MYOSITIS OSSIFICANS TRAUMATICA IN A VAMPIRE BAT (DESMODUS ROTUNDUS).

A 15-yr-old sexually intact female vampire bat ( Desmodus rotundus ) was diagnosed with myositis ossificans traumatica of the abdominal wall. The bat presented with a large ulcerated firm mass along the abdomen. Radiographs and cytology were performed, followed by surgical exploration. The mass was determined to be nonresectable and the bat was euthanized. Histopathology showed severe necrotizing, degenerative, and pyogranulomatous myositis with osseous and cartilaginous metaplasia, fibrosis, and ulceration, which were consistent with myositis ossificans traumatica. Myositis ossificans traumatica is commonly associated with previous trauma to skeletal muscle. Two years prior, this bat had an emergency Caesarian section at this site, which was postulated to elicit a marked tissue response leading to this condition. Myositis ossificans traumatica is infrequently reported in humans, dogs, cats, pigs, and horses. To the author's knowledge, this is the first report of this condition in a bat.