Circulating Immune Complexes in Patients with Haemophilia and von Willebrand’s Disease

Circulating Immune Complexes in Patients with Haemophilia and von Willebrand’s Disease T. Aguado A. Celada F. Ortega M. Magallon J. Martin-Villar P.H. Lambert Patients with haemophilia or von Willebrand’s disease received repeated infusions of large amounts of plasma or antihaemo-philic factor concentrates. Some of the haemophiliac patients developed a factor VIII inhibitor or antibodies against other antigens contained in the concentrates. Prior to transfusion, in 63 patients with haemophilia A, the presence of circulation immune complexes (CIC) was detected in 31 % of the cases, by the conglutinin-binding assay (Cg BA) which allows quantitation of C3b-bearing immune complexes. By this method, CIC were also detected in 4 of 6 patients with Fl, 6 of 11 patients with haemophilia B and 3 of 10 patients with von Willebrand’s disease. By the Clq binding assay (Clq BA) the presence of CIC was detected in 22% of patients with haemophilia A. Levels of CH50, C3, C4 and factor B were within normal limits. Abnormally high levels of C3d were found in 28% of patients with haemophilia A. The presence of CIC in these patients did not correlate with the age of the patient the number of transfusions or the presence of HBs Ag or HBs Ab in the serum. Levels of CIC were determined by the Cg BA before and 24 h after transfusion of cryoprecipitate in 20 patients with haemophilia A. The mean value before transfusion was 12.55 + 22.39 AHG μg eq/ml and 24 h after 27.55 + 35.15 AHG μg eq/ml (p 0.01). Serial studies in 5 patients showed that the levels of CIC remained constant 24.48 and 72 h after injection of cryoprecipitate. At present further studies are in progress to characterize the composition of these immune complexes and their relation with the administration of factor VIII.