[Question #6806] Oral Exposure - Risk

12 months ago

Dear Drs

 

4 March: Received unprotected oral sex (5 min) from a female friend of mine who is a 25 year old journalist from the UK.

25 or 26 March: noticed small reddish patch/blotch towards the base of my penis head. Its not a perfect circle but like a small slightly misshapen patch. I am circumcised. No pain, no itching, or discomfort.

 

Worried about potential syphilis.

 

29 March: examined by my derma, was told its only a mild eczema-like skin irritation. Gave me Mometasone Furoate 0.1%, Miconazole Nitrate 2% to apply over 7 days.

31 March: it hasn’t changed in shape or look at all.

 

Questions:

 

(1)   Does this sound concerning? Am I overreacting? The timing is giving me anxiety – though it could be coincidence and unrelated.

(2)   I read on the British Medical Journal that primary syphilis starts as a macule then progresses to papule then to ulcer in around 7 days, and average time is 21 days; does 21 days refer to formation of a full chancre or only the macule?

(3)   If what I have is a macule, I assume from noticing it on 25 March it would have developed at least into a papule by now? It looks nothing like a papule or an ulcer and tomorrow will be 4 weeks since the exposure. How quickly does it progress usually?

(4)   Does this exposure warrant testing? If I decide to go tomorrow, on 1 April (exactly 4 weeks post-exposure) for a VDRL by RPR blood test, what % chance could this be accurate? 

(5)   Overall based on exposure, what % chance could I be infected (hard to know I’m sure but ballpark would be great!)

 

Thanks for your help in advance.

Edward W. Hook M.D.
Edward W. Hook M.D.
12 months ago

Welcome to our Forum and thanks for your question.  I'll be glad to comment.  My suspicion, as outlined below, is that this is coincidental and not syphilis or, for that matter, any other STI.  Oral transmission of syphilis is very, very rare and at the present time is far, far more common among men with other men as sex partners than among heterosexual men and women.  Further, when persons acquire syphilis, you are correct, the lesion starts as a macule (flat discoloration or redness) at the site of inoculation and then relatively quickly, over just a few days, first becomes firm and indurated and then goes on to form a painless ulceration.  While the time between your encounter and the appearance of this lesion is in the approximate time frame during which syphilis lesions can appear, given both the description you provide and the fact that you were examined by a trained clinician who felt that there were alternative diagnoses, I suspect this is more coincidence than anything else.  In answer to your specific questions:

1)   Does this sound concerning? Am I overreacting? The timing is giving me anxiety – though it could be coincidence and unrelated.

See comments above and below.  I suspect this is no and STI. 

(2)   I read on the British Medical Journal that primary syphilis starts as a macule then progresses to papule then to ulcer in around 7 days, and average time is 21 days; does 21 days refer to formation of a full chancre or only the macule?

Typically the transition from macule to ulceration takes only a few days.  The average time to appearance of the ulceration (chancre) is about 21 days. 


(3)   If what I have is a macule, I assume from noticing it on 25 March it would have developed at least into a papule by now? It looks nothing like a papule or an ulcer and tomorrow will be 4 weeks since the exposure. How quickly does it progress usually?

Correct.  Were this syphilis it would have ulcerated by now.  In addition, the topical medication you used would have accelerated the course, if anything.


(4)   Does this exposure warrant testing? If I decide to go tomorrow, on 1 April (exactly 4 weeks post-exposure) for a VDRL by RPR blood test, what % chance could this be accurate? 

The likelihood that this is syphilis is very, very low.  OTOH, blood tests for syphilis are easy to get,  highly reliable when a lesion has been present for more than a few days, and could relieve your anxiety.  I personally do not feel that testing is needed from a medical perspective but have no objection if it might be helpful to you. 


(5)   Overall based on exposure, what % chance could I be infected (hard to know I’m sure but ballpark would be great!)

Less than 15.  Probably far less.


I hope that these comments are helpful.  Should there be additional questions, please don't hesitate to use your up to two additional follow-up questions.  EWH


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12 months ago
Hi Dr. Hook

So at the 4-week mark I went to the lab and did full bloods and urine PCR and all came back negative, thankfully.

That patch is still there but at least I know now that, as you said yourself, it is unrelated to any STI.

Thank you as always for your time and valuable guidance. Much appreciated.

Best Wishes
Edward W. Hook M.D.
Edward W. Hook M.D.
12 months ago
Thak you for the follow-up.  It is much appreciated.  Pleased to hear of your negative tests.  Take care.  EWH
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