[Systemic amyloidosis associated with IgD-λ multiple myeloma]

We describe here a case of systemic amyloidosis associated with IgD multiple myeloma. A 59-year-old man was admitted to our hospital in April 2009, because of macroglossia and swelling in both wrists and fingers. He had difficulty moving his limbs and was aware of peripheral neuropathy. Skin biopsy revealed extensive deposition of amyloidosis, which was positive by Congo red staining. Laboratory findings were as follows: serum electrophoresis revealed IgD λ monoclonal protein, and Bence-Jones protein was detected. Monoclonal IgD protein had a concentration of 727 mg/dl, and a bone marrow aspiration revealed 49.6% of plasma cells. These findings led to a diagnosis of IgD multiple myeloma with systemic amyloidosis. The patient was treated with MP (melphalan and methylprednisolone), high-dose dexamethasone and VAD therapy (vincristine, adriamycin and dexamethasone), but systemic amyloidosis progressed, and his general condition deteriorated. Coexistence of IgD multiple myeloma and systemic amyloidosis is rare, and accumulation of case reports is needed to gain a better understanding of this condition.