HHV-6 reactivation confusion

[JasonUT]

Hello,

I understand that HHV-6 reactivation and testing is a very debatable topic. With that said, my Quest Diagnostic labs have shown igg of 1:1280 and 1:320 and igm as negative. Per HHV-6 Foundation, this seems to be suspect for reactivation. What are other people's opinions on HHV-6 reactivation? Thanks

https://hhv-6foundation.org/patients/hhv-6-testing-for-patients

Quest lab report footnote:

Human Herpesvisur 6 (HHV-6) infects T-lymphocytes, and has been identified as an etiologic agent of exanthema subitum. Rises in antibody titers to HHV-6 have been detected during infection with other viruses. In seroepidemiology studies of the prevalence of exposure using serum screening dilutions of 1:10, the detection of IgG antibody in a mid-life population approaches 100%. Due to this high prevalence of HHV-6 antibody, correlations of single IgG titers with specific diseases are of little clinical value. Evidence of acute infection or reactivation of HHV-6 is demonstrated by a significant rise or seroconversion of IgG and IgM titers. This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. Nichols Institute, Valencia, CA. It has not been cleared or approved by the U.S. Food and Drug Administration. The FDA has- determined that such clearance or approval is not necessary. This assay has been validated pursuant to the CLIA regulations and is used for clinical purpose.
TESTING PERFORMED AT QUEST DIAGNOSTICS NICHOLS INSTITUTE 27027 TOURNEY ROAD VALENCIA, CA 91355-5386

 

[JasonUT]

HHV-6 Foundation:

IFA IgG test

Example: Titer 1:640
If the titer is highly elevated relative to healthy controls, it means that the patient may have had a recent infection or has a current chronic/smoldering infection. Quest Diagnostics and ARUP Laboratories are two of the only known laboratories in the USA to perform testing by IFA methodology. Their labs have a median antibody titer between 1:80 and 1:160 for controls. Other labs have much lower control titers.If the patient has an immune deficiency with low total IgG, then the antibody titer will not be elevated. If HHV-6 is the only antibody titer out of five viruses to be elevated above average, then this indicates possible HHV-6 infection.

IgM test

(ELISA or IFA)
Yes. IgM only appears during an active infection or for 2-3 months after an active infection.The absence of an IgM antibody does not mean you do not have a active infection. Chronic infections in various tissues can persist with no evidence of IgM.

 

[Hip]

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