title: Acute haemolytic transfusion reactions due to weak antibodies that in vitro did not seem to be clinically significant.
abstract: OBJECTIVE
  In the present article, we report on two patients with acute haemolytic transfusion reactions (AHTRs), and whom we were unable to transfuse, owing to alloantibodies that in vitro did not seem to be clinically significant.
  
  
  METHODS
  The patients were a 67-year-old male and a 64-year-old female, both of whom developed antibodies to red blood cells (RBCs) after repeat blood transfusions. Serological analyses were carried out using standard techniques.
  
  
  RESULTS
  Both patients developed an AHTR of the intravascular type following blood transfusions. Serological re-examination revealed weakly reactive alloantibodies with anti-JMH specificity in one patient, and with unclear specificity in the second. Rechallenging the patients with 15-30 ml of packed RBCs caused AHTRs, and blood transfusion became impossible in both cases.
  
  
  CONCLUSIONS
  Weak alloantibodies that in vitro do not seem to be clinically significant may cause severe AHTRs.
authors.affiliation: Institute of Transfusion Medicine, Charité Campus Virchow-Klinikum, Humboldt-Universität Berlin, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Hoppe
authors.forename: L
authors.initials: L
authors.lastname: Pastucha
authors.forename: A
authors.initials: A
authors.lastname: Seltsam
authors.forename: A
authors.initials: A
authors.lastname: Greinacher
authors.forename: A
authors.initials: A
authors.lastname: Salama
mesh_terms: D000208:Acute Disease; D000368:Aged; D000917:Antibody Formation; D018929:Cell Culture Techniques; D017707:Erythrocyte Transfusion / Q000009:adverse effects*; D005260:Female; D006461:Hemolysis; D006801:Humans; D007518:Isoantibodies / Q000276:immunology*; D008297:Male; D008875:Middle Aged
chemical_list: D007518:Isoantibodies