Sickle cell disease: A 75-year journey

Abstract

Sickle cell disease (SCD) is a disorder characterized by the polymerization of hemoglobin chains in the deoxy-form, sickling of red blood cells, and hence vaso-occlusive crisis, multiple organ damage, and increased mortality due to an inherited defect in hemoglobin structure. SCD can also lead to a host of complications, which include acute chest syndrome, avascular necrosis, stroke, pulmonary hypertension, splenic sequestration, gallstones, deep vein thrombosis, pregnancy complications, and end-organ damage. Complications are of varying complexities and can be as grave as life-threatening. According to a report in 2005, the median life expectancy for male and female patients with SCD in the United States (US) was around 42 and 38 years, respectively. However, the survival rate of SCD patients in high-income countries has steadily improved. Treatment options that were mainly for symptomatic relief and led to better well-being of the patient, containment of complication recurrence, and decrease in mortality rates have evolved into curative treatment options such as stem cell transplantations and gene therapy. The present paper is a review of the disease, its complications and implications on the community, and a historical tracking of the evolution of treatment options up to modern-day gene therapy.

Keywords

Sickle cell disease / Treatments / Myeloablative transplantation / Gene therapy / Casgevy / Lentiviral

Funding

None.

Conflict of interest

The authors declare they have no competing interests.

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