New aspects on the efficacy of high-dose intravenous immunoglobulins in patients with autoimmune thrombocytopenia

Background and ObjectivesThe clinical significance of autoimmune thrombocytopenia (ITP) is reflected by bleeding and/or an increased bleeding risk due to low platelet counts. In most cases, treatment with high-dose (1-2 g/kg body weight) intravenous immunoglobulin has been demonstrated to result in an increase in platelet counts after one day of treatment. Until now, there is little information on the true beginning of therapy effect in patients treated with high-dose intravenous immunoglobulin. In this study, we focused on the kinetic of platelet counts and cessation of bleeding within the first 24 h of treatment. Materials and methodsNineteen patients with chronic ITP were treated with high-dose intravenous immunoglobulin due to clinically relevant bleeding and/or for increased bleeding risk. ResultsAlthough the response was variable in treated patients, cessation of bleeding was observed within 12 h in all such affected patients (n = 7), even in patients with platelet counts that were not increased (n = 3). Furthermore, platelet counts were observed to increase already within 1 h in 10 (53%) patients and within 8 h in 12 (63%) patients. ConclusionsFrom a clinical perspective, the onset of therapeutic effects of intravenous immunoglobulin in patients with ITP may occur at an earlier stage and be superior to that previously expected. Failure to measure an increase in platelets in the circulation of non-responders' may be explained by an increased consumption of platelets due to recognizable or unrecognizable bleeding in such affected patients.