RESUMEN
BACKGROUND: Commercial immunoassays that detect IgG and IgM directed toward VCA and IgG EBNA are used in combination to assess EBV immune status. However, this strategy does not always confirm/exclude recent/past EBV infection or absence of immunity. OBJECTIVES: The aim of our study was to perform complementary investigations on samples with atypical EBV serological profiles, in order to identify the clinical situation they correspond to. STUDY DESIGN: EBV serology was performed using EBV VCA IgM/IgG and EBNA IgG LXL® DiaSorin assay. Complementary investigations included ELISA IgM VCA, immunoblots, CMV IgM/IgG and CMV IgG avidity, and EBV PCR. RESULTS: In our study, 12810 EBV serological results were analyzed, and 3580 atypical profiles were detected (28â¯%). Among these latter, isolated VCA IgG represented 42.9â¯%, the three positive markers accounted for 29.1â¯%, isolated EBNA IgG represented 18.5â¯%, isolated VCA IgM accounted for 6.4â¯% and positive VCA IgM & positive EBNA IgG represented 3.1â¯%. VCA IgG detected alone were specific in 100â¯% cases and EBNA IgG detected alone were specific in 91.7â¯% cases. VCA IgM detected alone were false positive or due to a cross reaction with CMV in 52.8â¯% cases. The pattern positive VCA IgM and positive EBNA IgG correspond to a false positive in VCA IgM, EBNA IgG or both in 83.4â¯% cases. Positive EBV VCA IgM/IgG and EBNA IgG were unreliable to detect active EBV infection in 66.7â¯% cases. DISCUSSION: Atypical EBV serological profiles may correspond to several clinical situations and complementary investigations allow to determine the immune status in more than 98.5â¯% cases.