Evaluation of a new Epstein-Barr virus Combi Test for rapid serologic diagnosis of infectious mononucleosis.

We evaluated the EBV Combi Test (Virion) in serum samples from 574 children with a clinical presentation suggestive of infectious mononucleosis (IM) and compared its performance with several other EBV serological tests. Out of 574 sera 66 gave an acute IM pattern, 406 gave a past infection pattern and 102 were found negative in the EBV Combi Test. Positive VCA IgM and VCA IgG IFA results, in the absence of EBNA antibodies, were found in 62 cases in which the EBV Combi Test gave an acute IM pattern. In addition, 4 to the 574 tested sera gave an acute positive result in the EBV Combi Test (two of them were VCA IgM positive and the other two VCA IgM negative but also EBNA negative). None of these four sera were CMV IgM or Toxoplasma gondii IgM positive. The heterophile antibody test was positive in only 28, and VCA IgM EIA positive in 44 of the 62 IM cases. These data confirm the necessity for an EBV serological diagnosis in children where the clinical diagnosis of EBV infectious mononucleosis must be confirmed or ruled our.