Review Question - QID 104658

A left-sided, middle cerebral artery cerebrovascular accident (CVA) in an African-American child is concerning for underlying sickle cell disease (SCD), which can be evaluated initially with a peripheral blood smear.

Sickle cell disease refers to a group of autosomal recessive genetic disorders characterized by the presence of sickled hemoglobin in red blood cells. Diagnosis can be made using peripheral blood smear to identify sickled red cells. Hemoglobin electrophoresis is generally also used to confirm the diagnosis by identifying and quantifying the amount of hemoglobin S (HbS) in a patient's blood.

Mehta et al. discuss the importance of screening children with known sickle cell anemia to reduce the incidence of stroke. Screening is conducted using transcranial Doppler ultrasonography to identify those with an abnormal transcranial blood-flow velocity (TBV). Children who screen positive (decreased TBV) are then recommended to begin chronic blood transfusions.

de Montalembert, in an article discussing the management of sickle cell, notes that the risk of stroke is considerably high in children and adults with sickle cell disease. The authors noted the prevalence of clinical evidence of stroke to be 11% by age 20 years. The annual incidence is 1.02% between ages 2 and 5 years.

Illustration A is a peripheral blood smear showing sickled red blood cells, diagnostic of sickle cell anemia.

Incorrect Answers:
Answer 1: Familial hyperlipidemia, revealed by serum lipid panel, can certainly cause CVA in a child. However, this is less common cause than sickle cell anemia and is very uncommon in African Americans.
Answer 3: Carotid stenosis, identified by carotid ultrasonography, is a cause of CVA in older adults with a long-standing history of atherosclerosis.
Answer 4: The PT and PTT are used to identify bleeding disorders and to monitor anticoagulation.
Answer 5: Antiphospholipid antibody syndrome can be the cause of a clotting disorder. The presentation is usually a woman of child-bearing age who has experienced one or more spontaneous abortions.