Successful withdrawal of systemic IST according to steroid doses at 6 months after second-line treatment. (A) ≤0.3 mg/kg per day vs >0.3 mg/kg per day, (B) ≤0.2 mg/kg per day vs >0.2 mg/kg per day, and (C) ≤0.1 mg/kg per day vs >0.1 mg/kg per day. PDN, prednisone-equivalent steroid doses.