Cutaneous Manifestations of Multiple Myeloma.

Multiple myeloma (MM) is a proliferative disorder of plasma cells which produce abnormal immunoglobulin proteins. Skin involvement is rarely found in this disorder. They are either specific or nonspecific lesions. We report four such interesting patients who presented to us initially with common dermatoses such as leukocytoclastic vasculitis, pyoderma gangrenosum, and vesiculobullous disorders and were subsequently diagnosed to have MM. There were no skeletal involvements or renal function abnormality at the time of presentation. Unusual presentation, nonresponsiveness to conventional therapy, and abnormal blood parameters prompted us to suspect some underlying systemic conditions which were later confirmed to be MM after serum immunoelectrophoresis for M-band and bone marrow biopsy.