Key Clinical MessageIn a patient with anti-aminoacyl tRNA synthetase antibody and anti-OJ antibody syndrome, interventions likes warming, prostaglandins, and antiplatelets failed. However, prednisolone pulse treatment rapidly halted disease progression. Patients with mild interstitial pneumonia, myositis, and extremity necrosis should be promptly considered for anti-synthetase syndrome and receive immunosuppression after ruling out other causes.AbstractAnti-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-Sj & ouml;gren'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. A purple color change was noticed in the second to fifth fingers of the left hand on admission (Fig. 1-A). After admission, the color of the patient's fingers changed from purple to black, indicating necrosis (Fig. 1B). After prednisolone pulse administration, a purple transition zone appeared in the necrotic area of the fingers, which subsequently ceased expanding (Fig. 1C). After pulse therapy, necrosis did not progress (Fig. 1D).image
