Hyperlipidemia associated with multiple myeloma.

A 70-year-old woman with type IIb therapy-refractory hyperlipidemia was diagnosed as having IgA kappa type multiple myeloma. She had neither a family history nor any other disease known to accompany hyperlipidemia. The serum IgA concentration fell from 3.42 g/dl to 1.24 g/dl following chemotherapy with melphalan and prednisolone, and a concomitant decrease in both the serum cholesterol and triglyceride levels was observed. These serum lipids were positively correlated with the serum IgA concentration (p < 0.001) during the three cycles of chemotherapy. These findings suggest the involvement of the monoclonal protein of IgA in the development of hyperlipidemia in the present case.