[Acquired, non-amyloid related factor X deficiency: A first case associated with atypical chronic lymphocytic leukemia and literature review].

Introduction: Acquired factor X deficiency is in most cases associated with AL amyloidosis. Acquired non-amyloid related factor X deficiency (DNAA-FX) has been exceptionally reported in the literature.

Case Report: We report the first case of acquired, non-amyloid related factor X deficiency associated with atypical chronic lymphoid leukemia in a 66-year-old patient with spontaneous hematomas. After therapeutic failure with polyclonal intravenous immunoglobulins, specific lymphoid malignancy treatment allowed symptoms and coagulation disorder resolution.

Conclusion: DNAA-FX should be considered in case of bleeding events or coagulation disorders during low-grade hematological malignancies. Its occurrence can be considered as a treatment indication to prevent potentially fatal bleeding complications.