High rheumatoid factor may be caused by diseases such as systemic lupus erythematosus, rheumatoid arthritis, etc. Clinical symptoms caused by different diseases vary greatly, for example, patients with rheumatoid arthritis often suffer from swollen joints, morning stiffness, joint pain, etc. Rheumatoid factor is an autoantibody that targets IgG. Rheumatoid factor is a kind of autoantibody with denatured IgG as the target antigen, which should be negative under normal circumstances. Elevated rheumatoid factor has different degrees of positivity for autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, desiccation syndrome, scleroderma, and so on, and the different diseases causing rheumatoid factor will cause the patients to show different clinical symptoms. The common clinical symptoms of SLE patients include rash, hair loss, fever, muscle pain, etc.; rheumatoid arthritis is characterized by joint pain, joint swelling and morning stiffness, etc.; and dry syndrome is characterized by dry mouth, dry eyes, and rampant dental caries. Rheumatoid factor test results should be interpreted by a professional physician, it is recommended that patients with high rheumatoid factor to the rheumatology department of a regular hospital for detailed consultation.