Intravenous Immune Globulin Therapy in Dermatomyositis

Dermatomyositis is a heterogeneous syndrome with several associated antibodies, such as those against transcription intermediary factor 1-γ (anti–TIF-1γ), melanoma differentiation-associated gene 5 (anti–MDA-5), nuclear matrix protein 2 (anti–NXP-2), and small ubiquitin-like modifier–activating enzyme (anti-SAE). Each of these antibodies is referred to by neurologists and rheumatologists by its acronym for convenience, 1 and each is associated with distinct clinical and histopathological features. 2 More than 30 years ago, dermatomyositis was thought to be caused by complement-mediated microangiopathy, but there is evidence that the microvasculopathy and skin and muscle damage associated with dermatomyositis are due primarily to toxicity from pathways mediated by type I . . .