Congenital Deficiency of α2-Plasmin Inhibitor in Three Sisters

Abstract

3 young Japanese sisters with congenital α₂-plasmin inhibitor (α₂-PI) deficiency are reported. They have mild umbilical bleeding and/or repeated prolonged bleeding after minor trauma, but rarely spontaneous bleedings. The most characteristic hemostatic findings were shortened whole blood clot lysis time and euglobulin lysis time. Activities of all hemostatic factors except α₂-PI were within normal range. Both functional and immunological absence of α₂-PI were found in the plasma, and this failure to detect α₂-PI was not corrected by the addition of the patient’s plasma of the first described case of α₂-PI deficiency. Clinical and laboratory data revealed that these patients were probably homozygous for α₂-PI deficiency and born of heterozygous parents, but not of consanguineous ones. Bleeding episodes due to deficiency of (α₂-PI in these patients were well controlled by an antifibrinolytic agent, tranexamic acid.