To confirm the diagnosis, highly reliable treponemal tests are used.
In research, specific antigens are used treponem, and more complex and expensive methods are used to detect the antigen-antibody reaction results.
These include immunofluorescence (RIF), passive hemagglutination (RPGA), immunoassay (ELISA), immunoblotting, and immobilization of pale treponem (RIBT) reactions.
Immunofluorescence reaction (RIF)
At RIF, the immune serum, which is linked with a specific antigen treponem and examined by serum, is labeled with a glowing composition (fluorochrome). When a positive reaction is observed, a glow, visible through a luminescent microscope.
Passive hemagglutination reaction (RPAA)
The test is based on agglutination (sticking to the lumps and falling into the sediment) red blood cells (red blood cells), which are fixed antigens of pale treponemy. The reaction occurs only in the presence of antireponemic antibodies. RPAA becomes positive four weeks after the initial infection.
Immunoenzyme analysis (ELISA)
The difference in this method from other serological tests is that the antigen-antibody complex is detected using an anti-virus immune serum labeled with an enzyme. The level of sensitivity of the test is similar to RIF.
This method is one of the most accurate methods for diagnosis of syphilis. At its conducting, bluetreponemy undergoes electrophoresis, and then the processing of separated protein determinants is studied by serum and antibodies, labeled enzymes or radioactive substances.
The reaction of immobilization of pale treponemus (RIBT)
The reaction is based on the immobilization of (pale yellow) treponem antibodies in the blood of patients with syphilis. Positive is the reaction of immobilization from 51 to 100% of pale treponemes.
By means of IBT, false positive results are detected in standard serological tests. However, currently the method is used only for research purposes.
In addition to these methods for the diagnosis of various forms and complications of syphilis, additional studies are conducted (eg, bone radiography, visual examination, hearing, and others).