[Question #712] Percentage of false positives for HSV 2-specific AB IGG test

46 months ago
I have HSV 1, but am asymptomatic, so I have no idea whether I have it orally or genitally. I am negative for HSV 2. My values (type specific IGG test) are 5.97 for HSV 1 and <0.91 for HSV 2. I have been tested 3-4 times over the past few years and the values have stayed the same (I was tested frequently because I was in a long-term relationship with a man who was positive and symptomatic for HSV 2).

When I started dating my current partner, he said he thought he had been tested before and was negative for both, so I went on daily antivirals to avoid transmitting HSV 1 to him during kissing or unprotected sex. We have been having unprotected sex for approximately 2-3 months. He got tested last week and his results came back positive for both HSV 1 and 2 (type specific IGG test). His values are 24.4 for HSV 1 and 2.48 for HSV 2. I've read that with low positive scores (<3.5) for HSV 2, there is a high likelihood of false positives. Do you know what the percentage of false positives is for a 2.48 value? He has also never had any symptoms orally or genitally (no cold sores, blisters, etc.).

Thank you.
Terri Warren, RN, Nurse Practitioner
Terri Warren, RN, Nurse Practitioner
46 months ago
Yes, at 2.48, there is a little better than a 50-50 chance that this is a real positive.  He's right on the border.  He needs a western blot.  Our clinic is doing a study of IgG vs. western blot and can order that for him if he likes (westoverheights.com) at a Quest lab near him or he can order the test kit from University of Washington to be sent to him.  Is he really sure he's been tested in the past?  Lots of people think they have had an STD test that includes herpes but many do not. 

Terri
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46 months ago
Thank you, Terri. He is fairly certain he's been tested in the past, but it would have been 2 or more years ago. He is definitely interested in the study, so we'll follow up on the Westover Heights Clinic website for next steps. What causes false positives in the IGG test/why are they so common? And what are the chances there will be a cure for herpes soon (both 1 and 2)?

Thank you.
Terri Warren, RN, Nurse Practitioner
Terri Warren, RN, Nurse Practitioner
46 months ago
There appears to be another protein that some people have in their blood that looks like one of the proteins in the HSV antibody that trips the test in some people. 
There is no cure on the horizon that I know about, sorry. 
Yes, I think the western blot would be very useful for him - and for you!

Terri
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45 months ago
Sorry for a possibly stupid question, but just to be clear, when you said the western blot would be useful for me as well as for him, did you mean useful for my peace of mind or were you suggesting I also get the western blot? And how long is the study going on for (what is the window of time to be able to participate)? If he doesn't do it right away, I don't want him to lose the opportunity to have the test done since it seems fairly difficult to get it through most doctors.
Terri Warren, RN, Nurse Practitioner
Terri Warren, RN, Nurse Practitioner
45 months ago
I meant it would be useful for you to know his true status, not necessarily to know your own status which is likely to be correct per the screening test.  We can enroll 500 subjects in our study per the IRB protocol, and we have 120 so we have time, no worries there.  I'll be back later in May to continue the phone consenting visits that allow subjects into the study - we'll get you taken care of, for sure.

Terri
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