False Positive or False Negative?

I apologise, about a month ago I posted a question about my positive chlmaydia pap smear test. I do however have a few more questions.

So, as a quick recap: a month ago my doctor informed me I tested positive for chlamydia. I have never been with any other man but my boyfriend, so I assumed he cheated on me. I told him to go get tested, and we both received medication. A week later, he received his results and they were negative. Me, being very naive and uninformed at the time, assumed this meant I had a false positive. We stopped using condoms about 2 years ago, and so I've basically shot down the possibility that he got treated for the chlamydia behind my back. More than likely he would have caught the chlamydia back and tested positive.

Anyhoo, so the doctor told me not to have sex with anyone for 7 days after taking the medication. We found out his negative test on the 6th day and had unprotected sex (I know, quite foolish). However, because of this, I decided to ask him to get re-tested. I'm hoping that if he lucked out and got a false-negative that this second test will pick up on that since we hadn't waited the full 6 days before having sex. That would be possible, right? Assuming that the infection hadn't cleared by that time?

[Clairebert]

correction: *hadn't waited the full 7 days

[Vance2335]

I'm not really sure what you are looking for. Any test by him if positive will tell you nothing.

[Clairebert]

Well, I thought because we hadn't waited the full 7 days before having unprotected sex that if he really had a false negative and he really did give me chlamydia, that this second test would pick up on that?

Also, what do you mean any test by him, if positive, will tell me nothing. I think it would tell me something, wouldn't it? It would mean his first test was a false negative?

[Vance2335]

False negative is very rare. And if he does retest since you didn't wait the 7 days there is a small chance that you could have given it back to him. So if he tests positive then it will not tell you anything about it.

[Clairebert]

I guess what I mean is that, it would prove to me that my test was a false-positive. Sorry, I realise now that I didn't give enough background info. He denies cheating on me quite adamantly, and because of his negative test result I thought that meant he was telling the truth. It's not until after talking to my doctor, who said that it's more likely he got a false-negative, that I decided to ask him to retest. If he did cheat on me, I don't want to be with him. I'm hoping this second test will resolve the issue somewhat, as if he tests negative it could quite potentially mean I tested false-positive. If he does test positive, then I know that he must have had a false-negative during his first test, and so I'll break up with him.

[Clairebert]

Also, as additional information. I have had a pap smear test back in 2009, and I was didn't test positive for chlamydia. It is only in my most recent test, September 2010, that I tested positive for chlamydia.  

[Vance2335]

False positive is a lot more likely then a false negative.

[Clairebert]

From speaking with my doctor, she said it is more likely that he got a false-negative, as he had a urine test which are less accurate than the cervical exam I had.

This is why I asked him to get re-tested, if he tests positive this time,.it means he cheated on me and he lucked out and had a false-negative test and didn't say so. If he tests negative, than I will have to consider that I may have had a false-positive result... though very unlikely, it is possible. I guess there'll never a sure way of knowing? I guess I wanted to post this thread to see if other people have gone through something similar...

[mandapanda1234]

Hello. I need help with this situation as well. Last year I had tested negative. I have been with my boyfriend for almost 4 years and I have been faithful, and not cheated. After i went to the dr and got pap and it came back that I had chylmedia i was shocked, and imediately i confronted him. he said that he had cheated on me about three weeks after I had my last years pap test. So i told him he needed to go be tested and treated, He waited about a week and then went to his reg dr office. they did a swap test or whatever I assume or so he says and his test came back negative. I do not understand this. I also spoke with the girl that he cheated on me with, and she also had tested positive for chylmedia. I am not getting anything resloved here, except fingers are being pointed at me as if i have been cheating. His dr says that his test is correct, my dr says it is possible that i could have had a false positive. I didnt have symptoms. I know that I did not cheat, so how did i end up with positive pap chylmedia results and we have been sleeping together for 9 months after he was exposed and his test is negative?????? this is really putting a strain on our relationship, and his mom seems think that i am the cheater in the relationship. it is hurtful in so many ways

[Vance2335]

You said you had sex before the 7 days so this could have reinfected/infected him. So even if he tests positive it will not say he had a false negative. And again a false positive is a lot more likely then a false negative.

[mandapanda1234]

he has not been treated, and no we have not had sex at all during my treatment.

[Vance2335]

I was addressing Claire. You have started your own thread and should continue all questions on that thread.

[Clairebert]

Hey Vance,

I don't think I'm quite understanding what you're trying to say. Can you explain WHY you think a false-negative from a urine test is less likely to happen than a false-positive cervical exam? The two doctors I have spoken say otherwise, that cervical exam are more accurate than urine tests.
Secondly, yes...it would say something if he tested positive because it would mean that I did have chlamydia in the first place. Because he had a negative test, I assumed he hadn't cheated on me. A positive test this time round would confirm that, yes, I did actually have chlamydia and it was not a false-positive.

[Clairebert]

After re-reading my post, I think I may sound snarky. I wanted to say that I appreciate your advice Vance, and that I am very glad someone is reading and helping me deal with this as it is a very confusing time for me and I flip-flop between being hopeful and feeling betrayed.

I do very much hope that I had a false positive, I just... I can't seem to think of myself as that "lucky". I think cervical exams are 99.5% accurate (or somewhere around there) which makes it highly unlikely that I had a false-positive. My doctor told me that urine tests are somewhere between 90-98% accurate.

[Vance2335]

If the urine test was collected correctly they are less likely to give a false negative. So if the urine was collected and the person did not urinate within 1 hr of the collection then the test run will pick up the infection probably at a 99+%. Modern testing of course has flaws but false negative are not common. False positives are because different bacteria could show on a test and be mistaken for a certain infection.

I have been doing a lot of reading and speaking to a couple of people (not Dr's just people who work in the field) and they have said (personal belief) that when a chlamydia test is done in conjuction with a pap it tends to produce a higher rate of false positives.

I also see this a lot with people testing with a pap and getting a positive yet partner is negative. So I can only assume that these are actually false positives.

Keep me updated when he gets the test back. And no you did not sound snarky.

[Clairebert]

That's interesting, I hadn't heard that before. I've read on this forum somewhere that it may be possible that the tests are picking up on BV?

This may have nothing to do with it, but I guess I'll give a little added info about myself (lucky you!)

I have been prone to getting yeast infections from a fairly early age. When I was 16, and was not sexually active then but my brought me to the doctor when she noticed that my underwear in the dirty laundry had a lot more discharge than she thought was normal. The doctor said that I probably had allergies, and it's true. I'm allergic to silk underwear, latex condoms and certain types pads and tampons. I admit, I've never been too careful about the brands I use and sometimes I do get a yeast infection following my mensies from using a brand I'm sensitive to.
Whether or not this explain my test picking up on BV, I don't know. This theory seems to be highly debated in this website, but who knows...

[Clairebert]

Hey!

He got his results back, and they are negative again.
I'm relieved, I really do believe that I had a false positive. Nothing else really explains it, I think.

[Vance2335]

I would bet false positive.