Pediatric Sickle Cell Disease: Despite the Successes, There Is Still Much More to Do
Sickle cell disease (SCD) affects a profound number of people worldwide, including approximately 100,000 people in the United States. One in 365 black infants have SCD, and one in 13 have sickle cell trait. The field of pediatric SCD care has grown significantly and achieved numerous clinical successes with reduction in morbidity and mortality throughout the past few decades, attributable to newborn screening programs, penicillin prophylaxis, and improved overall medical care despite lack of U.S. Food and Drug Administration–approved disease modifying therapy. More recently, hydroxyurea for patients as young as six months and standard-of-care transcranial Doppler screening, with primary prevention for those identified as high risk for stroke, have contributed to improved outcomes. Multiple large-scale trials (e.g., BABY HUG, SWiTCH, TWiTCH, STOP, etc.) have been completed in children with SCD, and current studies are focusing on utilizing these interventions in underserved worldwide populations.
These successes are remarkable given the relative lack of research studies in SCD across the U.S. and worldwide compared to other chronic diseases or malignancies. Hydroxyurea was not approved for pediatric SCD until late 2017; newer pharmacologic agents such as L-glutamine are now available or on the horizon, as is the case with selectin-targeted agents. These studies have duration or frequency of pain crisis as primary outcomes. Currently, there are increased efforts focused on potential curative strategies in pediatric SCD (i.e., bone marrow transplantation and gene therapy), spearheaded by the National Heart, Lung, and Blood Institute Cure Sickle Cell Initiative. ASH has also made SCD a research priority, potentially offering opportunities for trainees and young faculty to become engaged in exciting areas of research growth.1
There is still much to be done in pediatric and adolescent sickle cell care. Although mortality has dropped significantly in children with SCD throughout the past several decades, death accelerates with onset of adulthood. One study found that the mortality rate for young adults between 1999 and 2009 more than doubled compared to 15- to 19-year-olds, and that they struggle with increasing disease severity and complications.2,3 Comprehensive multidisciplinary care is critical, but these resources are often lacking in many areas across the United States and in under-resourced communities around the world. Cost of care is also a growing concern. As medical costs increase, especially with new therapeutic options, this places an increased burden on patients who may already face other economic challenges outside of their medical care.
ASH’s advocacy efforts are inspiring, and I hope further opportunities for trainee involvement at the research, clinical, and advocacy levels emerge in the future. There were several “Blood Drops on SCD” sessions at ASH-a-Palooza, and whether the focus is on basic or translational science, clinical trials, or optimization of care, we must ride this wave as the next generation of hematologists. Children and adolescents with SCD are growing up healthier, but as future hematologists, we hold the key to continued comprehensive improvements in this arena.
1American Society of Hematology. State of Sickle Cell Disease: 2016 Report. ASH. 2016.
2Hamideh D, Alvarez O. Sickle cell disease related mortality in the United States (1999-2009). Pediatr Blood Cancer. 2013;60:1482-1486.
3Kayle M, Docherty SL, Sloane R, et al. Transition to adult care in sickle cell disease: A longitudinal study of clinical characteristics and disease severity. Pediatr Blood Cancer. 2018;24:e27463.