Presumed successful steroid therapy for suspected thrombotic microangiopathy in a dog

A 2-year-old castrated male Pembroke Welsh corgi dog was presented to the referring veterinarian because of acute onset of vomiting and hyporexia. Despite conservative treatment with intravenous fluids, antiemetics, antibiotics, and antioxidants, the dog rapidly deteriorated, with development of severe pigmenturia and icterus over 24 to 48 h, respectively, prompting referral. A thrombotic microangiopathy (TMA) characterized by nonimmune-mediated hemolytic anemia, thrombocytopenia, and acute kidney injury (AKI), suspected to be from hemolytic uremic syndrome not associated with known prodromal diarrhea, was diagnosed. This is a rarely described disorder in dogs and, unlike those in most previous reports, this dog survived with supportive care for AKI and a short tapering course of glucocorticoids for refractory thrombocytopenia. Steroids have been reported for managing certain TMA syndromes in humans but not in animals. The dog in this case made a full recovery, with no reported relapse over 1 y. Key clinical message: Thrombotic microangiopathy is characterized by nonimmune-mediated hemolytic anemia, thrombocytopenia, and AKI. Corticosteroids may be beneficial for treating canine TMA, based on successful recovery in this rare case of non-diarrheal hemolytic uremic syndrome.