Massive transfusion of incompatible red blood cells: A case report demonstrating the benefits of a regional patient alloantibody registry and prompt automated red cell exchange.

Background: Emergent transfusion is carried out without standard pre-transfusion serologic testing to detect alloantibodies in patient plasma. Transfusion of red blood cells positive for antigens incompatible with a patient's current or historical alloantibodies risks acute and delayed hemolysis, which may be fatal. Symptomatic and prophylactic treatment of hemolysis secondary to transfusion of incompatible non-ABO antigens using automated red cell exchange has been rarely reported.

Case report: A 77-year-old female with extensive hemorrhage from a femoral artery pseudoaneurysm received a massive transfusion of uncrossmatched blood. Although subsequent testing of a pre-transfusion sample was inconclusive, a search of a patient alloantibody registry showed a history of anti-E, anti-Fya, and anti-Jk(a) antibodies, which were subsequently confirmed and proven incompatible with all 10 transfused red blood cell units in various combinations. Prior to the completion of repeat serologic testing, the historical alloantibody profile was used to allocate antigen-negative units for automated red cell exchange to treat progressive transfusion-related hemolysis. Treatment was completed without complications, and hemolysis gradually resolved without progression of hemodynamic instability.

Conclusions: This case demonstrates successful automated red cell exchange following massive transfusion of red blood cells including a combination of three clinically significant incompatible antigens. Access to a patient alloantibody registry facilitates timely evaluation and management of transfusion-associated adverse events which may otherwise be unavoidable.