Hydroxyurea for Children with Sickle Cell Disease in sub-Saharan Africa: A Summary of the Evidence, Opportunities, and Challenges.

Abstract

Sickle cell disease (SCD) is a common and life-threatening inherited blood disorder that affects more than 300,000 newborns per year. Because of the origins of the sickle gene mutation as a protective mechanism against malaria for those with sickle cell trait, more than 90% of annual SCD births are in sub-Saharan Africa (sSA). Over the past several decades, there have been many important advances in the care of individuals with SCD, including early diagnosis through newborn screening programs (NBS), prophylactic penicillin, the development of vaccines to prevent invasive bacterial infections, and the emergence of hydroxyurea as the primary disease-modifying pharmacologic therapy. These relatively simple and inexpensive interventions have significantly reduced the morbidity and mortality of Sickle cell anemia (SCA) such that individuals with SCD can live longer and more complete lives. Unfortunately, although these interventions are relatively inexpensive and evidence-based, they are only readily available for affected individuals living in high-income settings, representing <5% of the global SCD population. In sSA, where >90% of the global SCD burden exists, SCD still results in early mortality with 50-90% of infants likely dying before reaching 5 years of age. Recently, there are an increasing number of efforts in many African countries to prioritize SCA with pilot NBS programs, improved diagnostics, and expanded SCD education for health care professionals and the general public. It is essential to include access to hydroxyurea as a core component of any SCD care program, but there are still many barriers that prevent the widespread global use of hydroxyurea. Here, we summarize what we know about SCD and hydroxyurea use in Africa and discuss a strategy to respond to what we consider to be a public health imperative to maximize access to and appropriate use of hydroxyurea for all individuals with SCD using innovative dosing and monitoring strategies.