STDs Expert Forum
Western Blot Fail
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The STD Forum is intended only for questions and support pertaining to sexually transmitted diseases other than HIV/AIDS, including chlamydia, gonorrhea, syphilis, human papillomavirus, genital warts, trichomonas, other vaginal infections, nongonoccal urethritis (NGU), cervicitis, molluscum contagiosum, chancroid, and pelvic inflammatory disease (PID). All questions will be answered by H. Hunter Handsfield, M.D. or Edward W Hook, MD.

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Western Blot Fail

I was tracking Insight Vid's posts, as I found his situation curious.  I would be interested to see how a Western Blot and Elisa stack up.  There was a question there yesterday about some WB taking longer than others for reasons unknown.  The site said something to the effect of 20% or blood takes an additional week or so.  I would also like to know why that is?

Personally I have never been tested for any STD's but have always practiced safe sex.  This site has taught me alot.  I plan to use some information to teach my teenage sons more about safe sex.  Is there any advice you would offer to young people in particular?  I suppose condom use would be number one...
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239123_tn?1267651214
Welcome to the forum.  But you're going to have to provide some more information.  I am unaware of what other thread(s) you are referring to and do not find a MedHelp username "Insight Vid" or "Vid".  Also, the moderators are not expected to have read other threads before responding to new questions.  Please summarize exactly what you don't understand about WB and ELISA testing.  Also confirm that you are asking about HSV testing, not HIV -- in which case you'll need to re-post a question on the HIV Prevention forum, not this one (as clearly stated in the statement at the top of this forum).

Regards--   HHH, MD
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Oh, it was:

Does the UofW WB produce false positives?
by InsightVid, Sep 18, 2010 11:51AM

But that question was a post that seems to have been deleted.  He/She asked why on the UofW Herpes WB info sheet that reads:

The test is an overnight assay and preliminary results ready on most sera 3-5 days after receipt in the lab. About 20% of sera require further testing, which requires an additional 5-7 days.

I guess I'm curious to how to the difference of mechanics in Elisa vs WB and what would be the reason for the extra testing.  It was just a curiosity.
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239123_tn?1267651214
OK, thanks for the update.  When a thread is deleted and username can't be found, it usually means that the user has violated MedHelp's rules in an important way, such as one person found to have 2 or more usernames; or excessive anxiety-driven posts.

Western blot tests are read visually, i.e. the technician interprets dark "bands" on a white paper or plastic strip; the bands mark antibody to specific multiple HSV antigens.  To diagnose HSV-1 and 2, the technician looks for bands of antibody to HSV glycoprotein G-1 (gG-1) and gG-2, respectively.  About 80% of the time, a quick inspection is sufficient to be certain about presence or absence of gG-1 and gG-2 bands.  The other 20% there is uncertainty, because a faint band may (or may not) be present, or there are nonspecific or atypical bands that may be difficult to interpret.  Such specimens may then be inspected by a senior/supervising technologist, or may be subjected to higher-tech analysis in an optical density reader.

In such situations, the final report usually is definitive -- although a certain proportion of WB tests are difficult or impossible to interpret in a definitive way.  In that case, the UW lab usually is prepared to accept a second specimen and test it at no additional cost.  Even so, some result remain uncertain.

Regards--  HHH, MD
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239123_tn?1267651214
I found the other thread.  I'm not sure why one of the forum moderators deleted only InsightVid's last comment/question; I reinstated it.
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Thank you for the Reply Dr. Handsfield.  I have one more question if I may.  I have read information on HSV PCR spinal fluid testing.  This seems extreme to me.  In any case, what is the accuracy of such a painful process?  What percentage of PCR spinal tests give false negatives/false positives?  Wouldn't HSV only be present in spinal fluid when someone is 'shedding'?
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To be clear, what are the percentages of accuracy for HSV types 1 and 2.
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239123_tn?1267651214
HSV sometimes causes meningitis (usually HSV-2) or encephalitis (brain tissue infection, usually HSV-1).  In patients with symptoms of such problems, cerebrospinal fluid is tested for HSV by PCR.  

This question is irrelevant to diagnosing genital herpes.  However, it suggests you are delving far too deepling into the internet for information that will most likely confuse you (as this information did) or upset you.  I suggest you sit back, await your test results, and otherwise stop worrying and stop searching for more information.

Please do not post anything else on this forum or thread until your test results are available.
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