3-YEAR FOLLOW-UP OF HYDROXYUREA TREATMENT IN SEVERELY ILL CHILDREN WITH SICKLE-CELL DISEASE

Purpose: To observe the safety and efficacy of hydroxyurea (HU), a dru g that stimulates fetal hemoglobin (Hb F) production, in previously se verely ill children with sickle cell disease. Patients and Methods: HU was given in an uncontrolled study to 35 children with sickle cell di sease, aged from 3 to 20 years, suffering from frequent painful crises . Mean duration of treatment was 32 months (range: 12-59 months). Resu lts: HU induced an increase in Hb F levels in all children but one; th is increase was maximal after 9 months of treatment, was largely susta ined thereafter, and was related to HU dose and inversely to patients' age. We also noted an apparent reduction in crisis, which occurred pr incipally after 3 months of therapy and did not seem strictly correlat ed with the rise in Hb F level. No serious hematopoietic complication was observed. Growth curves and sexual development were not modified. Conclusion: Our data support the efficacy of HU in reducing painful ev ents in children with sickle cell disease. Short- and middle-term tole rances are good. Thus, we think that HU can be given to children affec ted by frequent and severe painful crises. We recommend, however, very cautious use of this drug, because its long-term effects in children are still unknown.