- Last Update On : 2013-01-12
Antibody to Early Antigen is detectable within 3 to 4 weeks after an acute EBV infection and correlates with severity and duration of disease. High titer Early antibody correlates with more severe disease. Antibody level slowly decreases, but may persist for several years in some patients. In the absence of detectable IgM-VCA, an acute EBV infection is suggested if IgG-VCA and IgG-Early tests are positive, and IgG-EBNA is negative. Approximately 30% of patients with infectious mononucleosis never develop IgG antibody to early antigen.
Reactivation of latent EBV can occur in immunodeficient or immunosuppressed patients. IgM-VCA antibodies may be transiently positive concurrently with rapidly rising high titers of IgG-VCA. IgG-Early titers will also be high and increase at least fourfold over time. Serology performed for the diagnosis of reactivated EBV infection in patients with non-specific symptoms or in immunocompromised patients must be interpreted cautiously. False positive early antigen may occur due to many of the same factors that cause false positive VCA IgM (see EBV Antibody Panel). Results may also be altered in patients treated with corticosteroids, other immunosuppressive agents or gammaglobulin.
Early antigen is not included in the Epstein-Barr Virus Antibody Panel and must be requested separately. Reference Range is less than 1:10.
Specimen requirement is one SST tube of blood.