Coagulopathy in amyloidosis: combined deficiency of factors IX and X.
Combined severe deficiencies of blood clotting factors IX and X were observed in 2 patients who suffered from systemic amyloidosis. This unique deficiency state was marked by refractoriness to Vitamin K as well as to transfusion therapy. Increased antithrombin activity was present in both individuals and corresponded in time to the emergence of a monoclonal IgG kappa light chain paraprotein in 1. Both patients demonstrated profound bleeding disorders. It is hypothesized that the Vitamin K dependent factors have special affinity for amyloid deposits due to an unusual amino acid (gamma-carboxyglutamic acid) present in these factors.
D000328:Adult; D000686:Amyloidosis / Q000150:complications* / Q000473:pathology; D001778:Blood Coagulation Disorders / Q000150:complications*; D001780:Blood Coagulation Tests; D005171:Factor X Deficiency / Q000150:complications* / Q000473:pathology; D005260:Female; D002836:Hemophilia B / Q000150:complications* / Q000473:pathology; D006801:Humans; D007020:Hypoprothrombinemias / Q000150:complications*; D008875:Middle Aged