Severe finger necrosis in antisynthetase syndrome with positive anti-OJ antibodies.

Anti-aminoacyl tRNA synthetase (ARS) autoantibodies are myositis-specific, and patients who test positive for ARS and have common clinical features are usually diagnosed with antisynthetase antibody syndrome (antisynthetase syndrome). Anti-ARS antibodies include histidyl-tRNA synthetase-1 (Jo-1), anti-threonyl (PL-7), anti-alanyl (PL-12), anti-glycyl (EJ), anti-asparaginyl (KS), anti-tyrosyl (Ha), and anti-phenylalanyl (Zo) tRNA synthetases. Among these, anti-isoleucyl tRNA synthetase (OJ) autoantibodies are extremely rare, and patients with these are frequently complicated by interstitial pneumonia. We report the case of an older man with ARS antibody syndrome who tested positive for anti-OJ and anti-Sjögren's-syndrome-related antigen A (Ro-52) antibodies. He had muscle weakness due to myositis and unparalleled rapid and severe finger necrosis. Pulsed prednisolone effectively treated the myositis symptoms and terminated the progression of finger necrosis.