Value of hydroxyurea therapy in children severely affected with sickle cell disease.

Background. - Sickling of red cells in patients with sickle cell anemia causes painful vaso-occlusive crises (VOC). Hydroxyurea (HU) has been shown to increase HbF production and therefore has the potential to prevent these crises in adult patients. This work aimed to confirm its clinical efficiency in children. Patients and methods. - Since 1993, eight children and adolescents (5-16) years old) with hemoglobinopathy (HbS > 65%) were given HU (14 to 27 ng/kg/day) for a mean duration of 10 months. We did a retrospective study about different data, especially inpatient days for VOC, pain intensity during these crises, individual transfusion requirements and HbF level. Results. - As the HbF levels increased we observed a reduction of the inpatient days for VOC, of the pain intensity during these crises and of the mean number of units transfused per month. Conclusion. - HU is the first clinically acceptable drug shown to prevent painful crises in adults but also in children with sickle cell anemia. However, its effects and potential toxicity are still unknown and the other therapeutic possibilities have to be considered before starting a long-term treatment with HU.