There are more skin diseases, for routine skin diseases, if it is allergic skin disease, you can check the blood routine, liver and kidney function, blood sugar, blood lipid, and even some can check the rheumatism aspect. For more persistent skin diseases, further examination may be needed, such as coagulation function, skin tuberculosis problems. For lupus erythematosus with a rash, if you need to go for a diagnosis, you can go for ENA or immunoglobulin, which are different tests. There are also sexually transmitted diseases that need to be checked for syphilis and HIV or herpes virus, herpes 1 and herpes 2 virus. So there are a lot of different tests for skin diseases and different diseases may check different aspects.