[Question #553] HSV clically in past, IgG undetectable

42 months ago
Roughly 17 years ago I was clinically diagnosed with Genital HSV.  No cultures/serology performed.  There were dry sores and definite groin lymphadenopathy, though at the same time was told tested pos for chlamydia.  I think I may have had "outbreaks" later, though nothing like the typical vesicles in a textbook.  The groin LAD did not reoccur.  And over the years I've attributed any slight pimple, rash, etc to a possible mild outbreak. I've always told partners I had HSV 2.  I do not take antiviral suppression and, to my knowledge, have not passed it to any partner short or long term.  And frankly, I cannot remember my last outbreak. 

I am entering a new relationship and decided to get tested. Normal STI panels don't do HSV IgG in the primary setting, but I requested it in an online mail panel through StdExpress, Analytics group.  They use the HSV 1/2 type specific IgG Herpeselect AB.  My results for both HSV 1 & 2 were under the ref range (<0.90) which is interpreted as negative.  

I was surprised, so went to a trusted friend in the Virology dept at local university who said it's possible if the virus is dormant for more than 10 years IgG levels might drop to undetectable.  10 years seems arbitrary.  I did a pubmed search and found no such study or case report to back this up, and one referencing varicella IgG that verifies it stays positive for life.  What I've found here is 1/4 HSV 1 AB may give a false negative, but nothing related to HSV 2.

My questions:  have you seen or heard of this? Could I have a false negative?  If so, and what my friend says is true, this seems to be a public health risk that should be reported and documented or at a minimum an asterisk next to the results.  Should I be retested with a different lab? Am I now free of the disclosure burden?

Thanks kindly for what you do here.
Terri Warren, RN, Nurse Practitioner
Terri Warren, RN, Nurse Practitioner
42 months ago
there is a thing that can happen called seroreversion - going from positive to negative but it isn't common.  However, being misdiagnosed by physical exam only happens all the time and is wrong one out of 5 times (and you can find that one in the literature).  If you really want to know your HSV status, I would recommend a herpes western blot.  We are currently doing a study at Westover Heights Clinic comparing the results of the ELISA IgG to the western blot test, which is considered the gold standard of herpes antibody testing.  And yes, with the IgG, it misses one of four infections, compared to western blot.  I think a test missing HSV 1 is more likely for you than seroreversion (going from positive HSV 2 to negative HSV 2). The western blot does not do seroreversion.

Terri
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42 months ago
Terri-
Thanks for the fast and interesting reply.  I think for my peace of mind and the implications this could have for a future partner, I would really like to know.  I've researched online how to get a Western blot.  What I've found seems like a pretty convoluted and expensive process only offered by the UofWashington.  Is that right?  Would you be able to enroll me in your study? Believe it or not, I may be  heading your way for a prospective job and would be happy to participate.  
Terri Warren, RN, Nurse Practitioner
Terri Warren, RN, Nurse Practitioner
42 months ago
Of course you can participate in our study!  We are doing it with UW, and all the details are on our website, westoverheights.com.  You don't need to be in Portland to do it - we can have your blood drawn wherever you are.  I totally understand your desire to know completely one way or the other.

Terri
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42 months ago
I thought the study comparing ELISA IgG to WB had been done, with the former being 98% sensitive c/w 99.5%?  Maybe I saw that wrong.  Also, does the WB distinguish type 1 from 2?
I will look at the site.  Thank you!
Terri Warren, RN, Nurse Practitioner
Terri Warren, RN, Nurse Practitioner
42 months ago
Yes, the results that we have SO FAR are is that the HSV 2 IgG test picks up 98% of infections, compared to western blot, but we are continuing to enroll subjects - we are looking now for 460 more subjects!  The more we get, the more accurate we feel the numbers will be.  Yes, the western blot looks for both HSV 1 AND HSV 2. 

Terri
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