Syphilis Question

[smith2006]

Hello Dr. HHH, Thanks you very much for your help. This forums is great help.

       5 years ago I have unprotected oral sex with pros (I am the one receving). My question is can blood test SYPHILIS/RPR (VDRL) be able to detect if I have syphilis??? Some website said can get false negatives with the RPR in late stage syphilis??? Which test do you remember to take for acurate result and does not give false negative for exposure 5 years ago??? Thanks you very much for your help doctor.

[H. Hunter Handsfield, M.D.]

It  takes 6-8 weeks for the RPR to become positive.  After that, there is no realistic risk of a false negative test; there is only a small, theoretical risk of a false negative result.  If an RPR is negative, you can be sure you don't have active syphilis.  Anyway, syphilis is rare in commercial sex workers in most of the US; and although it can be acquired by oral sex, it is uncommon; and the chance you had syphilis without noticing a sore on your penis is very low.  (When primary syphilis is asymptomatic, generally it s because the chancre--the sore of primary syphilis--is hidden, like inside the vagina or rectum.  But that's really not possible when the penis is exposed.

In other words, the combination of low risk to start, no penile sore, and negative RPR collectively provide rock-solid evident you didn't catch syphilis.  You don't need any additonal testing.

Good luck--  HHH, MD

[David20]

I have read somewhere on the website is here its I copy from the website I just have read The screening test is most valuable in middle stage syphilis, as it will most likely be positive during this time. During early and late stage syphilis, the test may be falsely negative. Additional testing may be needed before ruling out syphilis. Is that true RPR blood test for syphilis maybe false negative if a person in late stage. Since my exposure for 5 years ago if I Have syphilis can RPR blood test for syphilis accurate without false negative?? Thanks DR.

[David20]

For example, If a person has syphilis for 6 years can a RPR blood test indicate that he is positive?? Or 6 years its very long for RPR blood test to test if he is positive??? I just take a test for syphilis and its negative. My biggest worry is that the RPR gave false negative result since its 6 years ago. Can you tell me if a person got Syphilis can RPR test gave false negative??? Thanks you very much doctor.

[David20]

smith2006 and david20 are the same person?? Please doctor answer me those 2 last question. Thanks you

[H. Hunter Handsfield, M.D.]

See my reply above.  I already told you there is no chance of a false positive in the situation you described.

This thread is over.