Combined deficiency of coagulation factors II, VII, IX, and X: a case of probable congenital origin.

Combined deficiency of coagulant activity of the vitamin K-dependent factors was found in a 14-year-old boy suffering from severe hemorrhages. Immunoassays revealed the presence of acarboxyprothrombin. The bleedings could be controlled, but the coagulation defects persisted during more than 2 years' follow-up and could not be corrected by oral or parenteral vitamin K. No intoxication or underlying disease was found. The abnormality was considered a congenital disorder of the carboxylation of prothrombin.