Many authors have recounted the history of sickle cell disease in Africa and its first recognition in the United States Sickle-shaped red cells were first described in 1910 in the blood of a sick, anemic student from Grenada. Sickle hemoglobin (HbS) was identified in 1949 and the mechanism of inheritance of sickle cell anemia was established afterward. A single amino acid difference was found to distinguish the sickle β-globin chain from the normal one. The breadth of clinical and laboratory manifestations of sickle cell disease and its multitudinous complications still challenge the pediatrician, internist, general surgeon, obstetrician, orthopedist, ophthalmologist, psychiatrist, and subspecialists in each of these disciplines.
The features of sickle cell anemia change as life advances. Life's first decade, with declining fetal hemoglobin (HbF) levels, is typified by a risk of severe life-threatening infection, dactylitis, acute chest syndrome, splenic sequestration, and stroke; pain is often the torment of adolescence. If the worst of childhood and adolescent problems are survived or escaped, young adulthood can be a time of relative clinical quiescence, but sickle vasculopathy is likely to progress despite producing few symptoms. Chronic organ damage leading to pulmonary hypertension, deteriorating pulmonary function, renal failure, and late affects of previous cerebrovascular disease, including neurocognitive impairment, become paramount as years advance. Sickle cell anemia is noted for its clinical heterogeneity (Chapter 27). Any patient can have nearly all known disease complications; some have almost none, but die with a sudden acute problem.