HIV test while on PEP

[hotwheels]

I am toward the end of my PEP treatment after broken condom incident where I was on the receiving side of anal contact. To my surprise my doctor ordered HIV tests (RNA PCR and AB) yesterday (25th day of my PEP and 25th day from exposure) saying that if I tested negative than 99% PEP worked or I was not infected. But I've read on the next that testing should be done 13 weeks after PEP finishes because there are many false negative results during PEP. Should I trust my doctor and if I test negative now have unprotected sex with my girlfriend? And if I test positive I guess PEP didn't work and no chance it will wrok in the last couple of days of treatment?

[RapidRod]

You need to test 3 months post your last dose of nPEP to obtain your conclusive test result.

[jkinatl2]

Yeah, I agree with RapidRod. The purpose of PEP is the same as the purpose of HIV medication, which is to suppress viral reproduction. That's because PEP consists OF HIV medication, much the same as that given to those who are positive.

It does concern me that your doctor is not aware of this. Certainly any negative test is a good thing, but ONLY a test at three months AFTER PEP is definitive - though a test at six weeks is almost a sure thing.

[Ann]

Wheels,

Here's how PEP works:

PEP works exactly the same as it does in a confirmed positive person. It stops the virus replicating during various times in its life-cycle. When a person has very recently been infected and PEP is initiated within three days (72 hours), the virus can be stopped in its tracks, before it gains access to the various reservoirs in the body where it can hide from the meds. The fact that hiv hides in reservoirs is one of the reasons why a cure for hiv is so elusive.

The theory is that if hiv gets into the reservoirs before PEP is initiated, once PEP is stopped it can come out of hiding and start replicating in the blood again, because the meds are no longer in the blood. This means the process of antibody production starts within two to three weeks, when there is enough virus in the blood to trigger this response from the body's immune system. That's why we count the window period from the last day of PEP.

The biggest question mark over this process is that we don't know for sure whether or not hiv that may be hiding in the body's reservoirs can trigger antibody production. I'm not sure if we'll ever be able to answer this question.

As Jonathan mentioned, any doctor who gives a patient who is actively taking PEP a viral load test (aka VL; aka RNA PCR) doesn't have a clue as to how PEP works. Your test result will come back undetectable (negative) but that is not going to tell you whether or not you've been infected.

The whole purpose of taking hiv meds is to suppress the virus and achieve an undetectable VL and quite frankly, it's just stupid to give a VL test to someone who is still taking PEP. An undetectable result is pretty much a foregone conclusion, because a VL test will not detect hiv that may be hiding in reservoirs.

Regardless of what result you get from the PCR test, you will still have to confirm that result with antibody testing at the appropriate time.

You should not be having unprotected intercourse with your girlfriend unless you have BOTH tested hiv negative at the appropriate time together. To do otherwise is irresponsible on both your parts. Seriously.

Here's what you need to know in order to avoid hiv infection:

You need to be using condoms for anal or vaginal intercourse, every time, no exceptions until such time as you are in a securely monogamous relationship where you have both tested for ALL sexually transmitted infections together.

To agree to have unprotected intercourse is to consent to the possibility of being infected with an STI. Sex without a condom lasts only a matter of minutes, but hiv is forever.

Have a look through the condom and lube links in my signature line so you can use condoms with confidence.

Anyone who is sexually active should be having a full sexual health care check-up, including but not limited to hiv testing, at least once a year and more often if unprotected intercourse occurs.

If you aren't already having regular, routine check-ups, now is the time to start. As long as you make sure condoms are being used for intercourse, you can fully expect your routine hiv tests to return with negative results.

Don't forget to always get checked for all the other sexually transmitted infections as well, because they are MUCH easier to transmit than hiv. Some of the other STIs can be present with no obvious symptoms, so the only way to know for sure is to test.

Use condoms for anal or vaginal intercourse, correctly and consistently, and you will avoid hiv infection. It really is that simple!

Ann

[hotwheels]

Thanks for the replies, especially to Ann for the very detialed response.

That's exactly what I gathered from the net too,  indeed it seems like my doctor is not quite good as far as it comes to PEP. Quite strange, as he is doctor in a gay/lesbian clinic deicated to HIV and STD in Chicago.
Anyways, I will still consider negative result in the tests I already had as very good thing, and will test at 6 weeks and 3 months after PEP finishes and not have unprotected sex meanwhile with my gf.

In fact there are other couple of strange things in my PEP treatment. The doctor told me to take PEP for 1 month, not 28 days. Also what happened is that I had some stockpile of PEP with me (Truvada and Combivir) and so immediately after the accident I started on both. Then 5 days later I went to see the doctor who switched me on Truvada, Ryataz, and Norvir and told me to take them for 30 days from this date on. Seems too much, doesn't it? And I've got RNA PCR test at that point which came out negative (in fact, it didn't say undetectale, but said less than 20 copies/mg and the doc said it means undetectable). Three weeks later I got the second test and the doc said this is to close the window period and if it is negative than 99% PEP worked.
I am also thinking - for someone that has risky behaviour like I do wouldn't it make sense to take Truvada regularly as prophylaxis?

[Ann]

Wheels,

Sorry for the late response - I somehow missed your last post yesterday.

While the med combo the doctor switched you to is not one normally recommended for PEP, it is an effective first-line treatment for established hiv infection and it will work just as well for PEP. I would imagine that he told you to take it for 30 days because the meds come in bottles of 30 pills - he probably figured you may as well take the whole bottle(s) rather than have a few go to waste. It's not a big deal.

If I were you, I'd question the doctor next time (just because I'd want to get to the bottom of his reasoning - I'm naturally curious) about why he thinks PCR testing is appropriate while a patient is on PEP. It makes no sense to me and that's why I'd want his answer. PCR testing is expensive and I can't imagine why he'd want to add to the monetary health care burden when the PCR test results are for all intents and purposes meaningless in this situation. Maybe he gets kick-backs from the lab for sending business their way; who knows. I can't see insurance companies liking what he's doing - and for patients paying for these unnecessary test out-of-pocket, well, that's just a nightmare.

Truvada used as PrEP (prophylaxis) was approved by the FDA earlier this year. However, I don't know if insurance companies will cover it, so you may have to pay out-of-pocket for it.

You also need to understand that you'd need regular blood test to make sure you're not having side effects that may not be obvious to you, such as kidney dysfunction associated with the tenofovir portion of Truvada. You'd want to do blood draws to check on your kidney function, liver function and CBC at least quarterly for the first year or so, and then once or twice a year afterwards, because the ill-effects don't always happen right away.

Don't get me wrong, side-effects don't happen to everyone, but, for example in the case of kidney damage, if you aren't being regularly monitored you may not know there's a problem until it's a BIG problem.

So you see, it's not as simple as merely taking a pill a day. You also have to understand that it IS a pill a day, not just say, over the weekend when you're out having fun. It's a pill every single day, and an expensive pill at that. And it doesn't mean that you don't need to keep using condoms either. Truvada as PrEP is most effective as a back-up to condoms; it's not a replacement. You'll have to decide for yourself, in conjunction with consulting a trusted doctor, whether or not Truvada is for you.

BTW, just as a matter of interest, I was at my hiv clinic this past Tuesday and I was asked to take part in a study looking at why some people have kidney problems associated with tenofovir (I take Truvada). They're going to look at various components of my bloodwork, including DNA. They want to see if there is a marker that some people have that others don't and if there's any correlation with the kidney dysfunction.

Similar studies on another hiv drug called abacavir identified a gene marker that was present in people who were having adverse, life-threatening reactions to this med, so now we can test people for this gene before putting them on abacavir. Great stuff, and I hope they identify a similar marker for kidney dysfunction associated with tenofovir. Being able to avoid the kidney problem would be beneficial to many people. 

Ann

[hotwheels]

Thank you, Ann, for detailed and helpful answer.

I am not sure who pays for the PCR tests but it is not me. I just pay $20 copay for the office visit and I don't have insurance.  I think it is gay/lesbian center which is subsidized by some private funding too.

What do you think is the best combination for PEP treatment? Previously I was prescribed Combivir+Truvada in sex clinic in Amsterdam, although I didn't use it back then, I just wanted to have stockpile of the medications in case of need. And I am glad I did, because now when accident actually happened I was able to start one hour after exposure. And my doctor now in the US said that Truvada+Combivir is unusual combination as they work in the same way. So it seems like everyone has different opinion what is the best combo.

Interestingly, for the whole 4 weeks now I've been taking PEP, I haven't had any side effects - no diarrhea, no vomitting, nothing. Still, last time the doctor also ordered full blood count to check the liver function.

Thinking more about PxEP, maybe is not that good idea after all. Maybe is better to just have stockpile of PEP meds and if condom breaks to do PEP. After all, condoms do not break that often. In my whole sexual life I've had three broken condoms and two of them as being top with women. So this is my first really dangerous accident.