Hydroxyurea therapy in 49 patients with major beta-thalassemia.

Major thalassemia is one of the most common hemoglobinopathies in many Asian countries including Iran. Pharmacologic agents such as hydroxyurea have been known to enhance the production of fetal hemoglobin, and also an increase in total hemoglobin level has been repeatedly reported during hydroxyurea treatment in patients with sickle cell disease and in several patients with intermediate beta-thalassemia. We evaluated the long-term efficacy and safety of hydroxyurea in major beta-thalassemic patients. Forty-nine beta-thalassemic patients enrolled in the study. The mean follow-up time was 60 months. The mean dose of hydroxyurea was 10 mg/kg per day (8-15 mg/kg). Before starting hydroxyurea, all patients underwent routine biochemical laboratory tests. Patients with low platelet count (<100,000/mm3), neutropenia (polymorphonuclear neutrophil<1,200/mm3), pregnancy, and on interferon treatment were excluded.Twenty-eight out of 49 enrolled patients were females with the mean age of 18.38 years (10-40 years). The mean packed red cell transfusions during one year before starting of hydroxyurea was 22.75 units which decreased to 6.02 units after treatment (P<0.01). The mean ferritin level during the first period was 2751.44 ng/mL, but decreased to 1594.20 ng/mL after one year of hydroxyurea therapy (P<0.001).We observed a substantial and persistent increase in hemoglobin level and a significant decrease in blood transfusion. Hydroxyurea treatment was well-tolerated and it did not cause any hematopoietic suppression except in one patient who developed transient thrombocytopenia which resolved after short period of hydroxyurea cessation. We did not encounter any malignancies including leukemia in the five-year follow-up.