Benefits of delayed fetal hemoglobin (HbF) switching in sickle cell disease (SCD): a case report and review of the literature.

Sickle cell disease is an autosomal recessive hemoglobinopathy with significant morbidity and mortality. Complications include: vasoocclusive pain crisis, bacterial infection, cerebral vascular accident, acute chest syndrome, and chronic lung and kidney disease. Among many other factors affecting the severity of sickle cell disease, synthesis of fetal hemoglobin (HbF) emerged as an important prognostic factor and has long been recognized to decrease disease severity. This report discusses the attenuated clinical course of a child who continued to produce HbF well beyond the reported age of fetal switching. We further discuss the underlying genetic aspects of HbF production and review the pertinent literature.