title: Effects of hydroxyurea treatment for patients with hemoglobin SC disease.
abstract: Although hemoglobin SC (HbSC) disease is usually considered less severe than sickle cell anemia (SCA), which includes HbSS and HbS/β(0) -thalassemia genotypes, many patients with HbSC experience severe disease complications, including vaso-occlusive pain, acute chest syndrome, avascular necrosis, retinopathy, and poor quality of life. Fully 20 years after the clinical and laboratory efficacy of hydroxyurea was proven in adult SCA patients, the safety and utility of hydroxyurea treatment for HbSC patients remain unclear. Recent NHLBI evidence-based guidelines highlight this as a critical knowledge gap, noting HbSC accounts for ∼30% of sickle cell patients within the United States. To date, only 5 publications have reported short-term, incomplete, or conflicting laboratory and clinical outcomes of hydroxyurea treatment in a total of 71 adults and children with HbSC. We now report on a cohort of 133 adult and pediatric HbSC patients who received hydroxyurea, typically for recurrent vaso-occlusive pain. Hydroxyurea treatment was associated with a stable hemoglobin concentration; increased fetal hemoglobin (HbF) and mean corpuscular volume (MCV); and reduced white blood cell count (WBC), absolute neutrophil count (ANC), and absolute reticulocyte count (ARC). Reversible cytopenias occurred in 22% of patients, primarily neutropenia and thrombocytopenia. Painful events were reduced with hydroxyurea, more in patients >15 years old. These multicenter data support the safety and potentially salutary effects of hydroxyurea treatment for HbSC disease; however, a multicenter, placebo-controlled, Phase 3 clinical trial is needed to determine if hydroxyurea therapy has efficacy for patients with HbSC disease.
authors.affiliation: Division of Hematology, Children's National Medical Center, Washington, DC.|Division of Hematology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
authors.forename: Lori
authors.initials: L
authors.lastname: Luchtman-Jones
authors.affiliation: Coordinating Center for Clinical Trials, University of Texas School of Public Health, Houston, Texas.
authors.forename: Sara
authors.initials: S
authors.lastname: Pressel
authors.affiliation: Division of Pediatric Hematology/Oncology, University of Alabama, Birmingham, Alabama.
authors.forename: Lee
authors.initials: L
authors.lastname: Hilliard
authors.affiliation: Division of Pediatric Hematolgoy/Oncology, Emory University/Children's Healthcare of Atlanta, Atlanta, Georgia.
authors.forename: R Clark
authors.initials: RC
authors.lastname: Brown
authors.affiliation: Division of Pediatric Hematology/Oncology, University of Mississippi Medical Center, Jackson, Mississippi.
authors.forename: Mary G
authors.initials: MG
authors.lastname: Smith
authors.affiliation: Division of Hematology Oncology and Stem Cell Transplantation, Ann and Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois.
authors.forename: Alexis A
authors.initials: AA
authors.lastname: Thompson
authors.affiliation: Division of Pediatric Hematology Oncology and Stem Cell Transplantation, Columbia University Medical Center, New York, New York.
authors.forename: Margaret T
authors.initials: MT
authors.lastname: Lee
authors.affiliation: Division of Pediatric Hematology/Oncology, Duke University Medical Center, Durham, North Carolina.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Rothman
authors.affiliation: Division of Pediatric Hematology/Oncology, The University of Texas Southwestern Medical Center, Dallas, Texas.
authors.forename: Zora R
authors.initials: ZR
authors.lastname: Rogers
authors.affiliation: Cancer and Blood Disorders Program, Children's Hospital of the King's Daughters, Norfolk, Virginia.
authors.forename: William
authors.initials: W
authors.lastname: Owen
authors.affiliation: Division of Pediatric Hematology/Oncology, University of South Alabama, Mobile, Alabama.
authors.forename: Hamayun
authors.initials: H
authors.lastname: Imran
authors.affiliation: Division of Pediatric Hematology/Oncology, Rady Children's Hospital/University of California San Diego, San Diego, California.
authors.forename: Courtney
authors.initials: C
authors.lastname: Thornburg
authors.affiliation: Division of Pediatric Hematology & Oncology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.
authors.forename: Janet L
authors.initials: JL
authors.lastname: Kwiatkowski
authors.affiliation: Division of Hematology Oncology, Cohen Children's Medical Center, New Hyde Park, New York.
authors.forename: Banu
authors.initials: B
authors.lastname: Aygun
authors.affiliation: Hematology/Oncology Division, Children's Hospitals and Clinics of Minnesota, Minneapolis, Minnesota.
authors.forename: Stephen
authors.initials: S
authors.lastname: Nelson
authors.affiliation: Division of Pediatric Hematology & Oncology, University of South Carolina, South Carolina, Columbia.
authors.forename: Carla
authors.initials: C
authors.lastname: Roberts
authors.affiliation: Hematology/Oncology, Nemours Children's Clinic, Jacksonville, Florida.
authors.forename: Cynthia
authors.initials: C
authors.lastname: Gauger
authors.affiliation: Pediatric Sickle Cell Anemia Program, University Hospitals/Rainbow Babies and Children's Hospital, Cleveland, Ohio.
authors.forename: Connie
authors.initials: C
authors.lastname: Piccone
authors.affiliation: Division of Hematology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
authors.forename: Theodosia
authors.initials: T
authors.lastname: Kalfa
authors.affiliation: Division of Pediatric Hematology/Oncology, University of Miami, Miami, Florida.
authors.forename: Ofelia
authors.initials: O
authors.lastname: Alvarez
authors.affiliation: Division of Hematology, University of Colorado, Denver, Colorado.
authors.forename: Kathryn
authors.initials: K
authors.lastname: Hassell
authors.affiliation: Coordinating Center for Clinical Trials, University of Texas School of Public Health, Houston, Texas.
authors.forename: Barry R
authors.initials: BR
authors.lastname: Davis
authors.affiliation: Division of Hematology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
authors.forename: Russell E
authors.initials: RE
authors.lastname: Ware
mesh_terms: D000293:Adolescent; D000755:Anemia, Sickle Cell / Q000188:drug therapy* / Q000235:genetics; D000986:Antisickling Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D002648:Child; D005260:Female; D006801:Humans; D006918:Hydroxyurea / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D000986:Antisickling Agents; D006918:Hydroxyurea