Table 2.

Common imaging findings based on the antibodies.

Anti-ARS Antibody Positive	Anti-MDA5 Antibody Positive
Chronic to subacute onset >> Acute/rapidly progressive	Acute or subacute onset, often rapidly progressive
Distribution along the bronchovascular bundles in the bilateral lower lung fields > diffuse	Diffuse, predominantly in the lower lung fields, or both
Reduced volume of the lower lobes	Peribronchovascular lesion of the periphery of lower lobes, with parallel spread to the pleura
Reticular shadows or consolidation > GGO	Patchy distribution
Good response to treatment but relapses	GGO and consolidation

GGO: ground-glass opacification.