PRB1 and arthritic joint disease: However, in adults with IIM, positivity for antisynthetase, Antimelanoma differentiation–association gene 5 (MDA‐5), anti‐Ku, anti‐Pm/Scl, and anti‐Ro52 antibodies, as well as mechanic’s hands, arthritis or arthralgia, and ulcerating lesions, were associated with an increased risk of ILD [7].