Blood
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Stroke is a relatively frequent and severe complication of sickle cell disease. We performed cerebral arteriograms in 30 patients with sickle cell disease to evaluate the cause of acute neurologic deficits and to assess the effects of transfusion therapy given for a year or more after the acute episode. Twenty-three patients with motor and speech deficits had multiple abnormalities of major cerebral arteries. ⋯ The patients tolerated prolonged transfusion therapy well, despite progressive iron accumulation. Seven patients with smooth abnormalities of a single artery, nonocclusive changes, or with normal arteriograms did not receive transfusions. Only one of this group had recurrence of symptoms.
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Previous studies performed in vitro have indicated that platelets from patients with platelet-type von Willebrand's disease (vWD) have receptors for von Willebrand factor (vWF) already exposed on their surfaces and that the addition of purified vWF or cryoprecipitate to patient platelet-rich plasma under stirring conditions is capable of inducing platelet aggregation and secretion. The present work reports the results of the transfusion of cryoprecipitate in a patient with platelet-type vWD. ⋯ Shortening of the bleeding time occurs only very transiently. The results of this study provide direct evidence that, in patients with platelet-type vWD, an abnormal interaction of their platelets with plasma vWF occurs in vivo, resulting in the absence of high molecular weight vWF multimers, low platelet counts, and impaired hemostasis that are characteristic of this disease.