[Question #9505] Confused Source of Syphilis Infection Homosexual Male

32 months ago

I noticed a bump then ulcerated sore on my anus 15 Oct. 3 painful sores developed in the next weeks. 17 Nov I had a low grade fever and joint pain. Sores had discharge. 23 Nov I developed a torso rash & soon had blood tests. RPR Reactive 1:16, HIV Ab/Ag Negative. I went to Public Health and was examined/tested again. RPR Reactive 1:32, TPHA Reactive. I was diagnosed with Secondary Syphilis and treated with a single Penicillin injection.

I have a partner but I did have protected insertive anal sex and unprotected receptive & insertive oral sex with other anonymous males 31 Aug & 22 Sep (oral only). No contact with my anus occurred in either case. I’ve had other similar exposures in the months/years previous but the only anal contact was fingering at a massage 7 months ago.

I had unprotected insertive and receptive oral and anal sex with my partner numerous times Jul-Oct. Public Health pointed to my partner as the likely source of infection. I told him and he tested for Syphilis. I don’t know what specific tests but he said results were non-reactive, 6 weeks after last contact with me.

Questions: (1) I understand the chancre occurs at the site of inoculation. Could it appear on my anus from the other sexual contacts described? (2) Is this clearly primary/secondary or should I be concerned about latent syphilis? (3) This started 10 days after my 1^st Monkey Pox Vax. Is there any relation? (4) My partner will test again at 90 days post-contact. Will this be enough?

Edward W. Hook M.D.

32 months ago

Welcome to our Forum and thanks for your questions. I'll be glad to comment. Condoms remain superb methods for prevention of STIs which cause mucosal infection such as gonorrhea, chlamydia and HIV but may be somewhat less protective for STIs which cause lesions as, depending on where the lesions are located, they may not cover the lesions. Further, with respect to syphilis, as the infection moves towards the secondary stage, the infection is systemic and infections lesions may occur at sites other than the primary site of inoculation and serve as sources for transmission. For this reason, careful evaluation of sexual contacts from the 90 days prior to infection and, in some instances, preventative therapy is warranted. With this preliminary information, I'll address your specific questions:

(1) I understand the chancre occurs at the site of inoculation. Could it appear on my anus from the other sexual contacts described?

As indicated above, your syphilis may have occurred as a result of one of the contacts described above

(2) Is this clearly primary/secondary or should I be concerned about latent syphilis?

Latent syphilis is the stage of syphilis in which clinically detected lesions, including rash or ulcerated lesions are not detected. Early latent syphilis is the stage of infection occurring within the year after the appearance of lesions and is treated tin the same way as primary and secondary syphilis. You had lesions and so you had early syphilis which is the term used to describe primary (lesions at the site of inoculation), secondary (with systemic lesions and rash).

(3) This started 10 days after my 1st Monkey Pox Vax. Is there any relation?

Congratulations on getting the MP vaccine - I'm pleased to hear you got it. It is recommended and a good idea. MP may travel in the same groups who are at risk for syphilis but at the moment (we are still learning) there is no other relationship between MP or the MP vaccine and syphilis other than the tendency to occur in groups with similar risks.

(4) My partner will test again at 90 days post-contact. Will this be enough?

Presuming that you and your partner have regularly had contact, most experts would recommend preventative penicillin therapy, followed by blood tests out to 30 days to validate its effectiveness.

I hope this information is helpful. If there are further questions or parts of my response are unclear, please use your up to two follow-ups for clarification. EWH

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32 months ago

Thanks Dr. I understand and accept responsibility.

My partner is in a conservative country on another continent. We see each other 5 or 6 times/year for a few weeks at a time. I’m certain he did not tell his provider about homosexual contact or exposure to a confirmed syphilis case, but rather only requested syphilis screening. He will not be offered treatment without admitting to these facts or a reactive test.

Follow-ups (1) My partner was exposed to the anal bump 1 time before it ulcerated. We have not had any contact since mid-Oct. He was tested in early Dec. How reliable is his 6 week test? If his tests remain non-reactive at >90 days can he be considered conclusively uninfected? And are we then safe to resume unprotected sex? (2) Was I adequately treated? Do I need anything beyond follow-up blood tests (3, 6 & 12 months) to confirm lower RPR titers? (3) My HIV Duo test was 37 days post-contact with my partner, my only unprotected anal exposure. Exposures since then were unprotected insertive/receptive oral sex and 1 instance of protected insertive anal sex. Is there any need to re-test for a conclusive result? (BTW, oral, rectal and urethral swabs at Public Health were all negative). (4) All said I will attempt to change my behaviors but I know indiscretions are still likely to occur. How risky is unprotected oral sex (insertative/receptive) really? Was this a “one-off”? Or likely to reoccur unless I abstain from all contacts?

Edward W. Hook M.D.

32 months ago

If your partner cannot acknowledge his contact to get preventative therapy but has access to antibiotics, and I understand the timeline, I would suggest he take treatment preventatively. He could take doxycycline, an antibiotic taken for many other sorts of infections, 100 mg twice daily for 14 days and be confident that infection, if incubating, was prevented.

Regarding your follow-up questions:

(1) My partner was exposed to the anal bump 1 time before it ulcerated. We have not had any contact since mid-Oct. He was tested in early Dec. How reliable is his 6 week test? If his tests remain non-reactive at >90 days can he be considered conclusively uninfected? And are we then safe to resume unprotected sex?

His six week test is good but not great evidence that he has not been infected. Even so, out of an abundance of caution, I would suggest the preventative therapy I mention above. A 90 day negative test would prove that he was not infected.

(2) Was I adequately treated? Do I need anything beyond follow-up blood tests (3, 6 & 12 months) to confirm lower RPR titers?

Yes, I presume you were treated with 2.4 million units of benzathine penicillin (there are several different forms of penicillin, benzathine is the formulation recommended for syphilis). This is appropriate therapy for the stage of syphilis you had. At this point, all is needed is follow-up RPR tests.

(3) My HIV Duo test was 37 days post-contact with my partner, my only unprotected anal exposure. Exposures since then were unprotected insertive/receptive oral sex and 1 instance of protected insertive anal sex. Is there any need to re-test for a conclusive result? (BTW, oral, rectal and urethral swabs at Public Health were all negative).

Your 5 week test result is strong evidence that you were not infected with HIV and is about 99% conclusive. Fully conclusive testing would be to test any time more than 6 weeks following exposure. There is no known risk for HIV from receipt of oral sex. The risk of acquiring HIV from unprotected performance of oral sex is less than 1 infection per 10,000 exposures, if your partner was infected and not on treatment. Similarly, the risk for infection from unprotected insertive anal sex with an untreated infected partner is about 1 infection per 1000 exposures, on average. As you continue to have sex with partners of unknown HIV status, please test periodically or consider talking with a health care provider about taking HIV pre-exposure prophylaxis (PrEP). It is highly effective and well tolerated

(4) All said I will attempt to change my behaviors but I know indiscretions are still likely to occur. How risky is unprotected oral sex (insertative/receptive) really? Was this a “one-off”? Or likely to reoccur unless I abstain from all contacts?

See my comments above. No further contact, no further risk. OTOH, continued contact does have associated risks. Consider discussing PrEP with someone at a sexual health clinic. EWH

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31 months ago

Doctor, thanks for your responses. Yes. I was treated with Bicillin 2.4MU IM 1 dose. I’ve been reading this carefully and trying to understand. I know this is my final opportunity, so I want to be sure my understanding is clear.

(1) So are you saying I was likely infected through the unprotected insertive and receptive oral or protected insertive anal exposures I described and the lesions I had on my anus were not the primary infection but rather part of the secondary? That would mean I missed the primary chancre on my penis or in my mouth several months ago?

(2) I really want to know how I got syphilis so I can ensure it doesn’t happen again. I really thought I was being pretty safe in this regard. I understand receipt of anal fingering at the massage is out of the question as the source, but can you please be more clear about the risks of syphilis from oral sex among MSM?

(3) I’ve read on this site, MedHelp and others that 6 week syphilis testing is highly accurate, so can I understand my partner’s result is unlikely to change at 90 days since we haven’t had any contact since Oct?

(4) Finally, how long does it take for lesions to heal? The rash is gone but I still have 1 perianal sore. It is still slightly painful, but no longer an aggravated red color, not bleeding and no discharge.

Thanks Doctor for your availability and expertise but especially for making this a non-judgmental space. This forum is very valuable to many of us seeking knowledge and understanding to stay safe.

Edward W. Hook M.D.

31 months ago

Thanks for your thanks. I'm glad my comments have proved helpful. Addressing your follow-ups:

Once can never be sure. The is no doubt that you had early syphilis. As to where the initial lesion, my sense is that the earliest lesions you noted were in mid-October. Whether the initial lesions were your primary chancre(s) or not is not entirely clear but, given the time line in which there was an anal lesion noted in mid-October and then weeks later your rash appeared, this would seem to be the most likely scenario.

I appreciate your desire to avoid repeat infection but of course, cannot guarantee it. In fact about one in four persons who are diagnosed with syphilis have had it again. Since among STIs syphilis is relatively uncommon, this suggests that persons who acquire syphilis tend to circulate in groups who are at increased risk. I am not going to tell you to change your interactions with others. The things you are doing, using condoms with casual partners, getting checked periodically are the best way to reduce risk but cannot eliminate it.

Correct. The key word here however is UNLIKELY. It is not a certainty which is the reason I suggested he may wish to seek preventative antibiotics.

Most typically the lesions of syphilis resolve within a week or two after treatment. If now more than a month after treatment you have a lingering lesion, I would suggest that you have a trained health care provider look at it. Persons who get on STI may get others and there are other processes which may cause persistent anal lesions. If your rash and ther lesions have resolved following treatment, I would doubt that the persisting lesion is syphilis and would encourage looking for other causes.

I hope the information I have provided has been helpful. I wish you the best. EWH

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