Hi Doctors

I had a question answered by Dr Hook recently. Just to recap I had unprotected oral sex (giving and receieving) with a female CSW in Manchester England on 29th of December. I tested negative for Syphilis 32 days and 46 days after the encounter. The first test was a rapid test performed by the doctor, the second test was an igg/igm by eia lab based test.

Dr Hook said there was no medical reason to retest but the 9-90 day incubation period is causing me a degree of anxiety so I'm considering testing again at the 12 week mark.

My questions are:

1: How accurate is an IGG/IGM test at 46 days?

2: What is the science behind 6 weeks conclusive syphilis test when the incubation period is 9-90 days?

3: I currently take 10mg of citalopram per day to help with my anxiety, would this medication affect a future syphilis test at all?

4: If I test again at 12 weeks would you expect my result to remain negative?

5: Assuming the test remains negative at 12 weeks can I finally draw a line under this issue?

My main concern is that my wife is pregnant and I cant take any risk with her health at all. No matter how statistically unlikely it may be.

Thanks in advance for your help.

James:

I'm sorry you continue to worry about the exposure you described in your original post.  Before I address your questions,, let me provide you with some data.  Syphilis is a very rare disease, even among commercial sex workers.  At the present time in North American and in the UK, over 60 % of syphilis occurs in less than 10% of the population- men who have sex with other men.  The disease is rare among commercial sex workers and among the same proportion of people who have syphilis, the infection is almost never transmitted by oral sex or kissing.  Thus your risks of infection, even before testing are tiny.  Further, syphilis test recommendations going out to 90 days are, as I mentioned to you, overly conservative and intended to not missed possible infections but from a practical perspective, should be believed, particularly if no lesion has appeared, at 30 days after exposure. 

My guess is that your anxiety is more a manifestation of your own guilt and anxiety than anything else.  Further testing will not address this. 

With that, let's deal with your questions:

1: How accurate is an IGG/IGM test at 46 days?

There are not specific data on this test at 4 days but such tests would be expected to detect well over 95% and probably closer to 100% of infections at 45 days.

2: What is the science behind 6 weeks conclusive syphilis test when the incubation period is 9-90 days?

A better question is what is the science on incubation periods of 9-90 days.  such estimates have been handed down for decades, before the time of modern science.  As I think I mentioned, syphilitic lesions typically appear less than 21 days after exposure and blood tests become positive at about the same time.  The 90 day upper limit has little objective, scientifically proven basis.

3: I currently take 10mg of citalopram per day to help with my anxiety, would this medication affect a future syphilis test at all?

No, your citalopram would not effect your syphilis test in any way.

4: If I test again at 12 weeks would you expect my result to remain negative?

I am quite confident that further testing, now, at 12 weeks or at 12 months will show that you were not infected with syphilis through the exposure you describe. 

5: Assuming the test remains negative at 12 weeks can I finally draw a line under this issue?

Sort of a silly question, isn't it?  I told you I was confident of your results at 46 days.  I'm equally confident about a 12 week results.

I hope my replies help you.  EWH

Dr Hook

Thank you once again for your response and I am sorry to have bothered you with this again. I just cant shake it. I understand the facts that you are putting in front of me and they make sense, but regardless I seem fixated on the miniscule % that I could be infected.

I do have a few more questions:

1: My biggest fear is that I've missed a chancre inside my mouth and that I have spread that bacteria to my wife and unborn child via kissing. Does this sound at all possible? my wife has developed faint red pimples around her mouth and lips.

2: I have read through countless threads about syphilis over the last 2.5 months, Now, Dr Handsfield seems absolutely adamant that 6 weeks is 100% conclusive for syphilis, whereas, you have said that the accuracy could be as low as 95%. It is these tiny differences which is causing me to feel like I need further testing at 12 weeks. Can you explain these discrepancies please?

3: I have read on some other sites that IGM antibodies become detectable after 2 weeks and IGG at 4-5 weeks. Is that true and if it is why would my test at 46 days not be considered 100%?

4: Is there anything that could potentially cause a delay in these antibodies showing up in a blood test at 6 weeks?

5: Have you ever seen a negative result after 6 weeks that was later proved to be positive?

Hi Dr Hook

Thanks so much for your last response. I am feeling a little better today. Perhaps the Citalapram is kicking in and giving me more rationality?

I do appreciate your advise and I will try to take it on this time. Apologies if I have been a pain in the ass. You'll be pleased to know I have not been googling syphilis related issues today.

Final question, just so I can get everything straight in my head, you would recommend no further testing and that further testing would simply be a waste of time and energy given my exposure and 2 negative tests?

Correct.  Emphatically, your tests prove that your did not get syphilis from your misstep.  Further testing would be a waste of time and money. 

As you know, this is my third and therefore final reply to your questions.  This thread will be closed in a few hours.  I urge you to move forward without concern.  Enjoy your forthcoming fatherhood.  EWH.