Authors: Arshad, Jawad A.; Klausner, Howard A.; Lewandowski, Christopher (Henry Ford Hospital, Detroit, MI)
Abstract: Stroke in sickle cell disease (SCD) is the leading cause of cerebrovascular accident in children, and is the leading cause of death in sickle cell patients. SCD is caused by the substitution of a valine for a glutamate in the hemoglobin. This leads to rigidity of the hemoglobin and it precipitates readily during hypoxemia. SCD affects both small and large blood vessels. The sludging of the red blood cells causes reactive changes to blood vessels leading to intimal hyperplasia. The Cooperative Study of Sickle Cell Disease has reported four risk factors for stroke in sickle cell patients: i) previous transient ischemic attack, ii) low steady state hemoglobin, iii) frequent/recent acute chest syndrome, and iv) elevated systolic blood pressure. Other risk factors are genetic, environmental, and infectious. Stroke in sickle cell disease is usually “silent,” and so most cerebrovascular accidents are not clinically apparent. Young children with SCD are especially at risk for stroke, and require close neuropsychological testing to monitor their performance. Transcranial Doppler is a useful modality that compares well with MRI to assess for stroke. The mainstay of therapy is preventive. In acute presentations of stroke, the standard antiplatelet therapy including thrombolytics can be used. Hydroxyurea and a routine transfusion regimen is used for prevention of stroke in SCD.