Hydroxyurea for the treatment of sickle cell disease

In this study 21 adults with severe form of sickle cell disease (SCD; sickle cell anaemia, n = 15; Hb S/beta degree-thal, n = 6) were treated with hydroxyurea (HU) to assess the effectiveness of the drug in managing SCD. The individual dose was selected for each patient. The dose selection was based on the HU clearance study. Thereafter, the patients received daily doses of 15-20 mg/kg body weight. An evaluation data form was filled out at the monthly visit. The severity index (SI) of the disease was determined and haematological parameters including red cell indices, platelet counts, reticulocyte counts, irreversibly sickled cells, red cell deformability, Hb F, Hb F cells, total and direct bilirubin levels were measured prior to treatment, at follow-up intervals during treatment and after cessation of treatment. The trial period lasted 3 months. Statistically significant improvement was observed in the clinical presentation, haematological and biochemical parameters. Hb F level and F cells showed a significant increase in most patients, but to a variable degree. A major resultant effect was an increase in mean cell volume. Our experience shows that HU can be used for the treatment of severe forms of SCD with no major side effects, provided that the doses are monitored and that laboratory investigations are regularly undertaken.