The frequency of lymphocytic gastritis in baboons.

BACKGROUND In 1985, two independent reports highlighted a novel subtype of chronic inflammation in the gastric mucosa, characterized by the intraepithelial lymphocytic infiltration (ILI) both in the surface and the foveolar epithelium. The disease, subsequently called lymphocytic gastritis (LG) is a rare form of gastritis (0.8%-1.6% of cases), with unclear pathogenesis. More recently, LG was recorded in pigs and in non-human primates. MATERIALS AND METHODS The frequency of LG (>25 lymphocytes/100 epithelial cells) was assessed in gastric specimens from 92 consecutive baboons, initially filed under the diagnosis of "gastritis". RESULTS LG was found in 13 (14%) out of the 92 animals. Helicobacter pylori was not found. DISCUSSION LG mirrors an immunological phenomenon at the surface-foveolar cell level elicited by an uncertain etiological factor. In similarity to humans with LG, no Helicobacter pylori were found in baboons with LG. The search for the lymphocyte-attracting protein contained in affected cells might bring forward an alternative therapy capable of abrogating the specific surface-foveolar cell-lymphotaxis present in LG. The baboon emerges as a possible animal model to study the agent(s) leading to LG.