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 look at the titer, one to several, if the original times called 1:1, then is is 1:2, 1:4, 1:16, 1:32 …. The result of TPPA is generally a positive one, and it can also be quantified to do its titer. In fact, we must look at the RPR to determine whether the patient is currently 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, a course of treatment should be made up if the drug dose is insufficient or the treatment is irregular; a comprehensive physical examination, including neurological and cerebrospinal fluid examination, should be performed for early detection of asymptomatic neurosyphilis and cardiovascular syphilis. If necessary, HIV testing should be performed. Strictly regular observation, including general physical examination and serological follow-up. If the titer tends to increase, treatment should be repeated. Sometimes a positive RPR titer and a positive TPPA at the same time may not indicate that you are definitely having syphilis. 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 test results carefully and to consult more experts. How to determine if syphilis during pregnancy is really syphilis or not, or if it is a false positive, it has to be dynamically observed. The monitoring of syphilis indicators during pregnancy should be done once a month. If the first two months are positive, and after two months it becomes suspicious positive, and then it becomes negative, it means it is false positive. If a child is born to a pregnant woman with syphilis, even a positive in vivo RPR indicator does not indicate that the child has syphilis if the newborn antibodies were given to him by the mother and not a real infection. If the indicator of syphilis RPR in the newborn is even higher than the mother’s, or even higher than four times, the newborn can be determined to have congenital syphilis, which is to be treated. If a pregnant woman is found to be RPR positive at the beginning of her pregnancy, but with very low titers, the child is basically not at risk of congenital syphilis after at least two courses of mother-to-child blockade treatment during the first and second trimesters of pregnancy. A false positive during pregnancy, whether it is TPPA or RPR, appears as an antibody positive and will naturally disappear after a period of time. If a pregnant woman is simply positive for TPPA but continues to be negative for RPR, this means that she has had syphilis before and is now cured. The results of the syphilis test must be combined with the patient’s clinical data to comprehensive analysis, not just based on the laboratory list on the hasty conclusion, the patient should not blindly panic and indiscriminate medical treatment.