Seroconverting

[34&tired]

Hi!

 

I believe I was exposed in late Sept of last year. I had been tested for H in the past- all negative. Swab was POS, blood neg.

 

I had blood work drawn in April and recently. IgG is negative for both types. 

 

It's been almost 10 months and I know I do not have HIV. (Was tested in Jan and again in June.) What could be the deal? Could it be a lab error with the swab? Does my body just blow at making antibodies? 

 

 

[tiredandlonely]

Do you know what the swab was positive for? HSV-1 or HSV-2? It is rare to get a false positive with a swab unless there is some sort of lab mix up.

After your positive swab, did you take antivirals? If so, how long did you take them for/are you still taking them? Antivirals can interfere with seroconversion (but if you have been off them for at least 12 weeks, your test should be accurate).

Have you had any symptoms since the symptoms you had swabbed? 

Do you know for sure if the person who you believe exposed you had HSV? If so, which type?

The IgG for HSV-1 misses up to 30% of infections, so if your swab was positive for HSV-1, an IgG may miss this. 

As I'm sure you know, the most reliable blood test for herpes is the Western Blot, so if you really want to confirm your status (especially if it's HSV-1), this may be the  best way to go. 

 

[34&tired]

Thank you for the reply!

The swab was positive for HSV2.

I've been on antivirals as a prophylactic until the Dr gets this sorted out but not the whole time. I was told they shouldn't interfere with antibody production?

The person I think exposed me told me recently he never had any sores I described. He said he also recently had blood work and it was negative. 

Is there ANYTHING else that can cause small ulcers? I know the swabs are highly accurate but I also know a degree of human error exists. 

Still, I don't understand how I wouldn't have ANY IgG. It wasn't even in the questionable rage.

[tiredandlonely]

Antivirals can interfere with seroconverting (you can read about this at the Westover Heights website if you are interested), especially if you had started them immediately after experiencing symptoms, because they can suppress the virus so much that your body doesn't have a chance to mount an immune response. 

But you mention that you haven't been on them the whole time, and in that case, your body should have had a chance to mount an immune response. Can you clarify if by "not the whole time" you mean you took like a week or 2 off from them, or if there were a few months in there when you were not on them?

There are other things that can cause small ulcers, but only HSV-2 would cause a positive swab. Do you know if your swab was done by viral culture or PCR?

Pretty much all reliable sources I have seen state that a positive viral culture is definitive for diagnosis purposes. Yes, a degree of human error exists, but when we talk about the margin of error on a lab test like IgG, it's not human error that we're considering - it's the error rate that is inherent to the test. Depending on the manufacturer of the test that was used for you, IgG misses 8% of HSV-2 cases. 

Viral cultures are not 100% accurate. They can often be falsely negative - especially if you wait several days to have a sore swabbed. But I can't even find a "false positive" rate published for these tests - they're not looking for a specific antibody - they are looking for the actual virus. If the test detects the virus, it is there. 

When you say there is a degree of human error, what you are saying is that you are hoping that the lab made an error. 

This is possible - human error is always possible - but I suspect it would be unlikely (though again, not impossible).

I know this is not what you want to hear. There are other things that can cause small ulcers. Genital herpes would be the most likely cause, but they could have been caused by other STIs or bacterial or yeast infections. Did you start taking antivirals when you developed the ulcer(s)? And if so, did they go away shortly after taking them?

Just because the person who you think exposed you has never had sores does not mean he does not have HSV-2 (as I'm sure you know, 80% of people with HSV-2 don't experience symptoms). Also, I am curious if he had a regular STD panel (which does not include herpes) and his doctor just told him that he was negative for everything, or if he actually had an HSV blood test.  Do you know?

If I were in your position, I would stop taking the antivirals for 3 months and then I would redo the IgG test. If the IgG test was still negative, I'd do the Western Blot. If the WB was negative, I would believe that result (negative results on the WB are over 99% accurate) as long as I didn't experience any herpes-like symptoms (itching, tingling, burning, ulcers, sores, etc).

If you stop antivirals and develop symptoms, then you can have the symptoms re-evaluated for herpes or some other infection, and you can always go back on antivirals, so the risk with this approach is fairly low.