Hello doctors,

I recently received an std panel as I have been worrying about a lymph node that has been around my neck after a sexual encounter I had almost 2 years ago. All the results came back non reactive. I was relieved until I read that the RPR test can be false negative after some time when syphilis has been untreated. I am now worried that the RPR missed the syphilis infection and I have undetected syphilis because it has been 2 years since the exposure. I have also read that if my lymph node was in fact due to syphilis the test would have been positive even if its been 2 years? can you clear this up for me? I just want to put this to rest already. Tired of getting tested.

Lymph node swelling due to syphilis occurs in two ways.  Following the appearance of a lesion of primary syphilis (the earliest stage) local, regional lymph node swelling may occur.  Thus most early lymph node swelling due to primary syphilis occurs in the inguinal region.  Later, several months after acquistion of syphilis, more generalized lymph node swelling can occur in many regions of the body.  Both these forms of lymph node swelling tend to go away as time after infection passes.  Isolated lymph node swelling in the neck due to syphilis would be quite unusual.  Further, if your swollen lymph node were due to syphilis, your RPR test would certainly be positive.

Lymph node swelling is a non-specific inflammatory reaction.  Lymph node swelling in the neck can be due to dental or gum disease or other problems around the head  and neck.  Most people have lymph nodes which can be felt if one looks for them, particularly if the person looking is a trained clinician.

If you had acquired syphilis 2 years ago and had not been treated, your RPR would certainly be positive at this time.

Based on what you say above, it is highly unlikely (i.e. virtually a certainty) that you did not acquire syphilis from the encounter you mention.  EWH

Thank you for your quick response doctor. So just to be clear:

1. Lymph node swelling for 2 years does not suggest syphilis as a lymph node from an std would not last that long so its probably something non std related?

2. If the lymph node ive had was due to syphilis the rpr and other std tests i received would have been positive?

3. When you say virtually a certainty that I did not acquire syphilis that means I do not need further testing correct?

4. I did not fast for the rpr test. Is fasting or any special preparation needed for rpr or other std tests?

5. Could vaping or smoking cigarettes cause a false negative?

1. Correct.  

2.  Correct 

3.  Correct 

4.  Best thing makes no difference in RPR test results.

5.  Absolutely not.

EWH

So regardless of symptoms or if a person has no symptoms an RPR does not go negative after a course of 2 years? For a RPR to go negative with untreated syphilis a person would need to have untreated syphilis for decades and not a couple of years correct? and even that is uncommon? sorry ive been googling too much

Please accept that you did not acquire syphilis.  It's time to move forward.

This completes this thread. EWH