Syphilis (RPR)

Syphilis (RPR) Lab Tests and health information

If you're struggling with troubling syphilis symptoms, such as new sores or rashes on your body, testing with Ulta Lab Tests can put your mind at ease.

Name Matches

RPR (Diagnosis) with Reflex to Titer and Confirmatory Testing


Clinical Significance

This is a non-treponemal screening test for syphilis. False positive results may occur due to systemic lupus erythematosus, leprosy, brucellosis, atypical pneumonia, typhus, yaws, pinta, or pregnancy. Monitoring of RPR is helpful in assessing effectiveness of therapy.


False-positive results have been associated in patients with infections, pregnancy, autoimmune disease, old age, Gaucher disease, and malignancy.

Alternative Name(s) 

Premarital RPR,Syphilis Serology Screen, Blood,ART,Rapid Plasma Reagin,Automated Reagin Test

Description: The RPR test is used to determine if a person has been infected with syphilis. An RPR can be used to monitor treatment for syphilis and the effectiveness of syphilis treatment. Syphilis testing is a two-part test. The first round of testing for syphilis is an RPR test. If these results come back positive, a second round of testing will be required. A positive RPR result will be followed by a second method that will be used to confirm the results. If the second syphilis test comes back positive, the affected person will be diagnosed with syphilis. If the second test comes back negative, it could mean that the first test is a false positive and more testing may be necessary.

Also Known As: Rapid Plasma Reagin with Reflex to Titer, Syphilis RPR, Syphilis Titer test

Collection Method: Blood Draw

Specimen Type: Serum

Test Preparation: No preparation required


A positive RPR screen must be followed by a specific treponemal antibody test (e.g., FTA-ABS):

A positive result on the second method confirms the screening result and the affected person is diagnosed with syphilis.

A negative result on the treponemal test may mean that the initial RPR test was falsely positive. Further testing and investigation may be done to determine the cause of the false positive.


False-positive results have been associated in patients with infections, pregnancy, autoimmune disease, old age, Gaucher disease, and malignancy.

When is a Syphilis RPR test ordered?

When a person shows signs and symptoms of syphilis, a syphilis test may be done.

Regardless of symptoms, a person should be tested for syphilis if they:

  • Are being treated for gonorrhea or another sexually transmitted disease?
  • If a woman is pregnant, she should be seen during the first prenatal visit, then again in the third trimester and at the time of delivery if she is at high risk.
  • Are a man who has sex with other males; testing should be done at least once a year or every 3-6 months if the risk is significant.
  • Engages in high-risk sexual behavior, such as having intercourse with several partners without protection.
  • If you have HIV, you should get tested when you're initially diagnosed and then at least once a year after that; if you're at high risk, you should get tested more frequently.
  • Has one or more partners who have tested positive for syphilis
  • Officials from the Department of Public Health have told him or her that he or she has been exposed to an infected partner.

When a person has been treated for syphilis, the CDC recommends doing follow-up testing, such as assessing antibody levels, to ensure that the therapy was successful and the infection was cured.

What does a Syphilis RPR blood test check for?

Syphilis is a bacterial infection caused by Treponema pallidum that is primarily spread during sexual activity, such as by direct contact with a syphilis sore. The majority of common syphilis tests can detect antibodies in the blood that were produced in response to a T. pallidum infection. Some less common methods can be used to locate the bacterium or its genetic components.

Syphilis is easily treated with medications, but if left untreated, it can cause serious health concerns. A mother who is afflicted can convey the disease to her unborn child, which can have serious and even fatal effects for the newborn.

With syphilis, there are numerous stages that can occur:

  • The primary stage of syphilis begins about 2-3 weeks following infection. One or more chancres emerge, usually on the body portion exposed to the chancre of the sexual partner, such as the penis or vaginal area. The chancre, on the other hand, is usually painless and may go unnoticed, especially if it is in the rectum or on the cervix, and it goes away within 4-6 weeks, mending whether or not the infected person is treated.
  • If primary syphilis is left untreated, secondary syphilis can develop anywhere from 6 weeks to 6 months after the chancre initially emerges. It is characterized by a rough, red, and speckled skin rash that appears regularly on the palms of the hands and the bottoms of the feet and does not itch. Fever, weariness, enlarged lymph nodes, sore throat, and body aches are some of the other symptoms that can occur.
  • Secondary syphilis can progress to a latent stage, during which an infected individual has no symptoms but still retains the infection, and this stage can remain for years if left untreated. If left untreated, roughly 15% of persons will develop late, or tertiary, syphilis issues. Bacteria can harm the heart, eyes, brain, neurological system, bones, joints, and practically any other component of the body in these situations. Neurosyphilis is a disease that affects the central nervous system. Tertiary syphilis can linger for years, leading to mental illness, blindness, other neurological issues, heart disease, and death in the ultimate stage.
  • If left untreated, syphilis progresses.

The basic and secondary stages of syphilis are the most contagious. About a third of the approximately 63,000 new cases of syphilis reported to the CDC in 2014 were main or secondary stage syphilis. Eighty-three percent of these cases included guys having intercourse with other men.

Antibiotics, usually penicillin, can be used to cure syphilis. Infections that have been acquired recently can be rapidly healed; however, someone who has been infected for more than a year may require prolonged therapy.

Lab tests often ordered with a Syphilis RPR test:

  • HIV Antibody
  • HIV Antigen
  • Gonorrhea
  • Chlamydia
  • Herpes 1 and 2
  • Trichomonas
  • STD Panel

Conditions where a Syphilis RPR test is recommended:

  • Sexually Transmitted Diseases
  • Syphilis
  • Gonorrhea
  • Chlamydia
  • Herpes 1
  • Herpes 2
  • HIV and AIDS
  • Pregnancy

How does my health care provider use a Syphilis RPR test?

Syphilis tests are used to detect and/or diagnose infection with the bacterium Treponema pallidum, which causes syphilis.

There are a variety of tests to choose from. The most common type of test is an antibody test.

Antibody tests identify antibodies in the blood and, occasionally, in the cerebrospinal fluid. Nontreponemal antibody test and treponemal antibody test are the two types of syphilis tests available. Syphilis screening can be done with any type, but it must be followed by a second test that employs a different approach to confirm a positive result and identify active syphilis:

Antibodies that aren't specifically directed towards the Treponema pallidum bacterium are detected by nontreponemal antibody testing. The body produces these antibodies when a person has syphilis, but they can also be produced in a variety of other situations. Because the tests are non-specific, false-positive findings can be produced by things like IV drug usage, pregnancy, Lyme disease, certain types of pneumonia, malaria, tuberculosis, or certain autoimmune disorders like lupus. A positive screening result must be double-checked with a more detailed test. Nontreponemal testing include the following:

RPR—in addition to screening, this test can be used to track syphilis therapy. Antibody levels are tested for this reason. When an initial test for treponemal antibodies is positive, it can also be used to confirm the existence of an active infection.

VDRL—in addition to blood, this test is largely used to identify neurosyphilis in the CSF.

Antibodies to T. pallidum are detected by treponemal antibody tests, which are blood tests. Because they are extremely specific for syphilis, they are unlikely to produce a positive result in other diseases. Once a person is infected and these antibodies form, they remain in the bloodstream for the rest of their lives. Nontreponemal antibodies, on the other hand, usually vanish within 3 years in a properly treated person. As a result, a positive treponemal screening result must be followed by a nontreponemal test in order to distinguish between an active infection and one that has been successfully treated in the past. FTA-ABS is a treponemal antibody test that is beneficial after the first 3-4 weeks after exposure. It can be used to assess antibodies to T. pallidum in the CSF to assist diagnose neurosyphilis in addition to blood testing.

  • TP-PA—instead of FTA-ABS, this test is sometimes used because it is more specific and has less false positives.
  • Another confirmatory approach is MHA-TP, which is presently used considerably less frequently.
  • Immunoassays—Several automated tests have been developed in recent years, making them useful for screening applications.

What do my Syphilis test results mean?

A negative blood test indicates that there is most likely no infection. A negative screening test, on the other hand, simply states that there was no evidence of disease at the time of the test. Antibodies may not be detected for several weeks following bacterial contact. If a person is aware that he or she has been exposed, or if the risk of infection remains high, additional testing may be required. It is also critical for persons who are at a higher risk of contracting syphilis to get regular screening tests to check for infection.

A particular treponemal antibody test must be performed after a positive RPR or VDRL screen:

The infected person is diagnosed with syphilis once a positive result on the second method confirms the screening result.

A negative treponemal test result could indicate that the initial RPR or VDRL test was incorrectly positive. To discover the reason of the false positive, more testing and investigation may be conducted.

A treponemal antibody test, on the other hand, will be used as an initial test by a healthcare practitioner or laboratory. A positive result indicates the presence of syphilis antibodies in the blood, but because treponemal antibodies stay positive even after an infection is treated, it does not indicate whether the person is now afflicted or has previously been infected. Nontreponemal antibodies found with an RPR, on the other hand, usually vanish after 3 years in a properly treated person. If the initial treponemal test is positive, an RPR can be used to determine whether the infection is active or past. A positive RPR in this scenario would establish that the person has been exposed to syphilis and, if not previously treated, has an ongoing infection or, if treatment occurred more than 3 years ago, possible re-infection.

The results of one or more RPR titers may be used to monitor treatment and/or determine if treatment was successful. Antibodies to syphilis should be decreased after therapy. If the RPR was 1:256 before therapy, a number of 1:16 after treatment would indicate a reduced amount of antibody. The affected person may have a persistent infection or was reinfected if the titer stays the same or rises. The results can also be transformed to a whole number or reported as dilutions.

Nontreponemal antibodies fade away over time after effective treatment, whereas treponemal antibodies remain in the blood for the rest of one's life.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.

Syphilis FTA-ABS (Confirmation for Syphilis RPR test)

FTA-ABS - Treponema pallidum Ab

Clinical Significance

The FTA-ABS is a specific treponemal assay to detect antibody to t. Pallidum. The FTA-ABS becomes reactive 4-6 weeks after infection. Unlike the nontreponemal tests, once the FTA-ABS test becomes reactive, it will remain reactive for many years. Since the reactivity found with the FTA-ABS does not indicate response to therapy, it is not suitable for monitoring treatment. The FTA-ABS test does not distinguish between syphillis and other treponematoses such as yaws, pinta and bejil.

The treponemal antibody test (FTA-ABS) is often used as an initial test. A positive result indicates the presence of syphilis antibodies in the blood, but since treponemal antibodies remain positive even after an infection has been treated, it does not indicate whether the person has a current infection or was infected in the past. Conversely, nontreponemal antibodies as detected with an RPR typically disappear in an adequately treated person after about 3 years. Thus, if an initial treponemal test is positive, an RPR can be performed to differentiate between an active or past infection. In this case, a positive RPR would confirm that the person has been exposed to syphilis and, if not treated previously, has an active infection or, if treatment had occurred more than 3 years ago, possible re-infection.

Alternative Name(s) 

Treponemal pallidum, Fluorescent Treponemal Antigen, Syphilis

Beta-2-Glycoprotein 1, apolipoprotein H, is a cofactor in antiphospholipid antibody binding and is the critical antigen in the antiphospholipid antibody syndrome. Beta-2-Glycoprotein 1 Antibody is more specific than cardiolipin antibody that may express reactivity in patients with syphilis and other infectious diseases.

Beta-2-Glycoprotein 1, apolipoprotein H, is a cofactor in antiphospholipid antibody binding and is the critical antigen in the antiphospholipid antibody syndrome. Beta-2-Glycoprotein 1 Antibody is more specific than cardiolipin antibody that may express reactivity in patients with syphilis and other infectious diseases.

Beta-2-Glycoprotein 1, apolipoprotein H, is a cofactor in antiphospholipid antibody binding and is the critical antigen in the antiphospholipid antibody syndrome. Beta-2-Glycoprotein 1 Antibody is more specific than cardiolipin antibody that may express reactivity in patients with syphilis and other infectious diseases.


  • CBC (includes Differential and Platelets)
  • Antibody Screen, RBC with Reflex to Identification, Titer, and Antigen Typing 
  • ABO Group and Rh Type
  • RPR (Diagnosis) with Reflex to Titer and Confirmatory Testing
  • Hepatitis B Surface Antigen with Reflex Confirmation*
  • Rubella Antibody (IgG), Immune Status
  • If Antibody Screen is positive, Antibody Identification, Titer, and Antigen Typing will be performed at an additional charge (CPT code(s): 86870, 86886, 86905).
  • If RPR screen is reactive, RPR Titer and FTA Confirmatory testing will be performed at an additional charge (CPT code(s): 86593, 86780).
  • If Hepatitis B Surface Antigen is positive, confirmatory testing based on the manufacturer's FDA approved recommendations will be performed at an additional charge (CPT code(s): 87341).

The major proteins seen in the serum are albumin and globulin-the latter being primarily alpha 1 and alpha 2 globulin, beta globulin and gamma globulin. Albumin accounts for more than 50% of the total serum proteins. The albumin to globulin (A/G) ratio has been used as an index of disease state, however, it is not a specific marker for disease because it does not indicate which specific proteins are altered. The normal A/G ratio is 0.8-2.0. The A/G ratio can be decreased in response to a low albumin or to elevated globulins. Total globulins may be increased in some chronic inflammatory diseases (TB, syphilis) multiple myeloma, collagen disease, and rheumatoid arthritis. Decreased levels are seen in hepatic dysfunction, renal disease and various neoplasms.

Most Popular

Description: RF is a blood test that is measuring the amount of rheumatoid factor that is present in the blood’s serum. It is used along with other tests to diagnose rheumatoid arthritis.

Also Known As: RF Test, Rheumatoid Arthritis Factor Test

Collection Method: Blood Draws

Specimen Type: Serum

Test Preparation: No preparation required

When is a Rheumatoid Factor test ordered?

When a person has RA signs and symptoms, an RF test may be ordered. Pain, warmth, swelling, and morning stiffness in the joints are common symptoms, as are nodules under the skin and, if the disease has progressed, signs of enlarged joint capsules and cartilage and bone loss on X-rays. When the first RF test is negative but the symptoms persist, the RF test may be repeated.

A cyclic citrullinated peptide antibody test may be ordered along with RF or if the RF result is negative to help diagnose RA in someone who has joint inflammation but does not yet fit the criteria for RA.

Additional autoimmune-related tests, such as an ANA, as well as other markers of inflammation, such as a CRP and Sed Rate, as well as a CBC to examine blood cells, may be ordered in addition to the RF test.

What does a Rheumatoid Factor blood test check for?

The autoantibody rheumatoid factor is an immunoglobulin M protein produced by the body's immune system. Autoantibodies attack a person's own tissues, mistaking them for "foreign" tissue. While the biological role of RF is unknown, its presence can be used to detect inflammatory and autoimmune activities. This test identifies and quantifies radiofrequency in the bloodstream.

The RF test is an important tool in the diagnosis of rheumatoid arthritis. A RF test will be positive in about 80% of people with RA. RF, on the other hand, can be found in persons with a range of different illnesses, including as Sjögren syndrome, as well as persistent bacterial, viral, and parasite infections, and some malignancies. It can be noticed in patients who have lung, liver, or kidney disease, and it can also be detected in a tiny percentage of healthy persons.

Lab tests often ordered with a Rheumatoid Factor test:

  • Cyclic Citrullinated Peptide Antibody
  • ANA
  • Sed Rate
  • C-Reactive Protein
  • Immunoglobulins

Conditions where a Rheumatoid Factor test is recommended:

  • Rheumatoid Arthritis
  • Autoimmune Disorders

How does my health care provider use a Rheumatoid Factor test?

The rheumatoid factor test is used to diagnose rheumatoid arthritis and to distinguish it from other types of arthritis or diseases that generate similar symptoms.

While the clinical picture is critical in the diagnosis of RA, some signs and symptoms, particularly in the early stages of the disease, may not be present or follow a predictable pattern. Additionally, the signs and symptoms may not always be easy to distinguish because people with RA may also have other connective tissue disorders such Raynaud phenomenon, scleroderma, autoimmune thyroid problems, and systemic lupus erythematosus and present symptoms of these disorders. When RA is suspected, the RF test is one of several tools that can be used to aid determine a diagnosis.

What do my Rheumatoid Factor test results mean?

The results of the RF test must be interpreted in the context of a person's symptoms and medical history.

The presence of large amounts of RF in persons with symptoms and clinical indications of rheumatoid arthritis indicates that they are likely to develop RA. Higher RF levels are associated with a worse prognosis and more severe illness.

A negative RF test does not rule out the possibility of RA. Around 20% of persons with RA will have very low levels of RF or none at all. In these circumstances, a positive CCP antibody test can be utilized to confirm RA.

Sjögren syndrome, systemic lupus erythematosus, sarcoidosis tuberculosis, syphilis, HIV/AIDS, hepatitis, scleroderma, infectious mononucleosis, cancers such as leukemia and multiple myeloma, or disease of the liver, lung, or kidney may all produce positive RF test These other disorders are neither diagnosed or monitored with the RF test.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.

The Tissue Plasminogen Activator assay is used to detect disorders of the fibrinolytic system.

Clinical Significance
VDRL, Serum - The serum VDRL test is an aid in the diagnosis of syphilis. The predictive value of a reactive VDRL is increased when combined with a treponemal-specific test such as FTA or TP-PA. A reactive VDRL test on CSF, free of blood or other contaminants, usually suggests past or present syphilis infection of the central nervous system.

Syphilis is an unwanted intruder that has hung around the human species for several thousand years. It's a sexually transmitted infection that appears in different stages. If it's not treated early, the consequences can be life-threatening.

Syphilis tests are the key to early diagnosis, treatment, and recovery. But how can you avoid catching syphilis? Is it curable? How long will symptoms last?

Let's take a closer look at syphilis testing to answer these questions and more.

What Is Syphilis?

Syphilis is a sexually transmitted disease (STD). According to the Centers for Disease Control, it is common, and the infection rate has been increasing in recent years. The Treponema pallidum bacterium causes syphilis.

Syphilis is one of the infectious diseases that a pregnant woman can pass on to her unborn child, known as congenital syphilis.

Risk Factors for Syphilis

Syphilis is almost always spread through sexual contact. During sex, transmission occurs through coming in contact with an infected person's sore.

The most common ways of contracting syphilis are through:

  • Unprotected sex
  • Sex with multiple partners
  • Men who have sex with men
  • Already having an HIV infection

All forms of sexual activity can put you at risk of catching syphilis. Men who have sex with men are at the highest risk of catching syphilis.

Causes of Syphilis

Syphilis is a bacterial infection. When an uninfected person comes into contact with a chancre, an ulcer on the genitals, they can catch the disease. This typically happens through the mucus membranes or minor cuts on the body.

What Are the Signs and Symptoms of Syphilis?

Syphilis has four main stages if left untreated. It can be hard to diagnose syphilis without screening tests, as it can look like other diseases.

Primary Stage

Syphilis first shows itself with a single chancre - a small painless ulcer. This can appear on the penis, scrotum, vagina, anus, or mouth. This is highly contagious and even kissing can spread the disease at this stage. 

Although a single chancre is common, sufferers can get many sores. If untreated, it will develop into the secondary stage.

Secondary Stage

The secondary stage shows up with skin rashes and lesions in the mouth, vagina, or anus. The skin rashes can appear on any part of the body. They may be painless, but are rough and have a red appearance. 

Other symptoms include:

  • Headaches
  • Swollen glands
  • Lesions in the groin, mouth, or under the arms
  • Muscle aches
  • Weight loss

As with the primary stage, these symptoms will pass in time. But the body cannot cure itself of syphilis. If you do not get treatment, it will move into the latent or tertiary stage.

Latent Syphilis

Once the secondary stage is over, the syphilis infection may lie dormant for a period of time. This stage can last for years.

Tertiary Syphilis

Tertiary syphilis can occur many years after the initial infection. The bacteria now start to affect organ systems, such as the liver, heart, vascular system, or joints. It can also affect the brain and the nervous system.

At any stage in the infection, syphilis can turn into neurosyphilis or ocular syphilis. These forms affect the nervous system and eyes respectively.

How Is Syphilis Diagnosed?

Syphilis is diagnosed using three methods. First, a physical examination checking the outward symptoms of the disease.

Secondly, syphilis tests will be run. Positive results on a syphilis blood test will show whether you have an active infection or have had syphilis in the past. Finally, if you have a chancre, your doctor may take a sample of fluid for testing.

The Lab Tests to Screen, Diagnose, and Monitor Syphilis

The key screening test for syphilis is the RPR (Monitor) test. This looks for the presence of antibodies and can detect syphilis in people who have the disease. This can also be used for monitoring the disease and detecting reinfection in the future.

Another test that is often used in conjunction with RPR is the FTA-ABS #4112. This test is not suitable for monitoring the effectiveness of treatment. However, it can be useful for initial diagnosis.

Frequently Asked Questions About Syphilis and Lab Testing for Syphilis

There are lots of rumors and stories online about syphilis. The most frequently asked questions about syphilis and syphilis lab tests include:

  • What should you not do if you have syphilis?

If you have syphilis, you should avoid any activity that could pass it on to another person. This would include having unprotected sex. You should also avoid using recreational drugs.

  • Is syphilis 100% curable?

It is possible to rid the body of the bacteria that causes the syphilis infection. In this way, it is 100% curable. That said, the treatment to clear the infection will not reverse the damage the condition has already done.

  • How long does it take for syphilis to go away after treatment?

If syphilis is detected early, it can be treated with a single injection of penicillin. If your doctor suspects that you have more long-term syphilis, a longer and more potent course of treatment may be needed. You will need to have further syphilis tests to check whether the infection has been cured.

Get Answers Fast With Syphilis Tests from Ulta Lab Tests

The only accurate way to know if you have this disease is through syphilis tests. They are quick, with results coming back in 2-4 days. Syphilis lab tests can help you know what you're dealing with, so you can start the right treatment as soon as possible.

Benefits of Syphilis Lab Testing with Ulta Lab Tests

Ulta Lab Tests offers syphilis tests that are highly accurate and reliable so you can make informed decisions about your health. Here are a few great things to love about Ulta Lab Tests:

  • You'll get secure and confidential results
  • You don't need health insurance
  • You don't need a physician's referral
  • You'll get affordable pricing
  • We offer a 100% satisfaction guarantee

Order your syphilis lab tests today and your results will be provided to you securely and confidentially online in 24 to 48 hours for most tests.

Take control with Ulta Lab Tests today!