Comparison of gastric and duodenal lesions in dogs and cats with and without lymphocytic-plasmacytic enteritis.

OBJECTIVE--To compare histologic lesions in the stomach and duodenum of dogs and cats with and without lymphocytic-plasmacytic enteritis (LPE). DESIGN--Case-control study. ANIMALS--20 clinically normal dogs, 40 dogs with LPE, 10 clinically normal cats, and 20 cats with LPE. RESULTS--Unevenness of the mucosal surface was detected in the stomach of 4 of the 20 (20%) clinically normal dogs and 10 of the 40 (25%) dogs with LPE. Mucosal friability was detected in the duodenum of 16 (40%) of the dogs with LPE and 10 of the 20 (50%) cats with LPE. Histologically, clinically normal dogs and dogs with LPE had various degrees of fibrosis in the gastric lamina propria. All of the clinically normal cats and the cats with LPE had slight gastric fibrosis. Clinically normal cats had infiltrates of inflammatory cells similar to those seen in the clinically normal dogs. Significantly more plasma cells and lymphocytes were seen in the duodenal lamina propria of dogs and cats with LPE than in the duodenal lamina propria of clinically normal animals. CLINICAL IMPLICATIONS--LPE should be diagnosed by counting the number of inflammatory cells in the duodenal lamina propria and then comparing that number with the number seen in clinically normal animals.