title: Clinical and laboratory effects of hydroxyurea in children and adolescents with sickle cell anemia: a Portuguese hospital study.
abstract: Our aim was to assess the efficacy and safety of hydroxyurea (HU) in children with severe forms of sickle cell anemia followed in a Portuguese hospital. We carried out an open-label uncontrolled prospective study, which included children with severe forms of sickle cell anemia. Hydroxyurea was started at 15 mg/kg/day and increased to a maximum dose of 25 mg/kg/day. Patients were monitored to assess compliance, clinical and hematological response and toxicity. Nine children and adolescents, five girls and four boys, with a median age of 13 years (range 8 to 16) were enrolled in the study during a period of 24 months. All patients completed at least 15 months of therapy. Hb F was significantly increased, from a mean of 7.0 +/- 3.9% to 13.7 +/- 5.3% (p = 0.028). Clinically, all patients responded significantly with a reduction of 80% in the number of vaso-occlusive crises (VOC), 69% in hospital admissions, 76% in hospitalization days and 67% in transfusion requirements, without significant toxicity. We concluded that, in our population, HU proved to be effective in increasing Hb F levels, and in decreasing hospitalizations for VOC and transfusion requirements with no major side effects. Long-term clinical follow-up is important to certify benefit maintenance.
authors.affiliation: Pediatric Immune-Hematology Unit, Dona Estefânia's Pediatric Hospital, Lisbon, Portugal. ligiabbraga@netcabo.pt
authors.forename: Lígia Barbosa
authors.initials: LB
authors.lastname: Braga
authors.forename: Ana Cristina
authors.initials: AC
authors.lastname: Ferreira
authors.forename: Margarida
authors.initials: M
authors.lastname: Guimarães
authors.forename: Carlos
authors.initials: C
authors.lastname: Nazário
authors.forename: Paula
authors.initials: P
authors.lastname: Pacheco
authors.forename: Armandina
authors.initials: A
authors.lastname: Miranda
authors.forename: Isabel
authors.initials: I
authors.lastname: Picanço
authors.forename: Teresa
authors.initials: T
authors.lastname: Seixas
authors.forename: Lino
authors.initials: L
authors.lastname: Rosado
authors.forename: João M Videira
authors.initials: JM
authors.lastname: Amaral
mesh_terms: D000293:Adolescent; D000755:Anemia, Sickle Cell / Q000097:blood / Q000628:therapy*; D000986:Antisickling Agents / Q000008:administration & dosage*; D001803:Blood Transfusion; D002648:Child; D005260:Female; D005319:Fetal Hemoglobin / Q000032:analysis; D006761:Hospitals; D006801:Humans; D006918:Hydroxyurea / Q000008:administration & dosage*; D007755:Laboratories, Hospital; D008297:Male; D011174:Portugal; D011446:Prospective Studies
chemical_list: D000986:Antisickling Agents; D005319:Fetal Hemoglobin; D006918:Hydroxyurea