Skin blisters/sores on buttocks and in mouth after unprotected sex

[smileboy]

Hi, i'm a homosexual and received unprotected anal sex about 5 weeks ago now. It was a one night stand. Prior to that i had been in a relationship of 3 years (im 22 by the way) to the same guy who i knew was HIV NEGATIVE. About 2 weeks after i had unprotected sex with the guy i developed a red rash around my anus which spread and became blistery, itchy and sore. I went to the doctor and told him my sexual history, however i told him that i had PROTECTED sex as i didnt really feel uncomfortable with him. he said it looked like impetigo an gave me a weeks antibiotics an told me if the symptoms persisted that i should go an have an STD screen. The antibiotics seemed to work and the irritation was clearing up. then the day after my antibiotics finished i got 3 more large blistery sores of the same variety on my right buttock and also developed something similar looking inside my mouth (gum). i went back to a different doctor, she said it did not look like anything sexual and it looked like a superficial skin infection and prescribed me some canesten cream with steroids and antibiotics in. i used the cream as instructed but the problem got worse an I developed other blister/sores on my other buttock and also my waist line. what is my risk of contracting HIV??

[H. Hunter Handsfield, M.D.]

It sounds possible that you have herpes, which could easily be mistaken for anal impetigo, especially since you mislead your doc into thinking you weren't at risk for STD.  The buttock lesions sound like they could be due to an early recurrence of herpes.  However, it would be unusual for lesions to also occur elsewhere, such as around the waist.  So on balance, you may or may not have herpes--I cannot tell, and of course cannot make any diagnosis from a distance.  You should return to your doctor (or find a different one) for evaluation for herpes.  If your buttock lesions heal before you see someone, you can wait and see if they recur, then seek care immediately when the sores are fresh (within 1-2 days); or you can have blood testing to see if you are infected with HSV-2 (or HSV-1).

The risk of acquiring HIV is low for any particular sexual episode, and of course it is zero if your partner was telling the truth and does not have HIV.  However, receptive anal sex is the single riskiest sexual practice there is; and simultaneous exposure to HIV and HSV-2 is a very high risk for HIV infection.  In other words, your actual risk depends mostly on whether or not your partner doesn't have HIV.  Since there is a chance he was in a window period, there still is at least some risk.

I suggest you contact your partner to discuss the herpes possibility, as well as your HIV concerns; he might decide to get retested and perhaps evaluated for herpes.  If there is any doubt about any of this, you should be HIV tested now and, assuming the result is negative, 3 months after the sexual exposure.

Good luck--  HHH, MD