Bleeding tendency caused by the deposit of amyloid substance in the perivascular region.

A 55-year-old woman, who had systemic amyloidosis associated with multiple myeloma, had sudden development of hematomas of her lip and upper eye lid. There was no evidence of deterioration of multiple myeloma, thrombocytopenia nor deficiency of coagulation factors. Biopsy specimen showed the deposit of amyloid substance in the dermis and perivascular region. The bleeding tendency in this patient with myeloma was likely due to the deposit of amyloid substance in the vascular wall; improvement was achieved with administration of hemostatic agents.