Acquired factor X deficiency in patients with amyloid light-chain amyloidosis: incidence, bleeding manifestations, and response to high-dose chemotherapy.
Acquired deficiency of factor X occurs in patients with systemic amyloid light-chain (AL) amyloidosis, presumably due to adsorption of factor X to amyloid fibrils. Of 368 consecutive patients with systemic AL amyloidosis evaluated at Boston Medical Center, 32 patients (8.7%) had factor X levels below 50% of normal. Eighteen of these patients (56%) had bleeding complications, which were more frequent and severe in the 12 patients below 25% of normal; 2 episodes were fatal. Ten factor X-deficient patients received high-dose melphalan chemotherapy followed by autologous stem cell transplantation. Of 7 patients alive 1 year after treatment, 4 had a complete hematologic response, and all 4 experienced improvement in their factor X levels. One of 2 additional patients with partial hematologic responses had improvement in factor X. Thus, aggressive treatment of the underlying plasma cell dyscrasia in AL amyloidosis can lead to the amelioration of amyloid-related factor X deficiency.
Section of Hematology and Oncology, Department of Medicine, Boston Medical Center, Boston, MA, USA.
E B
EB
Choufani
V
V
Sanchorawala
T
T
Ernst
K
K
Quillen
M
M
Skinner
D G
DG
Wright
D C
DC
Seldin
D000682:Amyloid; D000686:Amyloidosis / Q000150:complications* / Q000453:epidemiology / Q000628:therapy; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001780:Blood Coagulation Tests; D005171:Factor X Deficiency / Q000453:epidemiology / Q000209:etiology* / Q000628:therapy; D005500:Follow-Up Studies; D018380:Hematopoietic Stem Cell Transplantation; D006470:Hemorrhage / Q000209:etiology; D015994:Incidence; D008558:Melphalan / Q000008:administration & dosage; D014182:Transplantation, Autologous; D016896:Treatment Outcome
D000682:Amyloid; D000970:Antineoplastic Agents; C033048:amyloid protein AR, human; D008558:Melphalan