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interpreting lab results

I had what seemed exactly like a primary outbreak of genital herpes ~7 days after a risky exposure.  3 weeks after the exposure my test results are

igg hsv1 22.0
igg hsv2 <0.9

Is it safe to assume the hsv2 result is a false negative and didn’t pick up the hsv2 antibodies since it’s only been 3 weeks?

Does the positive hsv1 result increase likelihood this is a false negative for hsv2?
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207091 tn?1337709493
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It can take up to 12 weeks to develop antibodies. It's probably just too early. The other possibility is that you have genital hsv1. Were your sores cultured to make sure it was indeed herpes?

Testing again later will help sort it out. :)
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Unfortunately the sores were not swabbed.  I will continue to test weekly going forward.  Is it the case that a gradually increasing (but still not confirmatory index value) would suggest being positive, or can it also be <.9, .9, and then all of a sudden +6.0, for example?
Finally, would a negative igg for hsv2 at 12 weeks be conclusive proof that my sores were not due to hsv2?  absent any further outbreaks, how can I be completely sure of what’s going on?  I guess this is another way of asking whether there is really any difference in reliability between an igg blood test and a WB test once I’m past 12 weeks?
No need to test weekly. There are false positives with the hsv2 IgG test, so to minimize your chances of that, test again in a month, not any sooner. 70% will test positive by 6 weeks.

Yes, it could jump like that. If you did a more frequent test, you might see a more gradual increase, but since results below a 3.5 have at least a 50% of being a false positive, you should wait and not look for gradual increases.

He WB test looks for 16 different antibody proteins. The IgG looks for 1. It's a large difference in reliability.

Is your hsv1 infection an existing one? What was your exposure that could have caused your infection?
I see.  I’m really just trying to figure out the fastest possible way of confirming for sure that I am positive.  So you are saying that it is possible at 12 weeks to test negative on an igg but positive on a WB?  If that’s the case, seems like the igg should really never be relied on…?

The exposure involved unprotected vaginal sex with a woman (I am a man).  There were no visible sores.  About 10 days later I developed a cluster of bumps, which turned to blisters, then crusted over and healed.  From initial bumps to healing  took around a week.  I also had many of the typical whole-body symptoms (with the notable exception of a fever).

I had never been tested for herpes so I have no way of knowing if my HSV1 positive result was a new or old infection.  Does this sound like it could be a newly acquired case of genital HSV1?  Is there a way to figure this out for sure other than waiting around for another outbreak and then rushing to the clinic to have it cultured?
Forgot to mention the cluster was at the base of my shaft.  
So if you had no oral sex, if this is herpes, it's hsv2. Hsv1 is transmitted to the genitals by oral sex, and you didn't have that. That means your hsv1 infection is pre-existing. At least half of adults in the US have it, 2/3 globally. You probably got it as a child, like most people, from an adult in your life. 90% have no symptoms, but are still infectious.

The fastest way to determine if this is herpes is to get an outbreak cultured if you get another outbreak. Within 24-48 hours, get it cultured. If this is a new hsv2 infection, you may get another outbreak sooner than you could get a conclusive blood test.

While the description sounds like herpes, the time from development to healing does not at all. A week is very quick. Did you use anything on it?

A positive IgG over 3.5 with symptoms, or a high score, is reliable. A negative one with no symptoms is reliable. The tests aren't perfect, by any stretch, but since the WB is expensive, we do what we can with what we have.

I know the waiting period is awful, and I get it - I'm never good at waiting. Just try to hang in there. Take this weekend and go do something fun.
Thank you.  I did receive oral sex during the encounter as well.  Forgot to mention that.  And it’s possible the time from apparat an eye to healing was a little longer than a week.  I’m not sure.  

Let me summarize and see if I have this correct:

1) While waiting another month to do an igg test would be more reliable, it’s quite possible that my body starts producing antibodies today and that I could get a high (>5) index value as soon as next week if I were to test again.  Correct?

2) Once I get a firmly positive result (something greater than, say, 4.0?), is it possible that a subsequent igg might show a negative result?

3) If my positive HSV1 result stems from an old infection, and I newly acquire genital HSV2, would that have an impact on the timing of the appearance of HSV2 antibodies?

4) If there were no oral sex and a woman already has genital HSV1, is it not possible for her to infect me with it by having unprotected sex with me?

Thank you for bearing with all my questions!
Okay, so testing at 3 weeks, and having received oral, it's possible that your hsv1 IgG could indicate a new genital hsv1 infection. You can get genital hsv1 from receiving oral sex from someone who has it orally.

Your number is a little high to be a brand new infection, but that's not a really reliable indicator.

"And it’s possible the time from apparat an eye to healing was a little longer than a week.  I’m not sure." - I'm not sure what you are trying to say here.


1) While waiting another month to do an igg test would be more reliable, it’s quite possible that my body starts producing antibodies today and that I could get a high (>5) index value as soon as next week if I were to test again.  Correct?

Yes, if that's 6 weeks from the encounter. I'm not sure how long it's been from the actual encounter now.


2) Once I get a firmly positive result (something greater than, say, 4.0?), is it possible that a subsequent igg might show a negative result?

Probably not, because you had symptoms.


3) If my positive HSV1 result stems from an old infection, and I newly acquire genital HSV2, would that have an impact on the timing of the appearance of HSV2 antibodies?

Maybe, by a week or two, tops.


4) If there were no oral sex and a woman already has genital HSV1, is it not possible for her to infect me with it by having unprotected sex with me?

It's possible, but really, really unlikely without symptoms. Ghsv1 doesn't shed often, and doesn't recur often, so transmission without symptoms is really, really unlikely. Most experts haven't seen convincing cases of this.

Most ghsv1 infections are from oral sex.



Tested again (igg) at 6 weeks post encounter.  Again negative (<0.9).  No symptoms of any kind since 10 days post encounter.  If I remain asymptomatic until 12 weeks post encounter and have another negative igg test at that point, can I draw any conclusions?  I suppose in that scenario it's possible that I'm one of the 8% in whom the igg misses the infection.  If that's the case, the only way to get conclusive answers would be to take a WB.  Correct?

Or maybe I just don't have it and the "outbreak" I had was something else?  I read that syphilis can be mistaken for herpes so I had a syphilis test done at 6 weeks as well, which came back negative.

Am hoping for conclusive answers here without having to take a WB but maybe that's just not in the cards...
Syphilis sores don't usually show up until around 3 weeks after the exposure, and last at least a few weeks. This isn't syphilis.

The possibilities here are that this is genital hsv1, maybe hsv2 (though I think that's unlikely if you test negative at 12 weeks), or it was an allergic reaction to something, irritation, a fungal infection, or a host of other things.

If you are negative for hsv2 at 12 weeks, you can take a WB test if you'd like, if you can't let go of that possibility. I'd probably take my money and run, but that's up to you.

Thank you.  Am trying to think through my positive HSV1 results…If my HSV1 is oral and old, is it still possible for me to contract gHSV1 if I receive oral sex from a woman that oral HSV1?  In that case I would have both oral AND genital HSV1.  Is that possible?
If you have oral hsv1, you have antibodies that protect you from getting it in another location. It would be extremely unlikely for you to get it genitally. I'd still not let someone with an oral outbreak give me oral sex, but other than that, you should be fine.

Update -- another negative HSV2 test at 8-weeks post-exposure.  Now I am beginning to wonder whether there actually IS a real chance that I don't have it.  So, to recap:

July 3 - unproteced oral/vaginal sex with a woman of unknown status
July 6 - noticed a solitary red "bump" on shaft
July 8 - noticed a solitary sore where shaft meets scrotum
July 10 - noticed what i thought was a solitary pus-filled pimple at top of pubic region.  i popped it and the next day it was a sore
July 12 - noticed two more red "bumps" on elsewhere on scrotum
July 14 - cluster of 10-15 red bumps form at base of shaft
July 15 - they turn to what look like blisters
July 17 - they crust over and scab
July 20 - everything pretty much gone (still have a visible "scar" from the original bump on July 6)

I also had some whole body symptoms throughout much of this timeline, mainly fatigue, achiness, and the occasional but passing moment of tingling/burning/itching on my genitals.  Nothing particularly painful or disruptive, but noticeable in the moment.  No fever at any point, no burning when urinating.  I also had a pretty bad cough and general cold throughout this entire timeline so that has made this hard to sort out the whole body symptoms.

Tests:

July 16 (3 weeks) -
HSV1 positive - index 22.0
HSV2 negative - index <0.9

August 9 (6 weeks) -
HSV2 negative - index <0.9
Syphilis negative

August 27 (8 weeks) -
HSV2 negative - index <0.9

No other symptoms since everything cleared up around July 20.

I know the igg will pick up HSV2 in ~70% of people by 6 weeks, but how does that number scale up to 100% in the time that follows?  At 8 weeks, does it pick up 80%?  90%?

Possibilities:
1. My "outbreak" was a newly acquired gHSV1 infection.  This would explain all test results thus far.
2. My HSV1 infection is old and my "outbreak" was a newly acquired gHSV2 infection, but I am one of the small number of people in whom the test won't pick up the infection until 12 weeks, or I am one of the very few people in whom the igg ALWAYS misses the infection.
3. I don't have HSV2 and my "outbreak" was something else entirely.  I was initially sure this couldn't be, but now I'm starting to allow myself to dream of this possibility...

What do you think?
Thanks for the update.

Possibilities:
1. My "outbreak" was a newly acquired gHSV1 infection.  This would explain all test results thus far.

Agree that this could be a possibility. Unfortunately, the only way to know this is if you get any other symptoms, get them cultured ASAP, within 24-72 hours.


2. My HSV1 infection is old and my "outbreak" was a newly acquired gHSV2 infection, but I am one of the small number of people in whom the test won't pick up the infection until 12 weeks, or I am one of the very few people in whom the igg ALWAYS misses the infection.

I think this is less likely, but only time will tell. If you wanted to, and you are negative at 12 weeks for hsv2, you could get a Western Blot test to officially rule out hsv2. If you decide on that, you can get your doctor to do it, or you can go through Terri Warren at Westover Heights, but you'll have to self-pay and it's expensive (several hundred dollars).


3. I don't have HSV2 and my "outbreak" was something else entirely.  I was initially sure this couldn't be, but now I'm starting to allow myself to dream of this possibility...

I think this is a decent possibility. At the very least, it may he genital hsv1, but it's really looking like it's not hsv2.

Thank you.  Do we have any data to help me quantify odds of this not being hsv2?  what % of infections are typically picked up by 8 weeks?  gHSV1 also sounds highly unlikely given how rarely it sheds/transmits…
We don't really know the week by week breakdown. We know it's somewhere between 70 and 92%. (92% since it misses 8% of infections.)

You received oral sex, so the chances of this being hsv1 are decent. If someone has ghsv1, that rarely transmits, but oral hsv1 easily transmits to the genitals via oral sex.

All clear, and thanks for that point about oral-genital HSV1 transmissibility.
You're welcome. :)
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