What is an RPR test?

by | Oct 22, 2019 | Blog, News, STD

RPR test Syphilis

As the First Derm AI technology advances, it has become increasingly accurate in detecting visual STDs with accuracy now reaching over 80% including differential answers. Our AI tool has become more useful than ever in providing an answer for skin conditions, and in particular STDs such as syphilis. If syphilis appears in your results then the next step would be a test such as an RPR test.

A rapid plasma regain (RPR) test is a blood test used to screen for syphilis. The test works in similar ways to a test for other STDs – the test detects nonspecific antibodies that your body has been producing to fight the infection.

By performing an RPR test, your doctor is then able to confirm the diagnosis of an active infection that may have been given initially by either checking for visual symptoms or using our AI technology.

Syphilis is a serious infection when untreated and can lead to fatality. It is caused by the spirochete bacterium Treponema pallidum. As with many STDs, the sooner it is treated, the less likely it is to spread and cause complications.

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Do I need an RPR test?

First, if you’re noticing some symptoms described on our syphilis page then the best time to act is now. Our skin image tester will give you more accurate guided answer and has been found to be more accurate than a general physician when testing for visual STDs. The next step would be to speak to your doctor who will likely order an RPR test based on your symptoms.

A Typical user that needs an RPR test

I am 28 years old male. 1-week of symptom. lower scrotum boil with “white heads” in boil, minor decrease in size from one week ago. I was tested for STD’s including syphilis, gonorrhea, HIV and chlamydia and all tests were negative. Urine sample was tested also no signs of irregularity. No pain in area of boil.

Received 2018-05-30 19:56
Given answer 2018-05-30 22:05

Dermatologist Answer
Thank you for using our internet service and sending your case. Based on the information and images of your genital lesion, I can’t rule out that this possibly is SYPHILIS, a sexually transmitted infection caused by a bacteria known as Treponema pallidum. The first sign of infection is usually a firm, painless ulcer or sore known as a chancre, which usually appears at the point of infection in the genital area. The infection can be treated with high doses of penicillin (antibiotics). You don’t tell anything about your sexual history and by the way, some STD-testings may not be reliable. Therefore, I recommend that you see a dermatologist or go to an STD clinic as soon as possible for evaluation and appropriate testing. Until a finale diagnosis, condom use during sexual intercourse is recommended.


How does an RPR test work?

An RPR test measures the antibodies that are present in the blood rather than searching for the bacterium that causes syphilis. This is typical of many STDs and using an RPR test can also effectively verify that antibiotic therapy has been successful – the doctor will be looking for a drop in the antibodies your body creates to fend off syphilis.

The process for an RPR test is relatively simple using a procedure known as venipuncture (put simply, a needle in the vein to extract blood). The test can be done in your doctor’s office and there is no need to fast or take any special measures prior to the test.

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Are there any risks with an RPR test?

Venipuncture is a typical procedure and at most there may be a short, sharp pain initially. Some people may become dizzy during the test, just let your doctor know if you feel any light-headedness – this should only last a few minutes.


RPR Results

The main thing to watch for is a false negative. A normal RPR result may show no antibodies but a doctor cannot completely rule out syphilis simply because there are no antibodies.

Once infected, it can take some time for the immune system to create antibodies. If the infection was recent, the test may not yet show anything. This happens often for a person who is enduring the early or late stages of the infection. However, the RPR test result is nearly always positive for users in the secondary stage of infection (middle).

It’s worth noting that there are also other underlying diseases that can produce false-negative results. One of these diseases could be producing antibodies similar to that of a syphilis infection. A couple of examples are:

The false negative issue is easily remedied by waiting a few weeks before testing again.

Check for Syphilis Today

As with any disease, we always recommend that you are proactive and get checked before it has chance to develop. If you believe you have symptoms that may be similar to syphilis then we recommend you compare with some of the images we have here at First Derm. Alternatively, our skin image searcher has been developed for you to get fast and guided answers on your skin condition. Anonymous and free to use, we recommend you give it a try and speak to your doctor.

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Centers for Disease Control and Prevention. Syphilis. Available at: https://www.cdc.gov/std/syphilis/stdfact-syphilis.htm

Best Medical Degrees. Available at https://www.bestmedicaldegrees.com/.

Daily Mail. Heat map reveals where highest rates of STDs occur in the U.S. – and most are found in the South. Available at https://www.dailymail.co.uk/news/article-2254609/Heat-map-reveals-highest-rates-STDs-occur-U-S–South.html#ixzz4ApD16PTb.

Evaluation of a Multiplex Fully Automated Treponemal and Nontreponemal (Rapid Plasma Reagin) Assay. Arbefeville S, Lynch M, Ferrieri P. Am J Clin Pathol. 2019 Jul 5;152(2):230-236

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