Arch Dis Child 98:908-914 doi:10.1136/archdischild-2012-302387
  • Review

Evidence review of hydroxyurea for the prevention of sickle cell complications in low-income countries

Open Access
  1. Mike English2,5
  1. 1School of Pharmacy, University of Nairobi, Nairobi, Kenya
  2. 2SIRCLE Collaboration, KEMRI-Wellcome Trust Research Programme, Nairobi, Kenya
  3. 3KEMRI-Wellcome Trust Research Programme
  4. 4Hematology and Blood Transfusion Unit, School of Medicine, University of Nairobi, Nairobi, Kenya
  5. 5Nuffield Department of Medicine, University of Oxford, Oxford, UK
  1. Correspondence to Dr Mercy Mulaku, KEMRI-Wellcome Trust Research Programme, P.O. Box 43640, Nairobi 00100, Kenya; mmulaku{at}
  • Received 23 May 2012
  • Revised 2 April 2013
  • Accepted 8 August 2013
  • Published Online First 30 August 2013


Hydroxyurea is widely used in high-income countries for the management of sickle cell disease (SCD) in children. In Kenyan clinical guidelines, hydroxyurea is only recommended for adults with SCD. Yet many deaths from SCD occur in early childhood, deaths that might be prevented by an effective, disease modifying intervention. The aim of this review was to summarise the available evidence on the efficacy, effectiveness and safety of hydroxyurea in the management of SCD in children below 5 years of age to support guideline development in Kenya. We undertook a systematic review and used the Grading of Recommendations Assessment, Development and Evaluation system to appraise the quality of identified evidence. Overall, available evidence from 1 systematic review (n=26 studies), 2 randomised controlled trials (n=354 children), 14 observational studies and 2 National Institute of Health reports suggest that hydroxyurea may be associated with improved fetal haemoglobin levels, reduced rates of hospitalisation, reduced episodes of acute chest syndrome and decreased frequency of pain events in children with SCD. However, it is associated with adverse events (eg, neutropenia) when high to maximum tolerated doses are used. Evidence is lacking on whether hydroxyurea improves survival if given to young children. Majority of the included studies were of low quality and mainly from high-income countries. Overall, available limited evidence suggests that hydroxyurea may improve morbidity and haematological outcomes in SCD in children aged below 5 years and appears safe in settings able to provide consistent haematological monitoring.

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