of lymphocytes and plasma cells. A Warthin-Starry silver stain and ultrastructural examination revealed numerous spiral-shaped bacteria morphologically resembling Helicobacter pylori in antral glands and numerous spiral-shaped bacteria morphologically consistent with H. heilmannii-like organisms in fundic glands. Polymerase chain reaction assay of paraffin-embedded antral and fundic tissue using primers for the urease gene and 16S ribosomal ribonucleic acid gene amplified deoxyribonucleic acid fragments with a high degree of sequence homology for H. pylori and H. heilmannii. This is the first report of gastritis associated with Helicobacter-like organisms in baboons.