Abnormal platelet function in Wilson's disease

A 15-year-old Arab girl was admitted because of weakness, amenorrhea and behavioral disturbance. She had an expressionless facies, slight jaundice and Kayser-Fleischer rings. Liver function was abnormal and ceruloplasmin and serum copper levels were low. The 24-hour urinary copper excretion was increased. Bleeding and clotting times were normal but there was decreased platelet aggregation in the presence of ADP (37%) and epinephrine (43%) (normal values 70%-100%). Platelet factor-3 activity was 75 sec (normal 35-45 sec). Platelet copper concentration was ten times greater than in the control. Wilson's disease was diagnosed in her two sisters who were asymptomatic but who also showed abnormality in platelet aggregation with ADP and epinephrine, and one of whom had low platelet factor-3 activity. Abnormalities in platelet function in Wilson's disease must be considered before surgical procedures or liver biopsy.