Primary amyloidosis associated with IgD-lambda M-proteinemia

We describe here a case of primary AL amyloidosis associated with IgD monoclonal gammopathy of undetermined significance. A 73-year-old man was referred to our hospital with suspected multiple myeloma due to renal failure and urinary Bence Jones protein. Although serum electrophoresis revealed IgDlambda monoclonal protein, the bone marrow did not showed plasma cell proliferation. Systemic bone survey disclosed no lytic bone lesions. Because the patient had macroglossia and multiple ecchymosis in the face and neck, primary amyloidosis was suspected. Skin biopsy revealed extensive deposition of amyloid which was positively stained by Congo red dye. A diagnosis of primary AL amyloidosis associated with IgD monoclonal gammopathy was made. The patient was also complicated renal failure that eventually needed hemodialysis. To our knowledge, this is the first report of primary AL amyloidosis associated with IgD monoclonal gammopathy with undetermined significance.