Acquired Factor X Deficiency in Systemic Light Chain Amyloidosis: Factor X Recovery after Bleeding Complications, Splenectomy, Chemotherapy and Remission

Aim: Acquired factor X deficiency is one of the more frequent coagulation abnormalities (8.7 to 14 %) in systemic light chain amyloidosis with about half of the patients presenting bleeding symptoms. The therapeutic options are replacement of factor X with plasma products, removal of the factor X -binding amyloid deposits (splenectomy) or chemotherapy. We report on an adult male patient with acquired factor X deficiency who presented severe bleeding complications. The course of factor X activity after splenectomy, chemotherapy and administration of prothrombin complex concentrate (PCC) is reported.

Methods: We report a case of a 75-years-old male patient who was diagnosed with severe haemostatic abnormalities. Coagulation screening revealed an INR of 6.6 and the factor X activity was reduced to 2 %. Traumatic splenic rupture with intraabdominal bleeding necessitated splenectomy followed by daily administration of 3,000 IU PCC. Histopathologic examination of the removed spleen established amyloidosis. Two days after splenectomy, the patient presented lower gastrointestinal bleeding in the context of a gastrointestinal infection and a right hemicolectomy was performed. After two cycles of chemotherapy neither organ manifestations of amyloidosis nor pathological free light chain assay results were present. No further bleeding episodes occurred. However, the follow up examination showed an increase of factor X activity (111.1 %) to normal levels (77-128%) after two years.

Results: A recovery study with PCC was performed. After a single dose of 40 IU/kg, factor X activity level increased from 3.8 % to 12 % and the INR decreased from 2.9 to 1.7. Within 2 hours the factor X activity level dropped to 5.8 % and the INR was 2.1. In addition, the factor X antigen-levels rise from 6.9 % to 12.5 % within one hour after PCC administration and only decrease to 11.4 % after two hours.

Conclusion: Even after splenectomy, chemotherapy and following remission of systemic light chain amyloidosis, the results demonstrate a rapid decrease of factor X after PCC administration. We suspect elimination and adsorption of factor X to areas of amyloid deposition other than the spleen going undetected by imaging techniques. The estimate bleeding risk and efficacy of treatment is still difficult to say. However factor X recovered after 1 year of time of remission.