Mixed Test Results

[Confused_in_Seattle]

Dear Dr.-

A couple months ago, I received news that I tested positive for HSV-2. I'm not sure which test I was given, but when I asked the nurse, she said it was the blood test that was the more accurate of the two. Anyway, when I went in to get a confirmation test done, via Western blot, I noticed my medical forms said my test showed the numeric value for the first blood test was between 1 and 3 or so.

I waited about 2.5 weeks to hear back from my Western blot test, which just came in the other day. This test showed I was negative for both HSV-1 and HSV-2. The guy on the results hotline read my chart verbatim and it said that I was negative for both (and that I had never been exposed to either viruses, whatever else that may add). He also said that even though this test is not FDA-approved, it is considered the gold standard for herpes testing.

I managed to call the Virology Clinic at the University of Washington to ask them some questions about my situation and the woman who answered the phone simply said, "Congratulations, you're negative." She also told me that there is a high prevalence of false positives for results such as mine (falling within the 1 to 3 range), something the person who first told me I was "positive" for herpes neglected to tell me.

Anyway, I guess my question is, can you simply provide your thoughts on this scenario? Am I, in fact, negative for HSV-2? Is the Western blot truly the "gold standard"? Are there a lot of false positives for results that I originally had in the first blood test?

Thanks so much!

[Terri Warren, RN, Adult Nurse Practitioner]

I would definitely believe this western blot result.  I don't believe that you need to retest.

Terri

[Confused_in_Seattle]

Well, turns out I took a look at my charts and the ELISA results are documented as follows: "Positive, Index >1.1-3.0 (Presumptive Infection)"

While my Western Blot states: "Negative for antibody to HSV-1 and HSV-2 by Western Blot. No evidence of past infection with HSV-1 of HSV-2."

I talked to a nurse from the STD Clinic today who suggested that to be absolutely sure, I might think about taking the Western Blot test again in 6-9 months.

Any thoughts? Sorry to pester with follow-up questions. :(

[Terri Warren, RN, Adult Nurse Practitioner]

It does matter.  I would definitely trust the western blot

Terri

[Confused_in_Seattle]

Yes. It has been over four months since my
last exposure, Which was an
oral exposure only (not sure if that matters that much).

[Terri Warren, RN, Adult Nurse Practitioner]

The most important question here is when was the last time you could possibly have been infected with herpes?  If you test too early after infection, the screening ELISA test that you had done could pick up early infection where the western blot did not.  I would advise that before taking the western blot, you wait at least 4 months for an accurate test.  If you are negative by western blot for both, and you have waited 4 months and your first ELISA value was between 1.1 and 3.5, then I would consider the western blot the accurate result here.

Terri