Quantitative Assessment of TPE Antibody Removal and Clinical Response in a Dog With Severe Type III Hypersensitivity Reaction and AKI due to Human Albumin Administration

Objective To describe the successful removal of antihuman albumin antibodies by therapeutic plasma exchange (TPE) in a dog with signs of delayed type III hypersensitivity reaction (tIIIHr), including acute kidney injury (AKI), secondary to administration of human serum albumin (HSA). Case Summary A 9‐month‐old dog was presented with an infected wound and treated with vacuum‐assisted closure. A 28‐h infusion of 20% HSA was administered to the dog postoperatively to treat persistent hypoalbuminemia during hospitalization. Seventeen days later, the dog returned for acute periorbital swelling. Clinical signs improved after standard treatment for a nonspecific allergic reaction. Five days later, the dog developed persistent vomiting, generalized subcutaneous edema, and ecchymoses on the ventral abdomen. Severe azotemia with proteinuria led to the diagnosis of acute glomerulonephritis. A delayed tIIIHr secondary to HSA administration was suspected. Two sessions of TPE were performed on consecutive days. Complete resolution of clinical signs, including azotemia, occurred after the second TPE session, and the dog was discharged 5 days later in good clinical condition. The urine protein:creatinine ratio normalized within 2 weeks of TPE. Antihuman albumin antibody concentrations were measured by indirect ELISA in the patient's plasma and in the plasma removed by TPE. New or Unique Information For the first time, antihuman albumin antibodies have been measured before and after treatment with TPE in a dog with clinical signs of delayed tIIIHr, demonstrating the effective removal of antibodies. Based on these findings, TPE could be considered for the treatment of severe tIIIHr after xenotransfusion.