[Question #1931] Risk and PEP (Part 2)

92 months ago

Dear Dr. Handsfield,

I am following up on my earlier questions due to some developments. Since my last post, my discharge became worse and was clear, thin, and sticky, I visited a urologist and he asked me to take a urine PCR test for gonorrhea and chlamydia. After that he gave me 1.5 grams of zithro and 600 mg cefixime which I took last Monday night. I just got the results today and gonorrhea is negative but they said they need to retest chlamydia and will not be able to give me the results for a week (never heard of this test taking so long).

Now, from your earlier threads I understand chlamydia is impossible to get from oral sex and NGU is also very unlikely from oral sex, so I am assuming that the condom must have slipped off and I continued to have unprotected vaginal sex for a few minutes as that would be the only way for me to have chlamydia or NGU. This makes me more anxious for HIV.

I managed to track down the first csw and made her take an HIV duo and pcr and both were negative. So, my hope is that the unprotected sex happened with her and not the second csw (who I am very worried about as she suggested for me to use 2 condoms, and the person in charge of the brothel refused to let me take her for a medical even though I offered him a lot more money than the cost of the csw).

So given these new developments:

1. Looks like the 2 gm zithro I took a week before the incident may have been ineffective (is that even possible? – i.e. perhaps there was not enough zithro left in system after 1 week ).

2. I still have some symptoms (though much less) about 6 days post medication. Should I consider switching to doxy or take a test of cure first (and when)?

3. What are the statistical odds of chlamydia transmission from female to male for vaginal sex?

4. If the csw had chlamydia and HIV, would the chlamydia make her more infectious for HIV (i.e. would it increase my risk)? I have read that this is the case.

5. I am still continuing PEP as I feel that already 2 weeks are over so I may as well do everything possible to have a favourable outcome. Based on the new developments, would you still feel PEP was not warranted?

6. Based on the new developments, what would you estimate my risk of acquiring HIV to be (with and without PEP)?

7. Do you think doing a duo 2 weeks after PEP is over is worth it? I know guidelines say to wait until 3 months post exposure, but do you really think I can take a duo earlier than that with some confidence?

Thanks!

Edward W. Hook M.D.

92 months ago

Welcome back to the Forum. By chance I happened to pick up this most recent group of questions. I did read your interaction with Dr. Handsfield and agree with all that he has already said. While the chance that you acquired an STI from the encounter s you described is low, I also agree with your decision to re-test at this time. The discharge you describe sounds more typical of normal genital secretions than and STI. I would not have treated you unless your tests were positive however, if you had an STI, the treatment you have recently taken would be expected to cure gonorrhea, chlamydia, NGU and other possible STI causes of urethral discharge. I will now qaddress your specific questions:

1. Looks like the 2 gm zithro I took a week before the incident may have been ineffective (is that even possible? – i.e. perhaps there was not enough zithro left in system after 1 week ).

See above. This may not be an STI. sometimes following an encounter that persons feel worried about there is an increased tendency to notice nomal genital secretions which can vary in amount. If this were an STI, I would anticipate the medication you took to improve this and the fact that it has not further suggests that this is not an STI.

2. I still have some symptoms (though much less) about 6 days post medication. Should I consider switching to doxy or take a test of cure first (and when)?

See above. Further evaluation should include a test (preferably a gram stain of secretions obtained with a swab) of the discharge looking for white blood cells. If there are no white blood cells this is unlikely to be an STI. If I were going to treat this further (based on test results) I would use moxifloxacin for a7-10 days.

3. What are the statistical odds of chlamydia transmission from female to male for vaginal sex?

There are no firm data however estimates suggest that a male exposed to in infected sex partner has about a 20% (1 in 5) chance of getting an STI from a single episode on unprotected penile-vaginal sex.

4. If the csw had chlamydia and HIV, would the chlamydia make her more infectious for HIV (i.e. would it increase my risk)? I have read that this is the case.

You are getting into "what if" questions- try not to. Estimates are that like other STIs, the presence of chlamydia in an HIV infected person would increase the risk for HIV transmission by 2-3 fold.

As Dr. Handsfield indicated, PEP is a personal choice. Having started it, I see little reason for stopping it unless you are having bad side effects.

6. Based on the new developments, what would you estimate my risk of acquiring HIV to be (with and without PEP)?

Another "what if" question. Like Dr. Handsfield, I would not be worried about your risk for HIV. The fact that you have now proven that at least one of your CSW partners did not have HIV makes me still more confident that you did not get HIV from the exposures you have described.

I see no reason not to test 2 weeks after completion of PEP as I sense it might help your anxiety but I would not call your results strongly suggestive until testing 4 weeks after completion of PEP.

I hope these further comments are helpful. As you know, if any of this is unclear, feel free to follow-up. EWH

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91 months ago

Dear Dr. Hook,

I just got the chlamydia result back after a long delay and it was negative. So, I feel that it must have been NGU as I definitely did have a discharge and urethral discomfort which resolved approximately 7 days after I took the medication. And since NGU is spread by unprotected vaginal (not oral) sex, I can assume that at some point the condom did slip off and I had unprotected vaginal sex for a brief period of time.

I am also a little concerned as from day 15 and continuing till now (I am currently at 3 weeks now), I developed symptoms such as body pain (sometimes enough to wake me at night), diarrhea for a few days (and general changes in bowel movements), and swollen and painful right inguinal gland. At first I thought some of the pain and diarrhea could be from the PEP, but I never had it in the first two weeks, so unlikely a side effect from the medication would show up after 2 weeks.

So my questions are:

1. If we had to put a statistical number on it, would it be correct to say that the odds of unprotected vaginal sex would be 1:2000, which is doubled because I'm uncircumcised 1:1000, which would be tripled because I was exposed to NGU 1:333 (.30%)

2. Would it be correct to assume that PEP may reduce the odds by 75%? If so, odds now become 0.23%?

3. Do the symptoms I have seem to be ARS and if one had ARS during PEP, would it stand to reason that the symptoms would be muted since the volume of HIV would be less due to the PEP (and hence no fever or other symptoms)?

4. Since I did not have side effects from PEP for the first 2 weeks, would it be safe to assume that the symptoms I've been experiencing cannot be from the PEP because if it was, I would have had them from the beginning?

5. If it indeed was ARS, then how long after ARS started would a Duo test be accurate?

I hope everything is ok, but am getting worried now.

Thanks!

Edward W. Hook M.D.

91 months ago

I will address your follow-up questions momentarily. Before I do let me correct one misperception that you have. Non-chlamydia NGU can certainly follow receipt of unprotected oral sex. While chlamydia is almost never transmitted through oral sex, non-chlamydial NGU can follow. This problem is thought to occur when, during receipt of oral sex, bacteria from the mouth are introduced into the male urethra. It is questionable about how serious non-chlamydial NGU is or whether is can cause complications. in some clinics in the United Kingdom, partners of persons with non-chlamydia NGU are not treated.

Secondly, while you are convinced that your condom failed and that you have or had an STI, I am not. You have not had any tests which prove the presence of an STI and your thoughts that the condom failed can be debated.

Now on to your follow-up questions:

You are playing numbers games which are of little benefit. Your math is correct but this assumes that your partner had HIV which is quite unlikely and that your condom failed. The 1 in 333 estimate is statistically quite high- how much so id difficult to say.

2. Would it be correct to assume that PEP may reduce the odds by 75%? If so, odds now become 0.23%?

This is an overly conservative estimate of PEP efficacy which is probably closer to 90% or even more.

Your symptoms are not classical ARS and there are no data on whether ARS occurs when PEP fails or how the ARS would manifest itself it they did.

No, drug adverse effects do not need to start immediately when a medication is taken. There are many, many possible causes of your symptoms, particularly your GI side effects.

5. If it indeed was ARS, then how long after ARS started would a Duo test be accurate?

If a persons were experiencing the ARS a 4th generation HIV test would likely be positive at that time and certainly would be positive a few days after the onset of the ARS.

Let me know say what I have implied earlier. I think you are over reacting and that there is very, very little chance that you acquired HIV or, for that matter, any other STI from the exposures you have described. I hope my comments prove helpful to you. EWH

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91 months ago

Dear Dr. Hook,

Thank you for the information. I did a HIV Duo test on the 25th day after exposure (while still on PEP) to rule out ARS during the PEP. The result was non-reactive. So my last questions are:

1. You have indicated that testing with Duo is not definitive until 4 weeks after PEP completion. Would a negative test at 25 days be reassuring or does it not really mean much at this timeline stage?

2. Would a negative Duo at the 25th day (while still on PEP) mean that the symptoms were definitely not caused by HIV and definitely was not ARS? Or is it possible that PEP affects antigen/antibody such the Duo test is inaccurate (or not meaningful) if taken during PEP even if symptoms are present?

Thanks again for all your help! This will end my post.

Edward W. Hook M.D.

91 months ago

1. There would be little useful information for me from a 4th generation HIV test taken while on PEP. From my perspective the close to no risk nature of your exposure is more reassuring than a test result while taking PEP. I think you have gone overboard here.

2. Yes,, the ARS occurs because of the presence of high levels of HIV virus and antibodies. A negative 4th generation test is evidence that your symptoms were not due to the ARS.

This ends this thread. EWH

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