Effect of high-dose intravenous immunoglobulin on amyotrophic lateral sclerosis and multifocal motor neuropathy.

OBJECTIVE: To determine if high-dose intravenous immunoglobulin therapy is effective in improving muscle strength or in arresting the pace of disease progression in patients with rapidly progressive amyotrophic lateral sclerosis. DESIGN: An open-label pilot study of intravenous infusions of high-dose immunoglobulin administered once a month for 3 months in nine patients with classic amyotrophic lateral sclerosis. Selected patients had a rapidly progressive course with signs of worsening noticeably evident every 6 weeks prior to therapy. A patient with multifocal motor neuropathy with conduction block that presented as a lower motor neuron syndrome was concurrently treated to document the efficacy of the same preparation of immunoglobulin in a potentially treatable disease that simulates lower motor neuron syndrome. The efficacy of high-dose intravenous immunoglobulin infusions was assessed by objective measurement of maximum voluntary isometric contraction in all muscle groups of two limbs before and after therapy. SETTING: The Clinical Center of the National Institutes of Health, Bethesda, Md. RESULTS: All patients with amyotrophic lateral sclerosis worsened during the study. By the end of the third month, their mean total muscle scores (megascores) had declined by 71.2 points, from a mean of 369.7 (range, 200 to 605) to 298.5 (range, 130 to 552) points. The pace of progression did not change during the 4-month observation period. In contrast, the patient with multifocal motor neuropathy responded to intravenous immunoglobulin therapy and increased his megascores by 146 points after 3 months. The GM1 antibody titers were normal in all the patients. CONCLUSIONS: High-dose intravenous immunoglobulin, a prohibitively expensive drug, has no apparent therapeutic role in improving the symptoms or arresting the pace of progression in patients with amyotrophic lateral sclerosis. In contrast, multifocal motor neuropathy is an immunopathologically different disease that responds to intravenous immunoglobulin therapy.

A controlled trial of high-dose intravenous immune globulin infusions as treatment for dermatomyositis.

BACKGROUND: Dermatomyositis is a clinically distinct myopathy characterized by rash and a complement-mediated microangiopathy that results in the destruction of muscle fibers. In some patients the condition becomes resistant to therapy and causes severe physical disabilities. METHODS: We conducted a double-blind, placebo-controlled study of 15 patients (age, 18 to 55 years) with biopsy-proved, treatment-resistant dermatomyositis. The patients continued to receive prednisone (mean daily dose, 25 mg) and were randomly assigned to receive one infusion of immune globulin (2 g per kilogram of body weight) or placebo per month for three months, with the option of crossing over to the alternative therapy for three more months. Clinical response was gauged by assessing muscle strength, neuromuscular symptoms, and changes in the rash. Changes in immune-mediated muscle abnormalities were determined by repeated muscle biopsies. RESULTS: The eight patients assigned to immune globulin had a significant improvement in sores of muscle strength (P < 0.018) and neuromuscular symptoms (P < 0.035), whereas the seven patients assigned to placebo did not. With crossovers a total of 12 patients received immune globulin. Of these, nine with severe disabilities had a major improvement to nearly normal function. Their mean muscle-strength scores increased from 74.5 to 84.7, and their neuromuscular symptoms improved. Two of the other three patients had mild improvement, and one had no change in his condition. Of 11 placebo-treated patients, none had a major improvement, 3 had mild improvement, 3 had no change in their condition, and 5 had worsening of their condition. Repeated biopsies in five patients of muscles whose strength improved to almost normal showed an increase in muscle-fiber diameter (P < 0.04), an increase in the number and a decrease in the diameter of capillaries (P < 0.01), resolution of complement deposits on capillaries, and a reduction in the expression of intercellular adhesion molecule 1 and major-histocompatibility-complex class I antigens. CONCLUSIONS: High-dose intravenous immune globulin is a safe and effective treatment for refractory dermatomyositis.