The causes of autoimmune diseases include genetic factors, environmental factors, physical factors, drug factors, and pathogen infections. 1. Genetic factors: the occurrence of autoimmune diseases has the tendency of family inheritance. Epidemiologic data show that the occurrence of autoimmune diseases in the family of patients with autoimmune diseases is significantly higher than that in the family of the general population. In addition, the incidence of the same autoimmune disease is much higher in monozygotic twins than in dizygotic twins. Autoimmune diseases have complex genetic characteristics, and polygenic inheritance determines susceptibility to autoimmune diseases. 2. Environmental factors: air pollution, chemical pollutants, etc. are related to the development of autoimmune diseases. 3. Physical factors: Ionizing radiation and ultraviolet radiation are related to autoimmune diseases. 4. Drug factors: certain drugs can cause autoimmune diseases. Studies have found that the renin-angiotensin-aldosterone system has an important association with Th1/Th17-mediated autoimmune diseases. In addition, statins and other drugs are also associated with the development of autoimmune diseases. 5. Pathogen infection: various pathogens associated with autoimmune diseases, including viruses, bacteria and parasites, after invading the body, in addition to direct damage to the body’s tissues and organs, will also cause autoimmune reactions. If you have or suspect that you have autoimmune diseases, we recommend that you consult a regular hospital in time for further diagnosis and treatment as soon as possible.