Accurate Herpes Diagnosis?

[turtle_dove]

Hi There,

I'm a female in good health that slept with someone who apparently was exposed to Herpes. One of the girl's that was  sleeping with him contracted it 2 1/2 months later. I got a blood test done here in Canada, -pardon me- Sereolgy done, as I had no symptoms, and neither does my current boyfriend. I came back negative for HSV-1, and positive for HSV-2. However, I have not recieved my ratio of antibodies yet. I called the Dr. and she said that the lab doesn't give ratios, but only 'positive' or 'negative' results. I don't believe that, so I'm having another Dr. look into that today. How accurate would this test be, as I came up negative for HSV-1? And what is the ratio to possibly have a false-positive result? I thought that the HSV typing was just to see if you had ever been exposed to the virus, meaning that you have been exposed, but don't have it? Also, the higher the ratio-the more you have it, or the more symptoms you have? I'm sure thnigs in Canada are alot different there testing wise in the states, so if there are any blanks, please feel free to ask :)

Any help on this would be much appreciated!

Thanks!!

[H. Hunter Handsfield, M.D.]

There are no useful data on this for the HerpeSelect immunoblot.  You could ask the lab, or ask your doctor to do so, whether the gG2 band (the line that indicates HSV-2 antibody) was definite and strong-looking, or if it was perhaps weak and faint.  If faint, maybe a false positive result.

You also could request repeat testing by the HerpeSelect ELISA test, which give the numerical value I described above; or you could have another test with the BiokitUSA test (I don't know if it's marketed in Canada, e.g. as BiokitCanana?), which is a pretty good tie-breaker. But why mess around with the less certain tests?  See above about Western blot testing.

[turtle_dove]

So what is the percentage that it could be wrong?

[H. Hunter Handsfield, M.D.]

I stand by the conclusions in my last two comments.  Perhaps not definite, but very likely.  Sorry.

[turtle_dove]

F*ck! This is not good. If I have it I will be f-cking devestated. I hope the 2nd test confirms that I don't...is it really safe to assume I do have it then, Doc?

[H. Hunter Handsfield, M.D.]

"Better" is relative.  It actually misses more HSV-2 infections than the Focus tests do (either immunoblot or ELISA), but still is considered the gold standard test for HSV antibody.  If WB is positive for HSV-2, it will confirm you are infected.  If negative, it will be somewhat less likely you have it, but still possible.

[turtle_dove]

Is the Western Blot better than the Focus Immuno Test?

[H. Hunter Handsfield, M.D.]

Aha!  The Focus immunoblot is done less frequently than the ELISA, but it measures exactly the same antibody.  Unlike the ELISA, which gives a number, the immunoblot gives a visual signal, similar to a Western blot.  I have less experience with it, but most likely it is a true positive result.  I'm afraid you'll need to go forward with the assumption you have HSV-2.  However, if you or your doctor remain skeptical, a confirmatory Western blot test always is an option.

[turtle_dove]

Sooo...I just spoke with my Dr. and she said they did the 'Focus Immuno Blot' test. She says its superior to The Western Blot Test? So that is why she didn't get a ratio... Is this test more accurate?

[turtle_dove]

Yeah, that's true. So anything abouve 3.5 is a confirmation, correct?

[H. Hunter Handsfield, M.D.]

Don't take my comment about HSV testing as critical of most Canadian health care providers, only the public health community (and not all of those); and I'm only talking about herpes.  I doubt there is much difference between the US and Canada in diagnosis and management of most STDs and yeast infections.  It's always hit or miss, however; in both countries, some doctors are up to speed and others are not.

[turtle_dove]

Hi Dr.,

Thanks for your responses. I know, I really hate the whole head-in the-sand additude about testing here in canada. The worst that happened once was my best friend was diagnosed with Ghonnera (I know that's the wrong spelling, sorry) and it turned out to be a yeast infection. Anyway, I will push harder to get my ratio and fill you in with it if you're interested. That you soo much for your help, you have no idea what this means to me :)

Take Care,

TD

[H. Hunter Handsfield, M.D.]

If the doctor doesn't even get the numerical result, I doubt she really knows whether your result is intermediate or not.  Anyway, most doctors and some labs are completely unaware of the newer research data on los-positive ELISA values and the high chance of a false positive result for values under 3.5.  This might be especially so in Canada, where head-in-the-sand attitudes about HSV blood tests among the public health community apparently have resulted in much less testing than in the US.  It's a good bet that the lab and the doctor are simply relying on the official interpretation of the test, as suggested by the manufacturer, and not the newer research.

So I suggest you continue to press for the numerical result.  You or your doctor will need to phone the laboratory directly.

The explanation for the discrepancies in test interpretation were discussed in the following thread:  http://www.medhelp.org/posts/show/593272, written in a way intended to be understood by health care providers.  In addition, here is a link to the abstract of one of the research studies on which proper test interpretation is based:  http://www.ncbi.nlm.nih.gov/pubmed/16225691.  If your doctor is the sort who will appreciate being educated by her patients, consider printing them out and discussing it with her.  

[turtle_dove]

Hi Dr,

The Dr. said that she doesn't get the numerical ratio. But that they only go my pos and neg, and she said that my ration was high enough to be labeled positive as a pose to intermediate....

[H. Hunter Handsfield, M.D.]

You are correct that the laboratory likely has a numerical ELISA ratio value, even if it only reports the conclusion (positive or negative) to the doctor's office.  In the past, my recommendation was that the lab's policy is the right one -- lots of confusion can result from the numerical result, and many patients only need know the conclusion.  But in more recent years, as we learned that some officially positive results are false if the ELISA ratio is on the low side, I now support the report of the numerical result both to the provider and, at the provider's discretion, to the patient.

Since you do not know your HSV-2 ELISA ratio, I simply cannot comment on the likelihood that you are infected.  The probability ranges from 10-20% true positives at ratios of 1.1-1.2 (even though these levels are technically positive) to almost 100% at ratios of 3.5 and higher.  The ELISA ratio is entirely unrelated to symptoms.  People with severe and frequent outbreaks can have low-ish values, and asymptomatic people often have high ones.

That you had sex with someone with HSV-2 does't mean very much.  Since so many asymptomatic people have HSV-2, lots of people have had sex with infected partners without knowing it.  So knowing about a particular partner doesn't make much difference.

Finally, blood tests definitely do not distinguish between "exposed" and infected people.  If you are exposed but don't catch the virus, the blood test remains negative.  A truly positive result indicates the person has been infected; and since HSV infections never go away, it means they continue to carry the virus.

If you can find your ELISA ratio, I will be happy to comment further on the likelihood you are infected.  Best wishes--  HHH, MD