There are two types of syphilis serology test nonspecific nontreponemal serology and specific treponemal serology. Treponemal tests detect antibody to t pallidum proteins. Performance of treponemal tests for the diagnosis of. Vdrl test and its interpretation pubmed central pmc. If treponemal serology is to be interpreted correctly a sexual history is needed. Non treponemal test titers in early latent syphilis are similar to those of secondary syphilis. Hence, the serologic diagnosis of syphilis requires the detection of 2 types of antibodies nontreponemal antibodies and treponemal antibodies. Consensus statement on the clinical implications of a positive syphilis serology test in the context of a previous negative syphilis point of care test 2 rationale. Now, with the availability of enzymelinked immunosorbent.
However, non treponemal test is necessary to detect patients. There are 2 different types of serologic tests classified based on the type of antigen the antibodies are directed against. Pathogenic nichols strain from rabbit testicles is fixed to a slide. Canada, laboratory diagnosis, nontreponemal tests, serology. Nonspecific tests detect antibodies that bind to antigens that are, or are similar to, those expressed by treponema pallidum or expressed on host tissues during infection. Most rapid syphilis tests are made in a dipstick or cassette format. Because these tests measure the hosts antibody response to non treponemal. Therefore, the results of a non treponemal assay, such as the rapid plasma reagin. The nontreponemal tests such as rapid plasma reagin test rpr or the. Treponemal syphilis specific antibodies remain in the blood for life, whereas non treponemal non syphilis specific antibodies typically clear the blood after approx.
This nontreponemal antibody rpr is the reflex confirmation test to the syphilis antibody screen. All serological tests are positive at secondary stage and sensitivity for all tests including vdrl test which is approximately 100%. The delaware public health laboratory performs a highly sensitive but somewhat non specific rapid screening test and a highly sensitive and specific confirmatory test for syphilis serology testing. Comparative study of treponemal and nontreponemal test. If both rpr and tppa tests fail to confirm a reactive screening result, another treponemal test, fluorescent treponemal antibody absorption ftaabs has been. During this test reagins, the non treponemal antibody or antibodies react with a phospholipid, called cardiolipin to form aggregation. I think the lab from health department may confirmed the specific treponemal test and the result was non reactive that was meant that you were not get syphilis disease. Maternal evidence of syphilis includes reactive non treponemal and treponemal syphilis serology tests or positive darkfield or other direct test of suspicious lesions. The recent introduction of pointofcare tests for syphilis has raised the issue of the clinical.
Guidelines for evaluation and management of neonates exposed. The etiological agent, treponema pallidum, cannot be cultured, and there is no single optimal alternative test. Traditionally syphilis serology is a twostep algorithm where the patients serum is initially screened with a non treponemal test e. Syphilis serologic testing guidelines for interpretation. For non treponemal tests, rpr or usr were consistently performed by 54% of laboratories while the vdrl was performed by about 38%. Syphilis serologic testing guidelines for interpretation 1. This non treponemal antibody rpr is the reflex confirmation test to the syphilis antibody screen. Historically, the serologic testing algorithm for syphilis included an initial nontreponemal screening test, such as the rapid plasma reagin rpr or the venereal. Pdf characterization of treponema pallidum particle.
Proper serologic diagnosis of syphilis in adults requires both a treponemal test and a non. The traditional algorithm begins with a non treponemal assay, and if it is positive, the treponemal test is done. Comparative study of treponemal and nontreponemal test for. A nonspecific nontreponemal test, such as the rapid plasma reagin rpr test or venereal disease reference. However, recently laboratories in nova scotia have moved to using the reverse algorithm. Suggested reporting language for syphilis serology testing aphl.
Please discuss all csf serology reqeusts with the oncall virology registrar or consultant. The australian therapeutic goods administration has registered the alere determine syphilis tp for use as a point of care syphilis test in australia. Nontreponemal antibody regional medical lab test directory. Nontreponemal tests detect antibodies directed against lipoidal antigens, damaged host cells, and possibly from treponemes. Specific populations to target for screening include men. Ftaabs may remain active for life, even following adequate therapy. A new reflex testing algorithm for syphilis screening. Historically, the serologic testing algorithm for syphilis included an initial non treponemal screening test, such as the rapid plasma reagin rpr or the venereal disease research laboratory vdrl tests. Serologic testing for syphilis with traditional and reverse algorithms. What is the turnaround time for syphilis serology test results. Evaluation of the whocdc syphilis serology proficiency. The paradigm in syphilis testing has recently shifted in many centers to screen with a treponemal antibody test, reflexing to a nontreponemal test if the treponemal antibody test is positive. The advantage of non treponemal tests is that they are quantitative and can therefore be used to monitor response to treatment as the tests become negative with successful therapy.
In contrast, treponemal tests look for antibodies that are a direct result of the infection thus, antitreponeme igg, igm and to a lesser degree iga. The reverse serology algorithm detects early, primary, and treated syphilis that may be missed with traditional screening. A recent metaanalysis reported sensitivities and specificities comparable to those of laboratorybased treponemal tests. Direct examination of clinical specimen by darkfield microscopy or fluorescent antibody testing of sample. Both rpr and trust are non treponemal standard status diagnostic tests for syphilis, with similar levels of sensitivity and specificity in qualitative assays. Pdf syphilis serology in patients with primary syphilis and. The non treponemal tests such as rapid plasma reagin test rpr or the venereal disease reference laboratory test are the most commonly used test for screening of syphilis in the blood centers in india. Both types of tests can be performed on one sample of patient serum. Syphilis serology testing 3 treponemal assays, that either directly detect the pathogen or antibodies to the pathogen, have also evolved over the course of the 20th century and now 21st century. Confused by syphilis serology youre not the only one. Specimen collection procedure for syphilis serology. The venereal disease research laboratory test abbreviated vdrl test is a syphilis serology blood test and was developed by harris, rosenberg, and riedel in 1946.
The findings from this study will help inform the selection of the most appropriate second treponemal test for patients with initially discordant treponemal and nontreponemal serology, and selection of an automated treponemal test when the reverse sequence algorithm is used for a laboratory diagnosis of syphilis. Specimen collection procedure for syphilis serology testing. The advantage of non treponemal tests is that they are quantitative and can therefore be used to monitor response to treatment as the tests become negative with. Serological testing is the most frequently used approach in the laboratory diagnosis of syphilis. May 22, 2019 both rpr and trust are non treponemal standard status diagnostic tests for syphilis, with similar levels of sensitivity and specificity in qualitative assays. Syphilis serological testing cleveland clinic laboratories.
In addition to a thorough history a comparison blood test is usually required. In individuals with a positive serum treponemal antibody, csf serology may guide the diagnosis of neurosyphilis. Nontreponemal tests are an indirect method in that they detect biomarkers that are released during cellular damage that occurs from the syphilis spirochete. Screening with a non treponemal test alone is not recommended because of the potential for false negative results as a result of the prozone phenomenon. It is based upon the reactivity, both igm and igg, of sera from patients with syphilis to non specific cardiolipincholesterollecithin antigens. This is a confirming test for syphilis since it tests specifically for antibodies in the patients serum made in response to the syphilis spirochete, treponema pallidum. Non specific or non treponemal serological test to detect reagin, utilized as. Laboratory diagnostic testing for treponema pallidum.
This feature of treponemal serology makes it very useful for patients and doctors to have documentation of complete treatment for syphilis. The current non treponemal assays are non specific for syphilis. Clinical indications a reactive syphilis igg result indicates that a person has. May 22, 2019 the specific treponemal test for syphilis syphilis tp cmia is available to all health care providers but is not designed to be a screening procedure and thus is only performed when required for proper patient management.
Non treponemal serologic tests for syphilis include vdrl venereal disease research laboratory test and rpr rapid plasma reagin test. The serological tests most commonly used to screen for the disease are the. Guidelines for serological testing for syphilis sexually. There are two types of syphilis serology test non specific non treponemal serology and specific treponemal serology. Recent trends in the serologic diagnosis of syphilis. Unlike nontreponemal assays, which with few exceptions are currently manual, automated assays require far less operator interaction, are easier.
Syphilis usually diagnosed by serology nontreponemal e. Vdrl flocculation test for the detection of nontreponemal. Mar 27, 2012 however, one then needs to take a treponemal test to confirm that increased cardiolipin is in fact a result of a syphilis infection. This is because treponemal tests eg, eia, mfi, or fluorescent treponemal antibodyabsorbed. Consensus statement on the clinical implications of a positive syphilis serology test in the context of a previous negative syphilis point of care test 1 introduction. Need both non treponemal rpr or vdrl and treponemal test tppa, ftaabs, eia, cia to make syphilis diagnosis treponemal tests can remain positive for life. The traditional algorithm using a nontreponemal test ntt followed by a treponemal test tt remains the standard in many parts of the world. Serology tests cannot differentiate between these treponemal infections. A positive rpr or vdrl screen must be followed by a specific treponemal antibody test e. The serological diagnosis of syphilis requires the detection of two distinct antibodies, heterophile. Nonspecific non treponemal antibody screening tests i. An initial screening with a treponemal serology test is followed by a non treponemal rapid plasma reagin rpr test and a treponemal test, treponema pallidum particle agglutination tppa. Serologic testing for syphilis arlington scientific. Many new diagnostic methods for syphilis have been developed, using specific treponemal antigens and novel formats, including rapid pointofcare tests, enzyme immunoassays, and chemiluminescence assays.
Performance of treponemal tests for the diagnosis of syphilis. The laboratory diagnosis of syphilis pubmed central pmc. Syphilis health check faq california department of. Traditionally syphilis serology is a twostep algorithm where the patients serum is initially screened with a nontreponemal test e. Complexities in the diagnosis of syphilis continue to challenge clinicians. The old version of this type of test was the vdrl venereal disease research laboratory test but the more modern and reliable equivalent test is the rpr rapid plasma reagin test. Over the 8year interval, participating laboratories performed a total of six types of tests. The ftaabs test fluorescent treponemal antibody absorption test for syphilis is an example of an indirect fluorescent antibody procedure. Non treponemal serologic tests for syphilis include vdrl venereal disease research. Laboratory diagnosis and interpretation of tests for syphilis.
A nontreponemal test ntt is a blood test for diagnosis of infection with syphilis. Screening for syphilis with the treponemal immunoassay. Stands for fluorescent treponemal antibody absorption test. It detects the igm and igg antibodies to lipoidal material released from the damaged host cells, as well as to lipoproteinlike material and possibly cardiolipin released from the treponemes. A drawback to non treponemal tests is that the level decreases with time. Consensus statement on the clinical implications of a. The non treponemal tests such as rpr or the vdrl test measure the hosts response to non treponemal antigens such as cardiolipin and lecithin released from the damaged host cells, as well as lipoproteinlike material released from the. The rapid plasma reagin rpr test is a macroscopic, nontreponemal flocculation card test used to screen for syphilis. Guidelines for evaluation and management of neonates. This treponemal test performs quite well when used for sera found to be positive on screening, less well to confi rm the presence of negative sera.
Syphilis serology an overview sciencedirect topics. Fact sheet and frequently asked questions faq syphilis health check shc facts. However there are important distinctions between currently available non treponemal test and the rapid treponemal tests as shown in text. Guidelines for evaluation and management of neonates exposed to syphilis babies born to mothers with positive syphilis tests are at risk for congenital syphilis. Treponemal serology can leave one unsure of diagnosis and management. Serum is preabsobed with reiter strain non pathogenic to enhance specificity make sure negative values stay negative by preventing anti treponemal ab that are non specfic to t. This approach might be more attractive to laboratories that have high testing volumes and where the manual labor involved with nontreponemal tests is no longer appropriate for laboratory workflow and staffing needs.
The non treponemal test is a good followup indicator because the titer reflects the activity of the disease. This is also used to check the progress of treatment for active syphilis patients. Confirmation of the diagnosis is through serologic testing. A positive treponemal test will likely be followed by a non treponemal test to confirm a diagnosis. Serology technical leader page 3 of 28 controlled versions of department of forensic biology manuals only exist electronically on the forensic biology network. As no single test is able to diagnose active syphilis, a combination of treponemal and nontreponemal. Methodist and childrens hospitals, omaha, ne, changed its screening protocol from using a non treponemal test rpr first to instead using a treponemal test a syphilis igg enzyme immunoassays eia first see table 1. Non treponemal tests such as the rpr can be considered rapid tests as they can provide a result in less than 10 minutes. Suggested reporting language for syphilis serology testing. The dual poc test detected nontreponemal antibody in all cases of untreated disease but was. Nov 01, 2011 syphilis screening in the us has traditionally involved a non specific, nontreponemal anticardiolipin serological test eg, rapid plasma reagin rpr or venereal disease research laboratory vdrl with subsequent confirmation of positive results by a specific treponemal test eg, treponema pallidum particle agglutination tppa or the. Non specific or non treponemal serological test to detect reagin, utilized as screening test only, not diagnostic. Non specific tests detect antibodies that bind to antigens that are, or are similar to, those expressed by treponema pallidum or expressed on host tissues during infection.
Jan 15, 2011 with the increasing implementation of treponemal specific eias or cias as firstline syphilis screening tests in clinical laboratories, health care providers will inevitably be faced with patients who have positive results on a treponemal specific screening test, yet have negative results on nontreponemal tests. These commercial kits are however expensive and practitioners may rather want to choose a cheap test such as the serum turbidity test. However, one then needs to take a treponemal test to confirm that increased cardiolipin is in fact a result of a syphilis infection. In north america, many unsuspected cases are discovered by laboratory testing. General introduction to serological testing 5 p a g e radial immunodiffusion tests are commercially available for the accurate measurement of immunoglobulins in the serum of neonates. Serological tests for acquired syphilis in immunocompetent. Syphilis testing, new and old, rapid and not so rapid. The reactivity of a non specific reagin rpr test and a specific treponemal ftaabs test were determined in 21 patients with primary syphilis, 430 patients with proven non treponemal genital. The mainstay of diagnosis for treponema pallidum infections is based on nontreponemal and treponemal serologic tests.
A negative result on the treponemal test may mean that the initial rpr or vdrl test was falsely positive. Types of syphilis serology tests medical health tests. Rpr or usr, vdrl, tppa or tpha, elisa, ftaabs and rapid treponemal tests any type. The serological tests most commonly used to screen for the disease are the non treponemal and treponemal tests. Jan 08, 2020 the rapid plasma reagin rpr test is a macroscopic, non treponemal, flocculation card test. The non treponemal tests are reactive in secondary syphilis almost without exception, and usually at titers of 16 or greater regardless of the test method used. Novel pointofcare test for simultaneous detection of. In contrast to the non treponemal tests, treponemal test reactivity will persist following treatment in approximately 85% of the cases often for the. Following treatment, it should show a regular decline until it becomes negative or stabilizes at a low level treponemal test tt remains the standard in many parts of the world.