Hemolysis related to intravenous immunoglobulins is dependent on the presence of anti‐blood group A and B antibodies and individual susceptibility

• DOI: 10.1111/trf.14289
• Publication Date: 2017-08-25T11:46:40Z
• Authors: Orell Mielke; Stefano Fontana; Vesselina Goranov...; Amgad Shebl; Martin O. Spycher; Sandra Wymann; Billie L. Durn; John P. Lawo; Alphonse Hubsch; Abdulgabar Salama
• Keywords: Adult; Purpura, Thrombocytopenic, Idiopathic; Adolescent; Immunoglobulins, Intravenous; Middle Aged; Hemolysis; Antibodies; 3. Good health; ABO Blood-Group System; Young Adult; 03 medical and health sciences; 0302 clinical medicine; Antibody Specificity; Humans; Disease Susceptibility; Aged

BACKGROUNDPatients treated with intravenous immunoglobulins (IVIG) rarely experience symptomatic hemolysis. Although anti‐A and anti‐B isoagglutinins from the product are involved in most cases, the actual mechanisms triggering hemolysis are unclear.STUDY DESIGN AND METHODSA prospective, open‐label, multicenter, single‐arm clinical trial in 57 patients with immune thrombocytopenia treated with IVIG (Privigen, CSL Behring) was conducted.RESULTSTwenty‐one patients received one infusion (1 g/kg) and 36 received two infusions (2 × 1 g/kg) of IVIG. After a study duration of more than 2 years, no cases of clinically significant hemolysis as defined in the protocol were identified. Data of patients with mild hematologic and biochemical changes were analyzed in more detail. Twelve cases (10/23 patients with blood group A1 and 2/11 patients with blood group B, all having received 2 g/kg IVIG) were adjudicated as mild hemolysis (median hemoglobin [Hb] decrease, −3.0 g/dL); Hb decreases were transient, with partial or full recovery achieved by last visit. Eighteen patients (31.6%), all with non‐O blood group, of whom 16 (88.9%) received 2 g/kg IVIG, fulfilled post hoc criteria for hemolytic laboratory reactions. Red blood cell (RBC) eluates of all direct antiglobulin test–positive samples were negative for non‐ABO blood group antibodies. Blood groups A and B antigen density on RBCs appeared to be a risk factor for hemolytic laboratory reactions. Platelet response to treatment was observed in 42 patients (74%); eight of 12 patients with complete response had blood group A1.CONCLUSIONIsoagglutinins are involved in clinically nonsignificant hemolysis after treatment with IVIG, but individual susceptibility varies greatly.