Treatment of chronic immune thrombocytopenic purpura with rituximab.

Objective. To evaluate the rituximab treatment in children with chronic immune thrombocytopenic purpura Methods. This study included ten children with chronic immune thrombocytopenic purpura, which were nonresponsive to Steroid (S), IVIG and anti-D treatments. Rituximab was given with a dosage of 375 mg/m2 weekly for 4-6 weeks. Initial platelet count was less than 30x109/L and responses were assessed in follow-up. The patients’ groups were categorized as complete remission (CR);a platelet count ≥150x109/L,partial remission (PR);a platelet count ranging from 50x109/L to 150x109/L, minimal remission (MR); a platelet count ranging from 30x109/L to 50x109/L and no response (NR); a platelet count less than 30x109/L. Results. Of our patients, four female and six male, their ages ranged from 39 mth to 13 yr and the mean age was 83.4±44.58 mo. None of the patients was splenectomized. The follow-up period after rituximab treatment ranged between 12 to 42 mo and the mean follow-up period was 25.10±13.03 months. While on this treatment, we had a CR in two patients, a PR in one, a MR in three, but no response in four. The patients in CR/PR are still being followed as in remission and they have 40 mo of mean follow-up period. The three patients in MR had a decrease in values of platelets earliest in one mo and the latest in four mo. Adverse effects of rituximab, such as itching and scraps that were not clinically significant were observed in three patients during rituximab infusion. There were no increase in infections after rituximab in any patient. Conclusion. CR was found in 20% of our patients, PR in 10% and MR in 30% with rituximab. On this treatment, while some series had good outcomes with this treatment (72%-100%, remission ratios), but many series, such as ours, had a poor response rate contrast to many reported case series in the literature. This condition may be associated with the age of our most patients who were young at the time of commenced rituximab. However, we believe that more studies are required to elucidate the reasons for different results in different case series reported in literature.