Syphilis, RPR Test

Syphilis is a common sexually transmitted infection (STI) caused by the bacteria T. Pallidum (Treponema pallidum).  The disease can be cured with antibiotics if identified during the first two stages of syphilis, and it can become increasingly difficult to cure in its late stages.  

We use a Rapid Plasma Reagin (RPR) test to screen for syphilis. The RPR test searches for antibodies to the substances given off by cells when a syphilis infection damages them. The presence of these antibodies indicates if you have a syphilis infection or not. We not only look for the presence of these antibodies, but we provide you with the concentrated amount of antibodies found.

If your RPR results come back positive, a confirmatory fluorescent treponemal antibody absorption (FTA-ABS) may be performed, depending on which lab you visit. This additional step to confirm a reactive RPR diagnosis helps to eliminate the chances of a false-positive result. Our T. Pallidum test can also confirm a positive syphilis diagnosis like the FTA-ABS test.

What are the symptoms of syphilis?

Syphilis is infamous for being difficult to diagnose without testing. This is because syphilis rarely displays symptoms, and even if it does, they can be so mild that it is easy to confuse it with other things. The symptoms will also come and go, but syphilis will never cure itself.

Syphilis has three stages: primary, secondary, and tertiary.

Symptoms of the primary stage of syphilis include:

• Syphilis sore (chancre) - usually just one. This heals in 3-6 weeks by itself.

Secondary stage syphilis symptoms include:

• Skin rash
• Sores on the mouth, penis, or vagina.
• General ill feeling
• Low appetite
• Hair loss
• Vision changes
• Muscle and joint pain
• Fever

The third and final stage of syphilis, known as the tertiary stage, requires years to develop without treatment. Symptoms include:

• Nervous system damage
• Tumors
• Blindness
• Paralysis
• Death

How long should I wait to take the RPR Test?

Your body needs time to develop the antibodies that this test searches for. If you test before these antibodies can completely develop then you could receive a false negative. The ideal time to test is for syphilis is 3-6 weeks post-potential exposure. 

Who is at risk for syphilis?

Anyone who is sexually active can contract syphilis, but those who do not use protection are even more at risk.

According to the CDC, 57.9% of the syphilis cases in 2017 occurred among men who have sex with men (MSM). Because of this statistic, MSM should consider getting tested more frequently than normal to be safe.  

Pregnant women can pass their syphilis infection on to their children if not discovered and treated. This is known as congenital syphilis, and despite the fact that prenatal syphilis testing is a common practice, over 900 cases of congenital syphilis were reported in 2017. Children born with congenital syphilis may be blind, have facial or other bone deformities. Those who contract syphilis in the womb, are at higher risk of being stillborn.

What do my RPR test results mean?

An RPR test result can be either reactive or nonreactive, depending on if antibodies were detected.

•  A nonreactive RPR result means there were no antibodies to syphilis found in the blood sample. If you have been confirmed as nonreactive and you or your doctor still believe that you are at high risk for syphilis, it is advised to wait three weeks and retest to confirm you did not receive a false-negative result.
• A reactive RPR test result is considered abnormal because antibodies were detected. This could either indicate a current syphilis infection, or the presence of a past infection that has been successfully treated. If an RPR test comes back as abnormal, a quantitative titer test will then be performed to determine the actual concentration of antibodies in the blood sample. If the titer returns a ratio of 1:4 or higher, the CDC then recommends doing a T. Padillum test because both types of tests are needed to confirm an active syphilis infection.

Can I get syphilis again?

Yes, you can get syphilis multiple times. Additionally, getting treated for syphilis once before will not make you less likely to get it again. Having an active syphilis infection actually makes you more likely to contract other STDs like HIV.

Check out our other STD Tests

Go back to see all our STD tests or here are some common ones:

• Comprehensive STD Panel
• Ultimate STD Test Panel
• HIV 4th Generation Duo Antigen/Antibody Test
• HIV RNA Test
• Trichomoniasis Test