What are the chances for 2 false negative herpeselect tests?

[medquestion07]

I'm hoping to get this question to Dr. HH, since it requires a lot of herpes observation. I was just wondering what the chances were for 2 false negative blood tests using Herpeselect. I had these tests about 10 and 12 months post my primary outbreak and they came back first HSV2: 0.9 and then HSV2:0.6 on the second test. The HSV1 score was both times very low as well (about 0.2). Thing is, I have had recurring lesions which at times I can remember having soreness in my groin and buttock preceding them (thus seemingly a prodrome). Importantly- I also had a positive herpes sore scraping sample done by a doctor though he MIGHT have used the Tzanck test which I have read is a weak test.

I unfortunately have not yet checked if indeed he used a tzanck test, but the result came on the same day as the sample was taken from me if that indicates anything. As much as I would like to think that my 2 negative Herpeselect tests indicate that I do not have HSV1 or HSV2, my positive sore scraping test and simply my experience of recurrent lesions which very much fit the bill of herpes lesions in their presentation (totaling about 5 recurrences over 14 months) really makes me think I indeed have herpes. I am just surprised by my two negative Herpeselect test results. I would really like to believe them, but my most recent outbreak with sores fits the herpes bill very well, as did the others. So I just want to know what % of people could have two Herpeselect negative tests in a row. To me the % chance seems absurdly tiny. Nevertheless the reality of my experience plus the positive skin scraping have me convinced I am HSV positive.

[H. Hunter Handsfield, M.D.]

The negative blood tests strongly that you are not infected with HSV-2.  A positive Tzanck test is not to be totally disregarded, but it is a highly unreliable test; even a classically positive results often are false.  (Almost no herpes experts use the Tzanck test any more; it is too unreliable.)

You don't describe the nature of your outbreaks, which would help judge the possibility you have genital herpes; if they are highly typical, perhaps the HerpeSelect results indeed are false positive.  But the more likely possibility is that you don't have herpes at all.

If/when you have additional outbreaks, you need to see a provider who is highly experienced in herpes and who has access to proper tests to detect the virus in the lesions, i.e. culture or PCR for HSV.  Those tests need to be done within 1-2 days of onset of a lesion in order to be accurate.  But until such testing confirms your infection, my bet remains that you don't have HSV.

Best wishes--  HHH, MD

[medquestion07]

Yes my lesions seem pretty typical. I have had a cluster of 2-3 adjoining lesions in the past and this time had three separate lesions, about half an inch apart on the glans and foreskin. They can ooze yellowish liquid on a reddish base. So pretty typical I feel, especially since I can remember at least 2 times that they were preceded by soreness in my groin area which seems to me a prodrome. I think that if you were to see them, and see my full case (multiple recurrences) in the end the overall diagnosis would likely be HSV+, again despite the fact I would love to believe my blood tests. Following your advice I will nevertheless get a new culture test done next time i have lesions.

If two blood tests are false negative in a row, does this mean that my HSV could be deficient in some way, thus will never test positive for IgG? To me it seems that otherwise, the chance for two false negatives in a row would be less than 1% given that error rates need to be multiplied when you test twice as per statistics. Thanks for your time.

[H. Hunter Handsfield, M.D.]

Your description indeed sounds typical.  Follow through on the culture/PCR advice -- and in the meantime, stay off antiviral therapy.

I can't speculate about whether your blood test would remain permanently negative, if indeed you have herpes.  Probalby not, but there are no data to answer that question with certainty.