1, non-syphilis spirochete antigen serologic test (a), syphilis spirochete antigen serologic test (a) clinical significance: (1) health or exclude syphilis; (2) confirmed history of sexual contact / history of sexual partner infection, rechecked after 4 weeks of contact; (3) there are reports in the literature, in patients with cured stage I syphilis, about 15% to 25% in 2 to 3 years after the syphilis spirochete antigen serologic test can be turned negative. 2, non-syphilis spirochete antigen serologic test (+), syphilis spirochete antigen serologic test (a) clinical significance: (1) non-syphilis spirochete antigen serologic test false positive. If the titer ≤ 1:8, there is a possibility of viral hepatitis, measles or malaria, mostly within 6 months to negative; (2) If the titer > 1:8, or even 1:64, seen in collagenous diseases, autoimmune system diseases (such as autoimmune hemolytic anemia, rheumatoid disease, lupus erythematosus, Hashimoto’s thyroiditis, etc.), narcotic addiction, pregnant women, etc. 3, non-syphilis spirochete antigen serologic test (a), the clinical significance of syphilis spirochete antigen serologic test (+): (1) early syphilis. Syphilis spirochete infection 1 to 2 weeks IgM antibody production, 4 weeks IgG antibody production, and reactive element 5-7 weeks production, so syphilis spirochete infection early can appear this pattern, more than 4 weeks retest non-syphilis spirochete antigen serologic test can be positive. (2) It has been reported that 1% of false positive syphilis spirochete antigen serologic tests can exist, such as lupus erythematosus, which can make FFA-ABS false positive, and infectious mononucleosis, which can make TPHA false positive, and some syphilis spirochete antigen serologic tests in leprosy patients can also be positive. It has also been reported that in addition to the three aforementioned diseases, rheumatoid arthritis, mixed connective tissue disease, scleroderma, cirrhosis, lymphosarcoma, genital herpes, diabetes mellitus, heroin addiction, and pregnancy can also cause false-positive spirochete antigen serologic reactions, most of which are in cases of systemic lupus erythematosus, see literature. (3) Prozone phenomenon (prozone phenomenon). Clinical manifestations of second-stage syphilis and RPR test appears weakly positive or negative, then the serum will be diluted to do quantitative tests, and then positive results, 1% to 2% of patients with second-stage syphilis can appear this phenomenon. The reason for this is that there are too many anti-cardiolipin antibodies in the serum, either because of closed antibodies or because of non-specific inhibitors. (4) The patient has previously suffered from syphilis and has undergone systematic and standardized anti-syphilis treatment, indicating that the syphilis has been cured and is a previous syphilis infection. (5) About 34% of patients with stage III syphilis can have this pattern. For this reason, in addition to the serological test, it is necessary to check whether there are signs of stage III syphilis to determine whether it is stage IV syphilis. 4, non-syphilis spirochete antigen m serum test (+), the clinical significance of syphilis spirochete antigen serum test (+): (1) a history of sexual contact / history of sexual partner infection, with clinical manifestations of syphilis, can be diagnosed as syphilis; based on the time of infection, signs, respectively, diagnosed as stage I syphilis (infectious), stage II syphilis (highly infectious) or stage III syphilis (weak or no infectious, but the tissue destruction, sexual contact Generally non-infectious, if pregnancy can still be transmitted to the fetus. (2) A history of sexual contact/partner infection, without signs of syphilis or signs have disappeared, can be diagnosed as latent syphilis, also known as latent syphilis. Depending on whether the duration of infection is more than 2 years, the diagnosis can be early latent syphilis (infectious) or late latent syphilis (weak or no infectiousness), respectively. (3) Sero-fixation reaction (sero-resistance), also called serotolerance. After systematic syphilis treatment, most of the non-syphilis spirochete antigen serologic tests can turn negative, but there are a few patients whose non-syphilis spirochete antigen serologic test titer gradually decreases to a certain level and then no longer decreases, but remains at a low titer level for a long time. A positive syphilis serology test is an important basis for the diagnosis of syphilis, but it is not the only basis for the diagnosis of syphilis. When a clinician sees a patient suspected of having syphilis, he or she should first prescribe a non-syphilis spirochete antigen RPR serologic test, and then prescribe a syphilis spirochete antigen serologic test after a positive test result, or prescribe both a non-syphilis spirochete antigen serologic test and a syphilis spirochete antigen serologic test, and analyze the test results, clinical manifestations and epidemiological history to make a careful diagnosis.