Human Herpesvirus 6 (HHV-6), IgM

CPT: 86790
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  • HHV-6 IgM Antibody

Expected Turnaround Time

1 - 6 days

Related Documents

Specimen Requirements




1 mL

Minimum Volume

0.5 mL (Note: This volume does not allow for repeat testing.)


Red-top tube or gel-barrier tube

Storage Instructions


Stability Requirements



Room temperature

14 days


14 days


14 days

Freeze/thaw cycles

Stable x3

Test Details


The detection of anti-HHV-6 IgM or a fourfold rise in anti-HHV-6 IgG supports a clinical diagnosis of HHV-6 infection. Human IgM antibodies to HHV-6 antigens are detected by indirect fluorescent antibody (IFA) assay. Diluted serum is incubated on a slide containing infected T-lymphoblasts. If specific HHV-6 antibodies are present, they remain bound, are then labeled by an antibody conjugate and finally detected by fluorescence microscopy.

Human Herpesvirus-6 (HHV-6) is a distinct herpes virus that typically causes a self-limiting illness in patients who are not immunocompromised. In some patients, especially if immunocompromised, HHV-6 can cause febrile convulsions in infants, encephalitis mononucleosis-like symptoms, and hepatitis.


IgM antibody only appears during an active infection or for 2-3 months after an active infection. However, the absence of an IgM antibody does not mean the patient does not have an active infection. Chronic infections in various tissues can persist with no evidence of IgM.

This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration.


Immunofluorescence (IF)


Order Code Order Code Name Order Loinc Result Code Result Code Name UofM Result LOINC
138529 Human Herpes Virus Type 6 IgM 25417-7 139587 Human Herpes Virus Type 6 IgM 25417-7

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