Differential diagnosis of localized and systemic amyloidosis based on coagulation and fibrinolysis parameters

Abstract

Background: A simple assay that can discriminate between localized and systemic amyloidosis is needed. Methods: Coagulation and fibrinolysis parameters were measured in subjects with active or progressive systemic amyloidosis (Group A; 9 patients), systemic amyloidosis in complete remission (Group B; 6 patients), localized AL amyloidosis (Group C; 6 patients), monoclonal gammopathy of undetermined significance (Group D; 5 patients), chronic glomerulonephritis with proteinuria (Group E; 22 patients), or glomerulonephritis in complete remission (Group F; 11 patients). Results: No significant differences were noted between Group A and the other groups in the international normalized ratio of prothrombin time, activated partial thromboplastin time, and levels of antithrombin and plasminogen. Levels of thrombin–antithrombin (TAT) complexes, fibrinogen, fibrinogen degradation product d-dimers, and plasmin-α2–plasmin inhibitor complexes (PIC) were significantly elevated in Group A. All patients that showed TAT complexes, fibrinogen, and PIC levels greater than 4.2 ng/mL, 399 mg/dL, and 1.4 μg/mL, respectively, had active or progressive systemic amyloidosis. All patients with TAT complex levels less than 3.6 ng/mL, fibrinogen levels less than 355 mg/dL, and PIC levels less than 0.9 μg/mL had localized AL amyloidosis. Conclusion:Analyses of TAT complexes, fibrinogen, and PIC can be used to differentiate localized AL amyloidosis from systemic amyloidosis.

Keywords::

• Thrombin–antithrombin complex (TAT)
• fibrinogen
• plasmin-α2–antiplasmin inhibitor complex (PIC)
• localized amyloidosis
• systemic amyloidosis

Declaration of Interest: The authors have no conflict of interest to disclose.This work was supported by a grant (to H. I.) from the Amyloidosis Research Project of the Ministry of Health, Labour and Welfare of Japan (Director: Dr. Yukio Ando).