120Hepatic haematoma rupture in a Warmblood: a rare complication of hepatic AA amyloidosis M. Diekstall et al. Summary:A 15-year-old Warmblood gelding was referred to the clinic because of abdominal discomfort. One year before clinical evaluation, the horse presented with a mass in the back muscles that had first appeared 3 years prior. The mass, located in the caudal saddle position, was of an unknown cause and did not disturb the horse in any way. A calcification was recognized radiologically; however, treatment was not pursued because of high risk of poor wound healing and infection in this area. On the day of referral the horse was presenting signs of colic as a result of a haemoperitoneum following a ruptured haematoma in the liver, which was diagnosed by laparoscopy in the standing position. The horse was euthanized because of persistent, extensive haemorrhage from the unstoppable bleeding of the liver. At necropsy liver amyloidosis with subcapsular and intrahepatic haematoma was diagnosed. The calcified mass in the horse's back muscle was considered to be an old infected wound that could be the trigger for Amyloid-A (AA) amyloidosis. To the author's knowledge, this condition has not yet been described in horses. Citation: Diekstall M., Veh J., Rijkenhuizen A. B. M. (2019) Hepatic haematoma rupture in a Warmblood: a rare complication of hepatic AA amyloidosis. Pferdeheilkunde 35, 120-125;