False positive for syphilis serum reaction

The false positive of the syphilis serum response is that after infection with syphilis, two types of antibodies are produced in the human body, one is an antibody directed against Treponema pallidum, and the other is an antibody directed against lipidoids. Antibodies against lipids are not directly directed against Treponema pallidum, so they are not specific. In addition to infection with syphilis, they suffer from other diseases and changes in physiological conditions. Low titers of antilipid antibodies may also be produced in the body. When syphilis is diagnosed, a syphilis serological test detects both types of antibodies. The RPR test is an experiment to detect lipidoid antibodies; the TPHA is an experiment to directly detect Treponema pallidum. Because RPR is an experiment to detect lipidoid antibodies, rather than directly detecting anti- Treponema pallidum antibodies, there is no specificity, and any disease that can cause the production of lipidoid antibodies can make RPR positive.

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