Heterophile antibodies are antibodies induced by external antigens. Some cross-react with self-antigens. For example, in rheumatic fever, antibodies against group A streptococcal cell walls can also react with human heart tissues. These are considered heterophile antibodies.

What does a positive heterophile antibody test mean?

A positive test indicates the presence of heterophile antibodies. This result, alongside a patient's symptoms, are used to make a diagnosis of infectious mononucleosis. A negative test may indicate that a patient does not have infectious mononucleosis.

What do EBV test results mean?

The presence of VCA IgG antibodies indicates that an EBV infection has occurred at some time recently or in the past. The presence of VCA IgM antibodies and the absence of antibodies to EBNA mean that the infection has occurred recently. The presence of antibodies to EBNA means that the infection occurred in the past.