Alpha2-plasmin-inhibitor deficiency (Miyasato disease).

A 25-year-old man, born in Okinawa, Japan, had a haemorrhagic diathesis characterised by prolonged bleeding and ecchymoses after minor trauma and spontaneous joint haemorrhage. The frequency and severity of these episodes were reduced by an antiplasminic drug. Routine coagulation studies revealed no abnormalities except for significantly sshortened euglobulin-lysis time and whole-blood clot lysis time. Activities of all known clotting and fibrinolytic factors were within normal ranges but no circulating alpha2-plasmin inhibitor was found in the plasma. alpha2-plasmin inhibitor is a potent and fast-acting protease inhibitor. Studies of family members indicated that this abnormality was inherited as an autosomal and recessive gene.