conflicting IGG test results

[medques]

All 4 herpes tests that I refer to are the IGG Herpes Select Quest Diag. that diff. b/t type 1 & 2. 1st test on 5/19/06.  Result:Type 1 pos (4.93)& Type 2 neg (0.05).My b.f is only partner since neg test. We have had unprot'd sex since 12/06.Neither have had any symptoms,except what I think was a yeast infection in 01/07.Treated with dyflucan 2 x's.It went away in a couple of days each time,then came back in 2 wks. No culture taken.Seemed like yeast: white cottage cheese like discharge and all the other symptoms of a yeast infection. In 02/07 she prescribed 7 day yeast infection cream injections.It never came back.On 06/03/07,my b.f had an abrasion his penis after we had had alot of vigorous sex.Same night I noticed an abrasion on the inside lip of my vagina and both disappeared w/in a 2-3 days. During a regular physical, I told a NP about this & she ordered the same test as above on 6/6/07.No culture taken b.c abrasion was gone. Result:Type 1 pos (4.88) & Type 2 (1.50). She told me that I was pos for genital herpes. I had the same test thru Advanced Testing on 06/13/07.Results:Type 1 pos (>5) & Type 2 pos (2.64).My gyno and did the same test on 07/03/07.Result: Type 1 pos (>5)& Type 2 equivocal (1.05).
1.  Is 1.50 a pos result?What do the conflicting test results mean?Is it possible that I don't have type 2? Could the 1.05 equivocal result be a false one since I appear to have 2 positive tests?Should I have another test?

[H. Hunter Handsfield, M.D.]

In people with positive HSV-1 results, like you, mid-level HSV-2 results often are falsely positive.  That is, when the HSV-2 ELISA ratio is positive above 1.0 but below 3.5, there is about a 50% chance each that the person does or does not have HSV-2.

Since you haven't had clear clinical evidence of genital herpes--I agree the symptoms you describe don't necessarily mean herpes in either you or your boyfriend--most likely you don't have HSV-2.  However, it simply isn't possible to know for certain based on the currently available information.  There are 3 approaches to sorting it out:

1) Your bf could have a blood test.  Assuming he is your only partner over the past year, he would have to be the source of any HSV-2 infection (because your result was definitely negative last May).  So if his test is negative for HSV-2, that would effectively rule it out for you.  If positive, it would likely mean that you are infected as well.

2) You can have repeat HSV-2 testing by an entirely different method, such as the Kalon test (available in the UK, not yet widely available in the US); the BiokitUSA test, which is available; or a Western blot test, the gold standard. WB is available only at the University of Washington in Seattle, but your local lab will know how to refer a specimen for testing.  The main drawback of WB is that it is expensive (I think around $150, plus whatever handling fees come from your doc's office or the local lab) and might not be covered by insurance.

3) You can wait for new abrasion-like symptoms or other symptoms of herpes and see your NP or other provider immediately, within 1-2 days of onset, for a culture or PCR test for HSV-2.

These three approaches are not mutually exclusive.  If the cost isn't too big a deal for you, I suggest your bf get tested and you have blood sent for Western blot.

Good luck--  HHH, MD

[gracefromHHP]

Since your doctor uses quest labs you can also confirm your results with the herpes inhibition assay. It's test # 17170 for your doctor to order. It helps rule out false positives due to hsv1 infection.

grace

[H. Hunter Handsfield, M.D.]

Good point from grace.  I keep forgetting that Quest now offers the inhibition test.  It isn't perfect, but it's another option that can help sort out confusing HSV-2 results.