RPR test - non-treponemal screening test that detect antibodies (regain) IgG and IgM to lipid and lip protein material released from damaged cells of patients with syphilis. 

Ant phospholipid antibodies detected by this RPR test, found in 70-80% of individuals with primary syphilis and almost 100% of patients - with secondary and early latent syphilis. In most cases, positive RPR-response observed 7-10 days after the primary chancre or 3-5 weeks after infection. Titers decreased after the secondary stage of syphilis. About 30% of patients with late syphilis are non-reactive for RPR-test. Decrease in the RPR titer of 4 or more times within 1 year after the therapy proves its effectiveness. In 90-98% of cases after treatment of syphilis RPR-test, result is negative. 

The test is not specific. So sometimes, you may experience false-positive reactions. Anti-lipoid antibodies may appear due to not only syphilis or other treponemal infections, but also in response to the development of non-treponemal disease of acute or chronic nature, at which the tissue damage (particularly common in autoimmune diseases). Upon receipt of a positive result in the RPR-test, the patient should be surveyed dermatologist with repeated blood tests using treponemal specific diagnostic test (egg, the reaction of passive hem agglutination TRNA, and revealing specific antibodies to the antigen of Treponema palladium). 

Rare false negative results in the reaction RPR can be eliminated while the appointment of a test TRNA. These two studies are complementary and the combined use of tests, RPR and TRNA is the best option for screening studies for detection or exclusion of syphilis at all stages. 

Indications for analysis. 1. Initial evaluation of suspected syphilis (with confirmation of positive reactions in any treponemal tests). 2. Diagnosis of latent syphilis (with confirmation of positive reactions in the two treponemal tests). 3. A survey of donors (in conjunction with the treponemal tests). 4. Screening. 

Preparation for research: 

Blood sample is desirable to produce an empty stomach. 
Material for the study: serum. 
Method of determining: flocculation test (RPR-antigen, used in sets, is a modification of VDRL antigen). 
In case of detection of anti-cardio lapin, antibody response is given "positive" and comments are the values of the title. In the absence of anti-cardio lapin, antibody response is given "negative". At very low titers given answer is doubtful, it is recommended to repeat the study in 10-14 days. " 

TRNA syphilis (Treponema palladium hem agglutination assay, the reaction of passive hem agglutination) 
Specific diagnostic treponemal test detect antibodies to antigens of Treponema palladium, the causative agent of syphilis. 

TRNA-study can be used as a diagnostic confirmatory test for syphilis, as well as high-selection (screening) test.