Often the connecting bony parts of the joint are painful. Range of motion is often restricted because of the pain. Two-thirds of all strokes in people with sickle cell disease occur in children with an average age of 8 years. As the population ages, the incidence of these events also increases. Repeat strokes occur in two-thirds of all survivors within 3 years of the first stroke.
Blood clots affect the large vessels in the brain.
Bleeding may occur in the small vessels damaged by sickle cell disease. Retinal detachment is frequent. Hyphemas , bleeding in the eye, occur at the same rate as the general population, but complications are more common because of the increased sickling effect that the aqueous fluid in the eye promotes. Severe episodes are a frequent cause of impotency. People with sickle cell disease have weakened immune systems and are at increased risk for developing infection, especially in the lungs, kidneys, bones, and central nervous system.