title: Successful use of eculizumab for treatment of an acute hemolytic reaction after ABO-incompatible red blood cell transfusion.
abstract: BACKGROUND
  Transfusion of ABO major-incompatible red blood cells (RBCs) can activate the complement system and can cause severe and even lethal acute hemolytic reactions. The activation of the complement system with formation of C3a and C5a (anaphylatoxins) and the release of hemoglobin from the lysed RBCs are thought to mediate clinical signs like fever, hypotension, pain, and acute renal failure. Therapeutic inhibition of the complement cascade in case of ABO-incompatible RBC transfusion would be desirable to ameliorate the signs and symptoms and to improve the outcome of the reaction.
  
  
  METHODS
  A patient with blood group B was erroneously transfused with a unit of group A2 RBCs. Within 1 hour after transfusion she received eculizumab, a monoclonal antibody that binds to the complement component C5 and blocks its cleavage. Clinical and immunohematologic observations are reported here.
  
  
  RESULTS
  Hemoglobinemia and hemoglobinuria were present for several hours after transfusion, but she developed no hypotension, no renal failure, and no disseminated intravascular coagulation. As shown by flow cytometry, group A cells survived in the peripheral blood for more than 75 days. No immunoglobulin G was detectable by column agglutination technique on these cells.
  
  
  CONCLUSIONS
  A low isoagglutinin titer and blood group A2 of the erroneously transfused cells most likely were the reason for the absence of clinical signs during and immediately after the ABO-incompatible transfusion. In the further course, eculizumab successfully protected the incompatible RBCs from hemolysis for several weeks.
authors.affiliation: Institute of Clinical Transfusion Medicine and Immunogenetics Ulm, German Red Cross Blood Service Baden-Württemberg-Hessen, Institute of Transfusion Medicine, University of Ulm, Ulm, Germany.
authors.forename: Christof
authors.initials: C
authors.lastname: Weinstock
authors.forename: Robert
authors.initials: R
authors.lastname: Möhle
authors.forename: Christiane
authors.initials: C
authors.lastname: Dorn
authors.forename: Katja
authors.initials: K
authors.lastname: Weisel
authors.forename: Britta
authors.initials: B
authors.lastname: Höchsmann
authors.forename: Hubert
authors.initials: H
authors.lastname: Schrezenmeier
authors.forename: Lothar
authors.initials: L
authors.lastname: Kanz
mesh_terms: D000017:ABO Blood-Group System / Q000276:immunology*; D000208:Acute Disease; D000743:Anemia, Hemolytic / Q000188:drug therapy* / Q000209:etiology; D061067:Antibodies, Monoclonal, Humanized / Q000627:therapeutic use*; D001787:Blood Group Incompatibility / Q000188:drug therapy*; D002470:Cell Survival; D003167:Complement Activation / Q000187:drug effects; D003176:Complement C3 / Q000276:immunology; D015936:Complement C5a / Q000037:antagonists & inhibitors* / Q000276:immunology; D004912:Erythrocytes / Q000276:immunology; D005260:Female; D017261:Glycosylphosphatidylinositols / Q000097:blood; D006456:Hemoglobinuria / Q000209:etiology; D006457:Hemoglobinuria, Paroxysmal / Q000150:complications / Q000628:therapy; D006801:Humans; D019300:Medical Errors; D011239:Prednisolone / Q000627:therapeutic use; D065227:Transfusion Reaction / Q000097:blood / Q000188:drug therapy* / Q000652:urine
chemical_list: D000017:ABO Blood-Group System; D061067:Antibodies, Monoclonal, Humanized; C038245:C3 protein, human; D003176:Complement C3; D017261:Glycosylphosphatidylinositols; D015936:Complement C5a; D011239:Prednisolone; C481642:eculizumab