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EBV antibodies - converting U/ml to titer ratios?

Messages
93
Location
UK
Hi,

My illness started with glandular fever over a decade ago, and these are my recent EBV results:

EBNA IgG antibody * 25 U/ml (< 5 U/ml Negative)
VCA IgG * >750 U/ml (<20 U/ml Negative)
EBV VCA ab.(IgM) <10 U/ml (<20 U/ml Negative)
EBV Early Ag ab.(IgG) * >750 U/ml (<20 U/ml Negative)

I have no idea whether these are the same as the titer ratios given by Montoya here: https://www.ncbi.nlm.nih.gov/pubmed/23080504

(i.e. simply 750 equiv to 1:750?)
or whether I would need to convert these to know whether I have any indication to try antivirals. Can anyone help?

Many thanks
 

Hip

Senior Member
Messages
17,824
I've scoured the Internet looking for ways to convert U/ml titer index numbers into titer ratios such as 1:640, but never found anything.

In any case, even if your results were given in titer ratios, you cannot assume that titers given by one lab will be the same as titers given at another lab. And labs sometimes change the testing kits they use, so even the titers from the same lab 5 years ago may not map onto the titers they currently report.

So you would have to use exactly the same lab test if you want to compare to the titers given in a published study.


Dr Martin Lerner says ME/CFS patients have an active EBV infection if there are elevated antibody titers in the VCA IgM and/or EA IgG diffuse tests by ELISA. Refs: 1 2

Your VCA IgM is low, but your EA titer of > 750 U/ml looks high, at least in relation to the 20 U/ml threshold for negative (but I am not sure if yours is a EA diffuse, and not sure whether this matters).

So that looks like you might be positive for chronic active EBV by Lerner's criteria. Though that's just my guess, because without accurate threshold figures, it can only be a guess.


In the paper you citied, Prof Jose Montoya says a VCA IgG titer of 1:640 or higher and a EA IgG titer of 1:160 or higher indicates an active EBV infection in ME/CFS.

Your VCA IgG titer of > 750 U/ml looks high, at least in relation to the 20 U/ml threshold for negative. And as mentioned your EA IgG titer looks high. So it looks like you might be positive for chronic active EBV by Montoya's criteria too. Again, it's just my guess.
 
Messages
93
Location
UK
Thanks @Hip really appreciate your opinion. I have also been getting rashes which I think now may be linked to EBV reactivation, plus I am recently folate deficient which I suspect may be depletion by the virus or body sequestering it away from the virus, I need to do some more reading! I would be interested to hear from any others who get a recurring ringworm-like rash.