Home›VDRL-RPR (Rapid Plasma Reagin)

Content created by

Written by

BDS

Reviewed by

Dr. Hitesh Tiwari

MD Pathology, MBBS

Want to know more?
Read our Editorial Policy

VDRL-RPR (Rapid Plasma Reagin)

Also known as Syphilis Screening Test, Syphilis Detection Test, Syphilis Serology

₹149

You need to provide

Blood

This test is for

Male, Female

Test Preparation

No special preparation is required.

Understanding VDRL-RPR (Rapid Plasma Reagin)

What is VDRL-RPR (Rapid Plasma Reagin)?

The VDRL-RPR (Rapid Plasma Reagin) is a blood test used to detect syphilis, a sexually transmitted disease (STD). It detects the presence of antibodies produced by the body in response to the syphilis infection. This test is used for initial syphilis screening and monitoring the effectiveness of treatment in individuals diagnosed with the disease.

Syphilis is a bacterial infection caused by the Treponema pallidum bacterium. The VDRL-RPR (Rapid Plasma Reagin) test helps screen for syphilis in individuals who present with symptoms suggestive of syphilis, such as small and painless sores near the site of infection, skin rash, fever, swollen lymph glands, hair loss, headaches, muscle aches, tiredness, etc. It may also be used to screen individuals who are at high risk, such as sexually active individuals, pregnant women, and people with other STDs. This test also helps monitor the effectiveness of syphilis treatment by measuring changes in antibody levels over time.

The VDRL-RPR (Rapid Plasma Reagin) test is non-treponemal, meaning it does not directly detect the bacteria but rather detects antibodies called reagin, which are produced by the body in response to the cellular damage caused by the bacteria causing syphilis. A positive test result indicates the presence of reagin antibodies, suggesting a current or past syphilis infection. In contrast, a negative test result indicates no detectable reagin antibodies, suggesting the absence of syphilis.

Apart from syphilis, reagin antibodies can also be found in other infections such as tuberculosis, malaria, viral pneumonia, and other autoimmune diseases. Hence, the VDRL-RPR (Rapid Plasma Reagin) test results should be interpreted in conjunction with other specific tests and clinical findings to diagnose syphilis definitively.

The VDRL-RPR (Rapid Plasma Reagin) doesn’t require you to fast or stop taking medications. If your doctor wants you to make an exception, they will inform you before your test. However, avoid alcohol consumption before the test. Drinking alcohol within 24 hours of the test can give a false-negative result.

Test result ranges may vary across laboratories. Abnormal test results require an expert interpretation; therefore, never try to self-medicate at home based solely on these results, and always consult a doctor for a proper understanding of the test results. The insights from this test help the doctor tailor an appropriate treatment plan.

What is VDRL-RPR (Rapid Plasma Reagin) used for?

The VDRL-RPR (Rapid Plasma Reagin) test is done:

To screen for syphilis in people having symptoms of sexually transmitted infections.
To screen people who are at risk of exposure to syphilis, such as having another STD or HIV infection, homosexual men having a sexual partner diagnosed with syphilis, or indulging in high-risk sexual activity.
To screen pregnant women for syphilis.
To monitor the ongoing treatment response for syphilis.

What does VDRL-RPR (Rapid Plasma Reagin) measure?

The VDRL-RPR (Rapid Plasma Reagin) test looks for antibodies (specific proteins) that react to syphilis in the blood. This means the test doesn't find the actual bacteria that cause syphilis. Instead, it looks for antibodies against substances given off by cells that have been harmed by the bacteria. Antibodies are a specific type of protein produced by your immune system to fight off any invaders, such as bacteria, viruses, or toxins. Detecting these antibodies can help your doctors know if you have syphilis. Untreated syphilis can spread to your eyes, blood vessels, heart, and brain. But it can be easily cured if treated in the early stages.

Interpreting VDRL-RPR (Rapid Plasma Reagin) results

Interpretations

Negative: A negative ("non-reactive") RPR test result is compatible with a person not having syphilis.

The result of this test can be “positive” or “negative”. However, there are some cases where the results can be false positive or negative.

A negative ("non-reactive") RPR test result suggests that a person is not having syphilis. However, the body does not always produce antibodies specifically in response to the syphilis bacteria, so the test is not always accurate. The false-negatives test result may occur in people with early- and late-stage syphilis. Because of that, other tests are required to confirm the results.

A false positive RPR (which means positive results in the absence of syphilis) can be encountered in infectious mononucleosis, tuberculosis, leprosy, malaria, lupus erythematosus, vaccinia, and viral pneumonia. Pregnancy, autoimmune diseases, and narcotic addictions may give false-positive results. Also, this test may give false-positive results in pinta, yaws, bejel, and other treponemal diseases.

RPR test is also used to monitor treatment response. Treatment response is generally indicated by a 4-fold (2-tube dilution) reduction in rapid plasma reagin (RPR) titer (e.g., from 1:32 to 1:8). For proper interpretation of RPR results, titers should be obtained using the same testing method and, preferably, at the same testing laboratory.

Failure of nontreponemal test titers to decline 4-fold within six months after therapy for primary or secondary syphilis may be indicative of treatment failure. Patients whose titers remain serofast should be reevaluated for HIV infection.

Answers to Patient Concerns & Frequently Asked Questions (FAQs) about VDRL-RPR (Rapid Plasma Reagin)

Frequently Asked Questions about VDRL-RPR (Rapid Plasma Reagin)

Q. Why is the VDRL-RPR (Rapid Plasma Reagin) test done?

The VDRL-RPR (Rapid Plasma Reagin) test is done to screen syphilis when you experience signs and symptoms like body rashes, mild fever, hair loss, sore throat, weight loss, swollen glands, muscle pains, headaches, etc. This test is also a routine test in prenatal care during pregnancy. It also helps monitor treatment response in known cases of syphilis.

Q. Does this test pose any risks?

A VDRL-RPR (Rapid Plasma Reagin) test is a normal blood test with no risks. However, since this test involves a needle prick to withdraw the blood sample, in very rare cases, a patient may experience increased bleeding, hematoma formation (blood collection under the skin), bruising or infection at the site of needle prick. Most of these symptoms go away in a day or two.

Q. What are the stages of syphilis?

There are four stages of syphilis that include primary, secondary, latent and tertiary syphilis. At the primary stage of syphilis, you might notice single sore or multiple sores in or around the genital areas and lips or mouth in the initial stage. During the secondary stage, you may have rough and reddish brown skin rashes and sores in your mouth, and genital area.The latent stage of syphilis there are no visible signs or symptoms. Without treatment, you can continue to have syphilis in your body for years. In the tertiary stage, syphilis can affect many different organ systems including heart, blood vessels, brain and nervous system. Tertiary syphilis is very serious and would occur 10–30 years after your infection began.

Q. What if my VDRL-RPR (Rapid Plasma Reagin) is positive?

A positive test result means you may have syphilis. Consult your doctor and discuss your test reports. You may be asked to go for a confirmatory test with a more specific test for syphilis, such as FTA-ABS.

Q. What causes false-positive VDRL-RPR (Rapid Plasma Reagin) test results?

False-positive VDRL-RPR (Rapid Plasma Reagin) test results can occur in certain acute and chronic infections, autoimmune diseases such as tuberculosis, malaria, viral pneumonia, lupus, rheumatoid arthritis, HIV, lyme disease, during pregnancy, and after vaccination.

Q. What do you mean by false-negative test RPR results?

False-negative test results mean that the RPR test is negative in the presence of syphilis infection. The body does not always produce antibodies specifically in response to the syphilis bacteria, so the test is not always accurate. False-negatives may occur in people with early and late stage syphilis. Hence, other tests are required to confirm the results.

Q. Is there any cure available for syphilis?

Yes, syphilis is curable with the right antibiotics. However, treatment cannot reverse the damage that might have been caused by the infection. If syphilis is treated too late, it can permanently damage your heart and brain even after the infection is gone.

Q. When is syphilis contagious?

Syphilis is most contagious during the first two stages and the early latent stage. It can spread through sexual routes, therefore, it is known as sexually transmitted disease (STD). It can enter the body through the genitals, mouth, or broken skin. A pregnant woman infected with syphilis can pass it on to her baby.

Q. How can syphilis be prevented?

The best and the most certain method of prevention of syphilis infection is to avoid sexual contact or only to maintain sexual contact with one faithful partner who is not infected.