Lower Dosages of Intravenous Immunoglobulin (IVIg) in Treating Immune Thrombocytopenia with Long-Term Follow-up of Three Years

This study compared the effects of different dosages of intravenous immunoglobulin (IVIg) against immune thrombocytopenia. A total of 167 patients, 91 adults and 76 children, with ITP, followed-up for 3 years in the case-control study, were each divided into three subgroups according to the dosages of IVIg administered: group A (0.2g/kg/day), group B (0.3g/kg/day), group C (0.4g/kg/day). The therapeutic response in 91 adult patients did not differ significantly among the three groups of IVIg dosages (P=0.459). The response rate of IVIg treatment in the three adult groups was 97.1% for group A, and 97.2% for group B, 100% for group C. The mean time for raising platelets to 30 ×10⁹/L in group A was 2.5 days, group B 3.2 days, group C 2.9 days (P=0.324). The median IVIg consumption in group A was 0.83 g/kg, group B 1.22 g/kg, and group C 1.64 g/kg (P<0.01). Similar results were shown in the children groups. The follow-up results showed no significant difference of clinical outcome between groups A, B and C. In conclusion, low-dose IVIg treatment is shown to be as effective as high-dose regimen without increasing the risk of developing the patients into chronic ITP conditions, suggesting that ITP patients could be treated more cost-effectively by lower than conventional dosage of IVIg regimen.