Canine lymphocytic plasmocytic enteritis: an immunopathological investigation of intestinal plasma cells.

The numbers of IgA-, IgG- and IgM-containing plasma cells in the lamina propria of duodenum, jejunum, ileum, and coecum were quantitated in 3 patients suffering from lymphocytic plasmacytic enteritis and 3 normal control dogs. A great increase was found in all 3 types of plasma cells and at all levels of the intestinal tract. Especially the IgG-containing cells showed a remarkable increase particularly in 2 patients. The possible reasons for these heavy infiltrations of immunologically competent cells are discussed, and chronic antigenic stimulations of food origin is suggested.