Inflammatory Myositis

Inflammatory myositis describes polymyositis and dermatomyositis. The main feature is muscle inflammation.

Causes and Risk Factors

Gottron's papules

heliotrope rash - violet coloration of the eyelid

Shawl sign - maculopapular rash in mainly sunexposed areas

mechanic's hands - hyperkeratosis and cracking

multiple organs involved: muscles, skin, lungs, heart, GI tract

symmetric proximal muscle weakness

elevated serum muscle weakness

myopathic changes on EMG

characteristic muscle biopsy changes

typical rash with DM, as opposed to PM

Increased incidence of malignancy, which can can occur before, during, or after.