Unprotected Oral, Syphilis

[StevenR0]

Hi Doctor,

I had unprotected insertive oral sex with a CSW about 13 days ago. She gave unprotected oral sex for about a minute, until I got an erection and then I asked her to put a condom on which I took it off minutes later to *** into her mouth.
After 7 days since the exposure, I saw a pimple like an my scrotum, near the base of my penis. I thought it was a pimple because I shaved that area a few hours before I've had the exposure. I squezed that pimple and some watery liquid came out and I also peeled the skin. I also squezed a few time the next two days. It looked like the pictures of the syphilis chancres I saw on the internet, round, with only 3-4 mm in diameter, but I thought it was only a sore from peeling the skin.
I exposed the sore to air and after 1-2 hours the area where the skin was peeled off got harder like thin crust. In the morning, after a night when the sore was not exposed to air, the crust witch was now white-yellow, came off and again the sore looked like a chancre. Over the next days I continued to expose the sore to air cause I felt it was healing because the crust it was forming on the peeled skin. Now it looks almost healed, but it still has the vulcano crater aspect.
For the last three days I took amoxicilline (875 mg) twice a day.

1. Have you ever heard of syphilis chancre developing as soon as 7 days?
2. If it is indeed a chancre, why did it healed to quickly? Is it because of the amoxiciline I took?
3. I'm aware that oral sex is very low(no) risk for HIV, but if the CSW had a syphilis chancre in her mouth, would make make the risk higher? If I indeed got syphilis from this encounter, should I consider a HIV test too?

Thank you!

[Edward W Hook, MD]

Welcome to our Forum.  I have reviewed the information you have received on the STD Community site an agree with the information you have been provided.  Syphilis is a rare STD and it is hardly ever transmitted through oral sex.  Furthermore 7 days is a bit early for a syphilis lesion to appear.  I suspect that the sore an crusting you note is just part of the healing process from the irritation you created when you squeezed the lesion.  It is typical for healing lesions to heal in the way you describe.

When people develop syphilis, they develop a positive blood test within just a few days after the sore appears.  Thus, if your lesion was syphilis, now that nearly a week has passed since it appeared, your blood test would be positive.  For your own peace of mind, I suggest that you get a syphilis blood test.  I am confident that it will be negative and when it is, I urge you to stop worrying about syphilis and move forward.

The sore, whatever it may have been due to, does not change the fact that receipt of oral sex does not put you at risk for HIV.

Take care. EWH

[Edward W Hook, MD]

Although syphilis is slightly more common in EAstern Europe, it remains uncommon.  A syphilitic lesion would not form the crust that you describe but this would be typical of  bacterial contamination of a wound resulting from squeezing an manipulation of the sort you describe.  

The amoxicillin might cure a bacterial wound infection.  Your syphilis test result (which will be negative) is still reliable. EWH

[StevenR0]

Thank you for your answer Dr. Hook.

I live in an Eastern European country, so the rate of syphilis myght be higher than in the US. Also, the sore I have does look like a chancre(ulcer) and it's soft in the morning, after hours of beeing coverd, but then again, when exposed to air gets harder and seems like a crust is forming. It has a hair growing from the middle of it.
I will get a test done sometime this week.
The fact that I took amoxicilline makes any diffrence when it comes to test?
I know 7 days is soon for a chancre to develop, the period being 10-90 days, but have you met any patient with a chancher after 7 days of the exposure?

Thank you!