Usefulness of The Test
The specificity of the test is high, virtually 100%, so a positive test is useful in confirming EBV. Rarely, however, a false positive heterophile antibody test test may result from toxoplasmosis, rubella, lymphoma and leukemia.
However, the sensitivity is only moderate, so a negative test does not exclude EBV. This lack of sensitivity is especially the case in young children, many of whom will not produce the heterophile antibody at any stage and thus have a false negative test result.
In the case of delayed or absent seroconversion, an immunofluorescence test could be used if the diagnosis is in doubt. It has the following characteristics: VCAs (Viral Capsid Antigen) of the IgM class, antibodies to EBV early antigen (anti-EA), absent antibodies to EBV nuclear antigen (anti-EBNA)
Read more about this topic: Heterophile Antibody Test
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