Familial Association of Hypoplasminogenemia and Heterozygous Factor V Deficiency

Abstract

The coinheritance of hypoplasminogenemia and heterozygous factor V deficiency in a relative with thrombotic disease and no hemorrhagic tendency is described. The proposita, a 28-year-old woman, suffered from neurologic dis turbances due to two ischemic cerebral lesions confirmed by nuclear magnetic resonance scan. She was found to be affected with heterozygous plasminogen deficiency in a coagulation study for inherited thrombophilia. Moreover, she disclosed a prolongation of prothrombin time and activated partial throm boplastin time, which was compatible with heterozygous factor V deficiency. Her father, with a history of deep vein thrombo sis, was also affected with plasminogen deficiency, as well as three brothers and one sister who were asymptomatic. The mother of the proposita showed borderline or slightly decreased factor V levels and normal plasminogen levels; she was there fore considered to be heterozygous for factor V deficiency. Heterozygous factor V deficiency was also found in one brother and one sister of the proposita, and they were both asymptomatic. Among the other available family members, one brother and one sister of the proposita, all asymptomatic for either thrombotic or bleeding events, showed a normal clotting and fibrinolytic profile. To our knowledge, this is the first case of combined heterozygous plasminogen and factor V defi ciency in the same family. Two of six patients with hypoplas minogenemia showed thrombotic events, and in one of these symptomatic cases the coexistence of factor V deficiency did not prevent the occurrence of thrombosis. As expected, no hemorrhagic tendency was observed in patients with heterozy gous factor V deficiency, who may be mildly symptomatic only in 10% of cases.