Therapeutic Plasma Exchange for Acute Hemolytic Anemia in a Dog With Immune-Mediated Thrombocytopenia Following Administration of Human Intravenous Immunoglobulin.

Objective: To describe therapeutic plasma exchange as treatment for severe acute hemolytic anemia resulting from human intravenous immunoglobulin (hIVIG) in a dog with primary immune-mediated thrombocytopenia (IMTP).

Case summary: A 4-year-old neutered female Pomeranian with a recent diagnosis of IMTP presented with a potential relapse. Management with initial medications, including prednisolone and mycophenolate mofetil, was unsuccessful; therefore, the dog was administered hIVIG. Fifteen hours later, the patient developed an adverse reaction including vomiting and dark urine. Laboratory and clinical evidence of acute hemolysis was detected, including decreased hematocrit, hemoglobinemia from gross identification of serum, elevated total bilirubin, hemoglobinuria, and reticulocytosis. Supportive care for the dog was ineffective, and due to an adverse reaction characterized by severe salivation, a blood transfusion could not be done. Therapeutic plasma exchange (TPE) was performed to eliminate the causative agents, controlling the hemolytic anemia. After TPE, immunosuppressants were prescribed to treat the IMTP, which resolved 15 days later. At the time of this report, the patient is alive with no complications or clinical signs of IMTP.

Unique information provided: Acute hemolytic anemia caused by hIVIG is a rare adverse reaction in veterinary medicine. This is the first report of TPE being used to successfully treat this potentially life-threatening condition.