Abnormal
bleeding is sometimes observed in patients with
immunoglobulin light chain (
AL) amyloidosis. Although several theories have been proposed regarding the pathological causes of the
bleeding tendency in
AL amyloidosis, many lacked sufficient evidence and full consensus. We conducted a retrospective survey at a single institution to assess
bleeding manifestations, methods for evaluating hematological abnormalities, and treatments for
bleeding in patients with systemic
AL amyloidosis over the past 13 years. The participants were 10 men and 14 women, aged 39-84 years (mean 65 years). The prevalence of
bleeding was 29%. Prolonged prothrombin time (PT), elevated plasmin-α2-antiplasmin complex, and
factor X deficiency were distinctive to the
bleeding group. Two case studies showed that
tranexamic acid was effective for treating this hematological condition. However, two patients with normal PT and activated partial thromboplastin time (APTT) also had a
bleeding manifestation. The rates of administration of coagulation and fibrinolytic tests were relatively low in the non-
bleeding group. Therefore, a close investigation concerning coagulation and fibrinolysis should be performed in every patient with
AL amyloidosis regardless of the PT/APTT values. A more careful, comprehensive, and large-scale study is required to reinforce these findings.