[IgD-lambda type multiple myeloma associated with IgG-kappa type benign monoclonal gammopathy].

A 76-year-old man was admitted to Kisen hospital because of lumbago and chest pain. Laboratory examinations revealed a chronic renal failure with marked elevation of the serum BUN (48.8 mg/dl) and creatinine levels (8.2 mg/dl). The serum electrophoresis demonstrated a hypergammaglobulinemia with M peaks. An immunoelectrophoresis demonstrated monoclonal IgD-lambda and IgG-kappa proteins in the serum, and lambda-type Bence Jones protein in the urine (0.4 g/day). Bone marrow smears revealed an abnormal proliferation of atypical plasma cells (43%). A systemic X-ray examination of the skeletal system showed systemic osteoporosis without punched out lesion. The patient was diagnosed as having IgD-lambda type multiple myeloma and IgG-kappa type benign monoclonal gammopathy by quantifying concentration of two M proteins (1,160 mg/dl in IgD, 1,179 mg/dl in IgG, respectively). A combination chemotherapy with melphalan and prednisolone was administered monthly for multiple myeloma, and hemodialysis for the renal failure was performed 3 times a week. A marked improvement of his laboratory findings including a diminution of the serum IgD-lambda M-protein was obtained. On the other hand, IgG-kappa M-protein level was unchanged. Two M-protein levels showed a different behavior after the combination chemotherapy. Although the patient died of congestive heart failure, the partial remission of multiple myeloma has been maintained for 16 months with chemotherapy.