In 2009, the ACR published new revised criteria for the classification of SLE. This criterion was compared with the 1997 ACR revision, in which butterfly erythema and discoid erythema were changed to acute or subacute cutaneous lupus manifestations and chronic cutaneous lupus manifestations, which is more comprehensive than in the past because the skin lesions of SLE can be diverse; non-scarring alopecia was included as one of the criteria, and instead of light allergy; the meaning of arthritis in SLE was further clarified, and there must be inflammatory synovitis manifestation rather than simple arthralgia. In the immunological indexes, it is emphasized that if anti-Ds-DNA antibody is detected by ELISA, it should be higher than the laboratory reference standard twice; anti-cardiolipin antibody detection should be higher than the normal level by more than two times, and β2GPI, complement and hemolytic anemia with negative Coombs test are added. In fact, the immunological indicators were more refined. The importance of renal pathology was emphasized in the conditions for confirming the diagnosis, such as renal pathology confirming lupus nephritis, as long as there is positive ANA or anti-dsDNA to confirm the diagnosis; in addition, on the basis of 4 or more clinical and immunological indicators to diagnose SLE, at least 1 clinical indicator and 1 immunological indicator were included. The following criteria are attached. Clinical criteria: 1. acute or subacute cutaneous lupus manifestations; 2. chronic cutaneous lupus manifestations; 3. oral or nasopharyngeal ulcers; 4. non-scarring baldness; 5. inflammatory synovitis with swelling or pressure pain in 2 or more peripheral joints with morning stiffness; 6. plasmacytitis; 7. renal lesions: at least 500 mg protein/24 hours using the urine protein/creatinine ratio (or 24-hour urine protein) 8. neuropathy: vitiligo, psychosis, polyneuritis, myelitis, peripheral or cranial neuropathy, encephalitis (acute psychotic state); 9. hemolytic anemia; 10. leukopenia (at least 1 cell count < 4.0×109/L) or lymphopenia (at least 1 cell count < 1.0×109/L); thrombocytopenia (at least 1 cell count < 1.0×109/L) thrombocytopenia (at least 1 cell count < 100×109/L). Immunological criteria: 1. ANA titer higher than laboratory reference standard (LRR); 2. Anti-dsDNA antibody titer higher than LRR (2 times higher than LRR by ELISA); 3. Positive anti-Sm antibody; 4. Antiphospholipid antibody: positive lupus anticoagulant/false positive syphilis serology test/anti-cardiolipin antibody more than 2 times the normal level or elevated anti-β2GPI medium titer or higher. 5. reduced complement: C3, C4, CH50; 6. no hemolytic anemia, but positive direct Coombs test. Confirmation criteria: 1. Kidney pathology confirmed lupus nephritis with ANA or anti-dsDNA positivity; 2. 4 or more of the above clinical and immunological indicators were met (at least 1 clinical indicator and 1 immunological indicator were included). The sensitivity of the criteria was 94% and specificity 92%.