CRP and Oral ulcer: Among the items, age, SLE disease duration, epilepsy, fever, serositis, oral ulcers, alopecia, anemia, interstitial lung disease, pulmonary hypertension, IgM, IgA, SLEDAI-2K score, infection, hypoalbuminemia, microscopic hematuria, proteinuria, creatinine, urea nitrogen, LDH, ESR, and abnormal elevated CRP were selected.