Mixed connective tissue disease is a diffuse connective tissue disease that manifests clinically as damage to the skin, joints, muscles, and organs and is characterized by laboratory tests that reveal high titers of antinuclear and antiribonucleoprotein antibodies. The pathogenesis of the disease is not clear, but it is believed that the genetic susceptibility is influenced by external factors such as environment and infection, resulting in the production of a series of autoantibodies and damage. Women account for about 80% of patients with the disease, and the clinical symptoms are complex and non-characteristic, mainly include: 1) skin manifestations: dorsal hand swelling, Raynaud’s phenomenon, photosensitivity, etc.; 2) muscles and joints: polymyositis, arthralgia, etc.; 3) cardiopulmonary manifestations: pericarditis, myocarditis, pulmonary fibrosis, pleurisy, etc.; 4) gastrointestinal system: esophageal dilatation, esophageal reflux, hepatosplenomegaly, etc.; 5) nervous system: aseptic meningitis, seizures, etc. 5, neurological system: aseptic meningitis, seizures, episodic vascular headache, psychiatric symptoms, etc.; 6, hematological system: leukopenia, anemia, hyperglobulinemia, etc. The treatment of this disease is symptomatic, non-steroidal anti-inflammatory drugs for pain, hormones, immunosuppressants, biological agents, etc. to control the activity and development of the disease (please consult a specialist in a regular hospital for specific medication). The prognosis of this disease is relatively good because the involvement of important organs is relatively small.