Table 1.

Clinical Features of Myositis-Related Interstitial Lung Diseases

Variable	Anti-MDA-5 DM	Anti-synthetase Syndrome	Other Myositis-Related ILD
Myositis-specific antibodies	Anti-MDA-5	Anti Jo-1, anti-PL7, anti-PL12, anti-OJ, anti-EJ, anti-KS, anti-Ha, and anti-Zo	Anti-PM-Scl, anti-R052, and anti-Ku
Muscle disease	Typically amyopathic or hypomyopathic	Myositis in 50%-90%; typical presentation with proximal muscle weakness	Myositis in 37%-49%; mixed pattern including proximal myopathy and myalgia
Skin disease	Ulceration and palmar papules specific to MDA-5; other DM skin manifestations: mechanic’s hands, heliotrope rash, Gottron’s papules, shawl sign	Mechanic’s hands, heliotrope rash, Gottron’s papules, shawl sign	Mechanic’s hands, subcutaneous edema, swollen hands, calcinosis, sclerodactyly, telangiectasia, malar rash, photosensitivity
ILD	Typically rapidly progressive	Typically chronic or subacute	Mixed
Frequency of ILD	50%-90%	66%-90%	25%-61%
Other clinical features	Arthritis (60%), fever (60%)	Arthritis (60%), fever (25%), Raynaud’s phenomenon	Arthritis (77%-94%), Raynaud’s phenomenon (53%-78%)

DM = dermatomyositis; ILD = interstitial lung disease; MDA-5 = melanoma differentiation-associated protein 5.