The current diagnosis of SLE is based on the classification criteria of SLE recommended by the American College of Rheumatology in 1997, which are divided into eleven items. After excluding infections, tumors and other connective tissue diseases, SLE can be diagnosed if four of them are met, as follows: 1. erythema of the cheeks: mainly erythema fixed on the cheekbones and the bridge of the nose; 2. discoid erythema: erythema elevated above the skin in the form of flakes, and some old lesions may develop atrophic scarring; 3. photosensitivity: mainly obvious reaction to sunlight, causing rash and itching; 4. It causes rash, itching, etc.; 4. Oral ulcers: ulcers in the mouth or nasopharynx observed by the doctor; 5. Arthritis: mainly non-erosive arthritis, involving more than two joints, with swelling, fluid accumulation or pressure pain; 6. Pluritis: mainly manifested as pleurisy or pericarditis, etc.; 7. Renal lesions: mainly manifested as urine protein 3 plus or 24-hour urine protein ≥ 0.5g, or urine protein ≥ 0.5g. 8. neuropathy: mainly manifested as headache, seizure or mental abnormality; 9. hematological disorders: mainly manifested as hemolytic anemia, leukopenia or thrombocytopenia; 10. immunological abnormalities: manifested as positive anti-double-stranded DNA, positive anti-Sm antibody or positive antiphospholipid antibody; 11. anti-nuclear antibody: at any time and High titers of antinuclear antibodies positive in the absence of drug-induced drug lupus.