Congenital thrombotic disorders.

The investigation of kindreds with recurrent thrombotic disease has advanced the understanding of the mechanisms of coagulation and fibrinolysis. In those cases where an etiology has been established, congenital thrombotic disorders are associated either with deficiencies or qualitative abnormalities in inhibitors of activated coagulation factors, qualitative abnormalities of fibrinogen, fibrinolytic defects that impair clot lysis, or an inborn error of metabolism, homocystinuria. The etiologies of congenital thrombotic disorders, their clinical features, and an approach to their laboratory diagnosis are summarized in this review.