Abstract

Sickle cell disease is an autosomal recessive hemoglobinopathy found mainly in populations of African and Mediterranean descent, including approximately 100,000 Americans. It is also very common in Spanish-speaking regions of Central America, South America, and parts of the Caribbean, in Saudi Arabia, and in India and Sri Lanka. The disorder is characterized most commonly by lifelong recurrent unpredictable vaso-occlusive pain that may be disabling, and by chronic tissue damage and organ dysfunction. There are several genotypes of the disease. Although SCD pain frequency generally varies between genotypes, it also varies between subjects even within genotype. It may worsen from childhood to adulthood. It may vary by gender. Its location, timing, and severity may be unpredictable.Until recently, pain in SCD had been characterized as episodes that were acute, periodic, and relatively rare. Crises were viewed as usually associated with hospitalization. Many patients utilized hospital or emergency care for pain once per year or less, so painful episodes in SCD were called vaso-occlusive “crises.”