Familial thrombosis due to antithrombin III deficiency in a Greek family.

A Greek family with hereditary antithrombin III (AT III) deficiency associated with venous thrombosis is reported. 5 members of the family were affected. In these patients, AT III and heparin cofactor activities were decreased. Immunoreactive AT III showed a positive correlation to both AT III and heparin cofactor activities. alpha2-Macroglobulin and alpha1-antitrypsin were normal. The pattern of inheritance of the defect is autosomal dominant.