Coexistence of granulomatous enteric inflammation and neoplasia in an adult sheep.

A 7-year-old dairy sheep suffering from chronic loss of weight without diarrhea or anorexia was euthanized after failing to respond to any treatment (antibiotic and antiparasitic). The main findings at the necropsy of this animal were multifocal miliary nodules in several organs, mainly in the Peyer's patches of the small intestine, and a segmental thickening of the jejunal wall. Histologic examination of the samples taken at the necropsy showed a multifocal chronic granulomatous inflammation, with mineralization and caseous necrosis at the core of the larger granulomas and scarce intrahistiocytic acid-fast bacilli consistent with a disseminated digestive tuberculosis. Polymerase chain reaction and bacteriological culture from these samples confirmed Mycobacterium avium subsp avium to be the etiologic agent of this infection. Histologically, the cause of the segmental thickening of the jejunal wall was found to be a small intestine adenocarcinoma, which in some areas coexisted with the granulomatous lesion.