The detection of Treponema pallidum involves medical immunoassay methods, in particular the use of new syphilis-specific antigens. Immunological methods and rapid strep test
kits can be used to detect early syphilis infection.
Syphilis is an ancient sexually transmitted disease. The pathogen of human syphilis is Treponema pallidum, also known as P. pallidum. The pathogen is an obligate human parasite, and it is not easy to artificially culture. It is well known that syphilis is a long-term disease and serious harm. It invades the genitals and skin early, and invades all organs of the body, especially the cardiovascular and central nervous system. Syphilis can be divided into acquired syphilis (acquired) and congenital syphilis according to the route of infection. Penicillin has a good effect on syphilis, but it does not prevent TP reinfection.
At present, common methods for syphilis serological testing include rapid plasma reductive loop card experiment (RPR), toluidine red non-heated serum test (TRUST), treponema pallidum gelatin agglutination test (TPPA), and enzyme-linked immunosorbent assay (ELISA). RPR and TRUST examined non-specific antibodies to Treponema pallidum, both of which have poor sensitivity and specificity (false positive and false negative rates of up to 30%). Although the specificity and sensitivity of the TPPA method are high, the source of the natural spirochete antigen used is difficult, expensive, complicated, and the interpretation results are subject to subjective factors, and it is difficult to automate. In recent years, the detection of Treponema pallidum antibodies by the rapid strep test is the most popular.
Most of the currently used rapid strep test kits use the recombinant TpN15 (TP0171), TpN17 (TP0435), TpN47 (TP0574), TpN44.5 (TmpA\TP0768) antigens to detect the corresponding specificity in the serum of patients with syphilis antibody. Although this type of reagent has a high detection rate for the second phase, the specificity is not good. Pregnant women, autoimmune diseases, and chronic persistent hepatitis patients often have false positive results. At the same time, the detection ability of early syphilis infection is poor (only 80% sensitivity to primary syphilis), and the window period is longer. The blood that is missed will become a source of infection and often cause serious consequences. Therefore, finding new specific and sensitive antigens to improve the early detection rate of syphilis is an urgent problem to be solved in this field. Pregnant women, patients with autoimmune diseases, and patients with chronic persistent hepatitis often have false positive results. At the same time, the detection ability of early syphilis infection is poor (only 80% sensitivity to primary syphilis), and the window period is longer. Leaked blood often becomes a source of infection and often has serious consequences. Therefore, finding new specific and sensitive antigens to improve the early detection rate of syphilis is an urgent problem to be solved in this field.