- Autoimmune d/o affecting muscles
- Symmetrical proximal weakness of arms and legs
- Develops over weeks to months
- Neck flexor weakness
- No sensory deficits
- Sometimes pain, though not prominent feature
- Dysphagia in 1/3
- Polyarthritis in 45%
- SOB if interstitial lung disease
- Symmetric proximal > distal weakness
- Preserved reflexes
- Dry crackles if interstitial lung disease
- "Mechanics hands": hyperkeratotic, fissured on palms/lateral aspects
- Elevated CK and aldolase
- Often LDH, ast/alt, ANA elevated