Weakly positive antinuclear antibodies mean that you may have an autoimmune disease or a physiologic cause. 1. Autoimmune diseases: antinuclear antibodies have important diagnostic value for many autoimmune diseases, and weak positive antinuclear antibodies are most commonly found in systemic lupus erythematosus, rheumatoid arthritis, and dry syndrome, etc. There are many subclasses of antinuclear antibodies. There are many subclasses of antinuclear antibodies, and the characteristic antibody profiles are different in different immune diseases, so it is necessary to combine with the patient’s symptoms to improve further autoantibody profiling. 2. Physiologic reasons: Antinuclear antibodies can also be detected as weakly positive in some healthy people, especially in the elderly who have low titers of weakly positive antinuclear antibodies. In general, the higher the titer of antinuclear antibody, the greater the correlation with autoimmune diseases. Therefore, weakly positive antinuclear antibody is recommended to consult the Department of Rheumatology and Immunology, and under the guidance of the doctor to further improve the relevant examinations to clarify the diagnosis and early treatment.