The case for and against initiating either hydroxyurea therapy, blood transfusion therapy or hematopoietic stem cell transplant in asymptomatic children with sickle cell disease.

INTRODUCTION: The perception of an asymptomatic sickle cell disease (SCD) state is a misnomer. Children without overt symptoms, likely have subclinical disease beginning in infancy with progression into adulthood. Predictive models of SCD severity are unable to predict a subgroup of asymptomatic children likely to develop severe SCD. The introduction of penicillin prophylaxis, conjugated pneumococcal and Haemophilus influenzae type B vaccines have dramatically decreased the rate of life-threatening infections, while use of hydroxyurea in children has decreased pain and acute chest syndrome events. Use of transcranial Doppler coupled with regular blood transfusion therapy has decreased the rate of overt strokes and premature death associated with strokes. Currently, therapy for asymptomatic children includes hydroxyurea, regular blood transfusion or allogeneic hematopoietic stem cell transplant (allo-HSCT). AREAS COVERED: The pros and cons of initiating hydroxyurea, regular blood transfusion or allo-HSCT in asymptomatic children with SCD. EXPERT OPINION: Emerging evidence from observational studies indicates that hydroxyurea prolongs survival in children and adults with sickle cell anemia. Regular blood transfusions reduce incidence of strokes, acute chest and pain episodes, but is associated with the burden of monthly visits and excessive iron stores. Although curative, the perceived risk:benefit ratio associated with allo-HSCT limits its use in asymptomatic children.