Stroke in a cohort of patients with homozygous sickle cell disease.

Strokes occurred in 17 of 310 children with homozygous sickle cell disease who were followed from birth, representing an incidence of 7.8% by the age of 14 years. Two children had subarachnoid hemorrhage, one having resolution of symptoms after aneurysm surgery and another dying of a presumed second hemorrhage 14 days later. The remaining 15 strokes were presumed to be cerebral infarction, although autopsy, angiographic, or computed tomographic evidence was available in only 8 children. There were 6 deaths, 2 in the acute event and 4 after recurrence, which occurred in 6 (46%) of 13 patients who survived the initial episode. There were 10 recurrent episodes at a median interval of 9 months after the initial event. Steady-state hematologic data revealed significantly higher leukocyte counts than in control subjects without strokes at age 1 year and in the last study preceding the stroke. The initial stroke coincided with an acutely lowered hemoglobin value in 5 patients (3 aplastic crises, 1 acute splenic sequestration, 1 probable pulmonary sequestration) and with painful crises in another 7 patients. We conclude that a high leukocyte count and an acute decrease of hemoglobin are risk factors for stroke in patients with homozygous sickle cell disease.