Serological diagnosis of Epstein-Barr virus infection: Problems and solutions

摘要

Serological tests for antibodies specific for Epstein-Barr virus(EBV) antigens are frequently used to define infection status and for the differential diagnosis of other pathogens responsible for mononucleosis syndrome. Using only three parameters [viral capsid antigen(VCA) Ig G, VCA Ig M and EBV nuclear antigen(EBNA)-1 Ig G],it is normally possible to distinguish acute from past infection: the presence of VCA Ig M and VCA Ig G without EBNA-1 Ig G indicates acute infection, whereas the presence of VCA Ig G and EBNA-1 Ig G without VCA Ig M is typical of past infection. However, serological findings may sometimes be difficult to interpret as VCA Ig G can be present without VCA Ig M or EBNA-1 Ig G in cases of acute or past infection, or all the three parameters may be detected simultaneously in the case of recent infection or during the course of reactivation. A profile of isolated EBNA-1 Ig G may also create some doubts. In order to interpret these patterns correctly, it is necessary to determine Ig G avidity, identify anti-EBV Ig G and Ig M antibodies by immunoblotting, and look for heterophile antibodies, anti-EA(D) antibodies or viral genome using molecular biology methods. These tests make it possible to define the status of the infection and solve any problems that may arise in routine laboratory practice.