Functional intestinal hypomotility in association with neuronal damage in a dog.

A young, crossbred dog with a 13-month history of progressively worsening, recurrent episodes of vomiting, anorexia, depression and dehydration was diagnosed as having a functional hypomotility disorder of the small intestines. During hospitalisation, the dog's condition improved only when total parenteral nutrition was administered. When fed orally, the dog developed severe gastric dilatation. Intestinal motility was minimal, but was induced by neostigmine. Post mortem findings included dilatation of the duodenum and progressive narrowing of the small bowel up to the ileum. Histopathology revealed various grades of neuronal degeneration and necrosis of the myenteric plexuses throughout the small intestine. Microscopic changes resembled those reported in dysautonomia, but were limited to small intestinal myenteric plexuses. A localised congenital neuronal defect causing a lack of parasympathetic tone is suspected.