ISSN 2997-1036
International Journal of Hematology | Vol. 7, No. 2, February 2016 | pp. 9–16
DOI: 10.46882/2016/IJH/000074
Original Article
Title: Impact of hydroxyurea optimization on transcranial Doppler velocity variations in children with sickle cell anemia
Names of Authors: S. T. Adeyemi¹, U. V. Okoye², W. X. Salami³
Authors’ Affiliations: ¹Department of Haematology and Blood Transfusion, Obafemi Awolowo University, Ile-Ife, Nigeria; ²Department of Medicine, University of Nigeria Teaching Hospital, Enugu, Nigeria; ³Department of Paediatrics, Ahmadu Bello University, Zaria, Nigeria
Abstract: Elevated time-averaged maximum mean velocities on transcranial Doppler (TCD) ultrasonography identify children with sickle cell anemia who carry an exceptionally high risk of primary stroke. This prospective cohort study evaluated the efficacy of optimized hydroxyurea therapy for reducing elevated transcranial Doppler velocities in 54 pediatric patients (aged 2 to 12 years) presenting with conditional (170 to 199 cm/s) or abnormal (≥ 200 cm/s) baseline velocities. Hydroxyurea was initiated at 15 mg/kg/day and titrated to the maximum tolerated dose over 12 months. Repeat transcranial Doppler evaluations were performed at 6 and 12 months. The mean baseline velocity fell significantly from 186.4 ± 12.5 cm/s to 154.2 ± 10.4 cm/s at month 12 (P < 0.001). Concurrently, fetal hemoglobin concentrations rose from a baseline mean of 6.2 ± 1.8% to 16.5 ± 3.2%. None of the children in the conditional or abnormal cohorts progressed to a primary stroke during the study window. Optimizing hydroxyurea to maximum tolerated doses effectively reduces high cerebrovascular blood flow velocities, providing an accessible and non-invasive pharmacological pathway for primary stroke prevention in pediatric sickle cell populations.
Keywords: Sickle cell anemia, hydroxyurea, transcranial Doppler, fetal hemoglobin, pediatric stroke
Manuscript Timeline: Received: November 05, 2015; Revised: December 14, 2015; Accepted: January 08, 2016; Published: February 18, 2016