FAMILIAL THROMBOPHILIA ASSOCIATED WITH HIGH-LEVELS OF PLASMINOGEN-ACTIVATOR INHIBITOR

A family with defective fibrinolytic abnormalities and recurrent thrombotic events is described. Impaired fibrinolysis was associated with high activity and concentration of fast-acting plasminogen activators inhibitor (PAI-1). Acquired conditions associated with PAI-1 increase were excluded. After venous occlusion testing, a different behaviour of fibrinolytic activity inhibition was seen in the family members. In the propositus and in two relatives only tissue (t-PA) plasminogen activity inhibition was found; in two other members, both t-PA and urokinase-type plasminogen activities were completely inhibited by the high PAI-1 levels. This fibrinolytic defect seems to be familial and transmitted as an autosomal trait.