Syphilis is a very complex sexually transmitted disease, except for AIDS, which is syphilis, one of the points is the interpretation of the laboratory report, syphilis laboratory report is very simple, that is, RPR and TPPA, but the dynamic monitoring of the trend of changes is very learned. Usually patients who have syphilis have two main types of antibodies that are positive, one is non-syphilis spirochete antibody and the other is syphilis spirochete specific antibody. The former is tested by RPR or TRUST, and the latter is tested by TPPA or TPHA. Once infected with syphilis, both RPR and TPPA will be positive in succession. How to look at the syphilis test results, RPR is generally to see the titer, one to several, if the original times called 1:1, then is 1:2, 1:4, 1:16, 1:32 ……, are multiples of the relationship. TPPA results are generally a positive, can also be quantified to do its titer. In fact, we must look at the RPR to determine whether the patient is now suffering from syphilis, the time of infection and disease, and the regression of syphilis after treatment. For example, if a patient with syphilis has an RPR of 1:128 before treatment and becomes 1:8 after treatment, or is negative, that would indicate a good outcome. It is common to see separate labs that are positive for TPPA and negative for RPR in clinical practice. If a person has TPPA first and is infected with syphilis, the test will soon be done and TPPA is positive, RPR may be negative, but soon RPR will also become positive, and there is another situation where TPPA will persist, so at this time TPPA only indicates a positive, indicating infection, and the observation indicator must be RPR. If the RPR is negative and the test is repeated after a period of time, it means that the person has been infected with syphilis and has been cured before; if the RPR is positive and the TPPA is positive, it means that the person is probably suffering from syphilis now. But there is a part of people, whether after treatment, or not after treatment, RPR titer down to a certain level, 1:1, 1:2, 1:4, down to this level when not down, no matter how the treatment, repeat many times different programs of treatment, but also has been maintained low titer positive, is the so-called serum fixation phenomenon. Whether there is syphilis or not, whether it is infectious or not, this needs to be considered carefully. In principle, if it is after regular anti-syphilis treatment, the syphilis pathogen is cleared in the body, even if the indicator is positive, it does not indicate infectiousness. For such patients, if the drug dose is insufficient or treatment is irregular, a course of treatment should be made up; a comprehensive physical examination, including neurological and cerebrospinal fluid examination, should be performed for early detection of asymptomatic neurosyphilis and cardiovascular syphilis. HIV testing should be performed if necessary. Strictly regular observation, including general physical examination and serum follow-up. If the titer tends to rise, treatment should be repeated. Sometimes a positive RPR low titer and a positive TPPA at the same time are indicators that sometimes do not indicate that you are definitely having syphilis now. If the RPR titer is very high, and even the trend of dynamic monitoring is still increasing, and the TPPA is positive, this situation confirms that you are suffering from syphilis, and that you have just been infected with syphilis for a short period of time. The test results should also consider false positives. Some immune diseases, some tumors, or diseases of the elderly can also lead to false positives, as well as physiological states, pregnant women can have false positives for syphilis, and generally speaking, the titer of RPR is not high. There is a lot of confusion in this area, and it involves family harmony, so it is really important to read the results of the tests carefully and to consult with experts.