any of several blood disorders characterized by dysfunctional platelets (platelet) (thrombocytes), which result in prolonged bleeding time, defective clot formation, and a tendency to hemorrhage. Inherited thrombocytopathies include von Willebrand disease; thrombasthenia, characterized by abnormal clot retraction and defective platelet aggregation; and Bernard-Soulier syndrome, characterized by unusually large platelets. In addition, thrombocytopathy is sometimes seen in cases of Down syndrome and Wiskott-Aldrich syndrome (an immune disorder).

Acquired thrombocytopathy has been known to be associated with such disorders as cirrhosis, leukemia, pernicious anemia, scurvy, and uremia. Temporary platelet dysfunction is sometimes induced by such drugs as antihistamines (antihistamine), aspirin, indomethacin, phenothiazines (phenothiazine), phenylbutazone, and tricyclic antidepressants (antidepressant).

Treatment for congenital thrombocytopathy is platelet transfusion (blood transfusion) to control bleeding. For acquired thrombocytopathies, cure of the underlying disease usually results in improved platelet function.