Polyneuropathy, papilledema, and plasmacytoma

A 28-year-old woman with a subacute progressive sensorimotor polyneuropathy was found to have a solitary plasmacytoma. Later, she developed bilateral papilledema without evidence of intracranial mass lesion. An IgG lambda spike was found on serum immunoelectrophoresis. The patient was treated with localized radiation to the tumor and later with chemotherapy. Objective clinical improvement of the polyneuropathy began three months after the start of chemotherapy and five months after completion of irradiation to the plasmacytoma. It is essential to do a skeletal bone survey and serum immunoelectrophoresis in all adult patients with a subacute or chronic polyneuropathy.