[Diclonal gammopathy (IgG kappa, IgA lambda) with nephrotic syndrome terminating into IgA lambda myeloma after three years--report of a case].

A 43-year-old man was admitted to our hospital because of legs edema and periorbital edema in Dec. 1983. Laboratory findings showed massive proteinuria (3.7 g/day), Bence Jones protein (BJP) in urine, and hypoproteinemia. Peripheral blood examinations were normal and a bone marrow aspiration showed hypocellularity with slight increase of monocytes and plasma cells. Serum immunoelectrophoresis showed two M-components (IgG kappa, IgA lambda). Serum IgG was 1,690 mg/dl, IgA 379 mg/dl and IgM 160 mg/dl. No remarkable findings were obtained in bone survey, Ga-scintigraphy and rectal biopsy, and a diagnosis of diclonal gammopathy with nephrotic syndrome was made. In Aug. 1986, serum IgA started to increase rapidly with concomitant decrease IgG. He died of pneumonia due to pancytopenia in Dec. 1986, when serum IgG was 450 mg/dl, IgA 1,014 mg/dl, and IgM less than 39 mg/dl. Immunoelectrophoresis showed two M-components (IgG kappa, IgA lambda) in serum and BEP (kappa, lambda), IgG (kappa) and IgA (lambda) in urine. An autopsy showed massive infiltration of myeloma cells which were positive for lambda light chain in bone marrow, suggesting a development of myeloma from a diclonal gammopathy in about 3 years.