A controlled study of intravenous immunoglobulin in demyelinating neuropathy with IgM gammopathy

Abstract

Eleven patients with demyelinating polyneuropathy associated with monoclonal IgM antibodies were randomized to receive IVIg or placebo, monthly, for 3 months in a double-blind study. After a washout period, they crossed over to the alternate therapy. Response was gauged by evaluating muscle strength, sensation, and neuromuscular symptoms at baseline, after 3 months, and at treatment's end. After IVIg therapy, the strength improved in only 2 of 11 patients, by 28 and 38.5 points from baseline, and declined after placebo. In 1 other patient, the sensory score improved by 13 points. Antibody titers to MAG/SGPG or gangliosides did not appreciably change. We conclude that IVIg has only a modest benefit to not more than 18% of patients with IgM paraproteinemic demyelinating neuropathy.