Treatment of dermatomyositis with intravenous gammaglobulin

The mainstay of pharmacologic therapy in patients with dermatomyositis is corticosteroids. However, because patients sometimes become refractory to these drugs and because these drugs have potential short- and long-term toxicities, alternate therapy is highly desirable. Therefore, a pilot study was initiated using high-dose intravenous gammaglobulin (IVGG) in the treatment of dermatomyositis.

IVGG was administered to five patients with juvenile dermatomyositis. Prior to IVGG treatment, all patients had persistent muscle weakness despite daily corticosteroids and three patients had developed unacceptable steroid toxicity. Two of the patients had previously developed toxicity while receiving immunosuppressive therapy.

IVGG therapy resulted in improved muscle strength and ameliorated skin rash in all patients. The percentage increase in muscle strength as measured by sphygmomanometry following the 9-month course of IVGG ranged from 56% to 606% in the proximal lower extremities and from 30% to 186% in the proximal upper extremities. Following IVGG therapy, prednisone could be discontinued or the dose reduced in all patients.

This study suggests that IVGG may allow steroid sparing in dermatomyositis and may provide a safe alternative to cytotoxic therapy.