[A Japanese family with congenital abnormal plasminogen].

A Japanese family with congenital abnormal plasminogen is reported. The patient was a 44-year-old male with no past history of thrombosis. Since only the plasminogen (PLG) activity was reduced on laboratory tests before surgery for lumbar disc herniation, coagulation and fibrinolysis studies were performed in the patient and his family. The patient underwent resection of the nucleus pulposus and posteriorlateral fixation of the lumbar spine. The PLG activity was 8% in the patient and his sister, 55% in his father, and 53% and 48% in his nephew brothers. The PLG antigen level was normal in all members of his family examined. IEF of PLG antigen showed abnormal patterns in which all bands were shifted slightly to the cathode side in the patient and his sister, but his father and nephew brothers exhibited duplicated bands showing combinations of normal and abnormal patterns. From these results, the proband and his sister were considered to be homozygotes, and his father and nephew brothers to be heterozygotes for congenital abnormal plasminogen. Acute reactant substances (fibrinogen, CRP, CPK, C1IN, alpha 1AT, etc.) and PIC (plasmin, alpha 2-plasmin inhibitor complex) increased after the operation due to the surgical insult, but the surgery did not trigger thrombosis. This patient is considered not to have developed thrombosis although he was a homozygote for congenital abnormal plasminogen, because the anticoagulation process until thrombogenesis was normal.