Subcutaneous immunoglobulin in treating inflammatory neuromuscular disorders

Intravenous immunoglobulin administration has long been used in the treatment of autoimmune neuromuscular disorders. Immunoglobulins may be administered by intramuscular, intravenous or subcutaneous routes.

This is a report on the long-term clinical follow up of six patients with inflammatory neuromuscular disorders, that is, three chronic inflammatory demyelinating polyneuropathy (CIDP), one multifocal motor neuropathy (MMN), one inclusion body myositis (IBM) and one myasthenia gravis (MG), treated with subcutaneous immunoglobulins for a mean of 3.25 years.

One MMN and two CIDP patients received a weekly dose of subcutaneous immunoglobulins equivalent to intravenous immunoglobulin. One CIDP patient received a 50% dose reduction, the IBM patient received a 30% reduction and the MG patient a 20% reduction. The lower dose chosen in the majority of patients was based not only on clinical effects, but also on studies of primary immunodeficiency syndromes. One patient with CIDP showed clinical fluctuation, which was successfully treated with an adaptation of the dose of subcutaneous immunoglobulins, while the remaining patients with neuromuscular disorders had a stable clinical course for 2 years. No serious side effects were observed.

Our results suggest that subcutaneous immunoglobulins can be an attractive alternative therapy in autoimmune neuromuscular disorders.