Myositis and Myopathies
Polymyositis 
 • Progressive, symmetric muscle weakness 
 • Elevated CK, +Anti-Jo, +Anti-Mi2
Dermatomyositis 
 • Progressive, symmetric muscle weakness, rash 
 • Elevated CK, +Anti-Jo, +Anti-Mi2
Polymyalgia Rheumatica 
 • Pain and stiffness in proximal joints, Fever, No muscle weakness
 • Elevated ESR, Normal CK, associated with temporal arteritis
Inclusion Body Myositis
 • Slow onset, asymmetric muscle weakness
 • Normal or mildly elevated CK, Biopsy: inclusions, rimmed vacuoles
HIV myopathy 
 • Proximal muscle weakness 
 • Elevated CK, Detectable HIV viral load
Drug-induced myopathy
 • Alcohol, Steroids, Statins, Cocaine, Chloroquine, Colchicine, Anti-retrovirals, Gemcitabine
Lupus Myopathy 
 • Diffuse muscle pain and/or joint aches
 • +ANA, +Anti-Smith, +Anti-dsDNA, Myositis: elevated CK (uncommon 5-15% of lupus myopathy)

VA Joint Chiefs @BostonChiefs

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