[Question #8248] WEstern Blot

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47 months ago
I am trying to get some clarification on the Western Blot test. I was under the assumption that the University Of Washington recommended waiting 12 weeks from last sexual encounter prior to testing.  My first question is that my partner got the Western Blot as a confirmatory test due to low Igg positive score.  He waited approximately 20 weeks before being tested with the WEstern Blot and he was not taking anti viral medications and never had symptoms I just requested that he get a full panel STD test before we engaged  in sexual activities/sex. His score came back indeterminate and I know the UW says it can either be because he has a protein that looks like HSV or he hasn’t had enough time to seroconversion. That is confusing to me when they first say that waiting 12-13 weeks should give you a 99% accurate score for HSV 2. Also I read a comment by the CDC that was confusing and it read as “in instances of suspected recent acquisition serologic testing within 12 weeks after acquisition may be associated with false negative results. So does that mean that even if he was negative and got the WB after 12 weeks it could still be false?

My second question is, Do you really think it is necessary to repeat the test. It is a very expensive test and not easy to do. But I need to be 99.9% sure that he is negative. Can I be assured that he is 99.9% negative from his indeterminate because he waited 5 months, had no other sexual encounters and was not on antivirals? In all your years of experience as experts, Has there been any cases of anyone getting an indeterminate and then it turns positive?  Have you ever seen anyone take longer than 5 months to seroconvert? 

We had received counseling that he really didn’t need to re-test and should consider himself negative. Against my better judLike I said earlier I don’t want to put myself at any unnecessary risk but if there really isn’t a need to do the test I don’t see putting us through that as a couple as it was extremely stressful.  
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Terri Warren, RN, Nurse Practitioner
46 months ago
So he definitely has waited long enough.  You know he's waited long enough and so does he but UW has no idea how long he has waited so that's a standard reply that goes to anyone with an interderminate.  Does that make sense?

So the deal is that if he repeats the test and it is still indeterminate, he should consider himself negative. 
I have yet to see an indeterminate go to positive on the follow up blot if someone has waited 12weeks and has not taken long term antivirals.
I think he's fine.  That's a professional opinion, not a promise, but I wouldn't retest under those circumstances.

Terri
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46 months ago
Ok thanks Terri all of this stuff with these tests are so confusing sometimes I just want to make sure I’m making the right decision  and spending 1000$ for something that probably won’t change the results doesn’t make sense. 

If we are not having sex with other people do I need to protect myself with a condom? I’m not huge fan as they generally give me yeast infections 
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Terri Warren, RN, Nurse Practitioner
46 months ago
I understand that this can be confusing, yes. 
If we make the assumption that his indeterminate represents a negative, which is very likely but not 100% promise, then I don't think you need to use condoms,no.

Terri
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46 months ago
I guess nothing is 100% certain but I think we can feel pretty confident that in over the 30 years you have never seen an indeterminate go positive I know that you can’t tell him he is negative  but I think this is a strong indicator that he is especially since he was well past the 12 weeks and that he would be the only one to go positive. Is there any other test he can do that wouldn’t involve waiting 3 months that he could compare to the first blot?  I’m not sure it matters at this point since we did end up having sex but I just hate the “very likely” I want to be sure I don’t end up with something 
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Terri Warren, RN, Nurse Practitioner
46 months ago
There is no other test that I would recommend, no.  And I agree that it is very unlikely that he is infected - I would say well over 95%. 

Terri
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