Epstein-Barr virus (EBV) infects virtually everyone by adulthood, and a lifelong latency is maintained. It infects children silently, whereas the majority of adolescents have
infectious mononucleosis (IM). Children who have IM before 5 years of age are often heterophil negative; EBV-specific
antibodies are required for diagnosis. On rare occasions the symptoms of IM may persist in a chronic or recurrent form, and fatal
infectious mononucleosis occurs rarely. Depending on the type and degree of immune deficiency and the time the
EBV infection occurs in the life cycle, various atypical outcomes can occur. Children with
primary immune deficiency can have fatal or chronic IM, malignant
B cell lymphoma, virus-associated
hemophagocytic syndrome,
aplastic anemia, or
acquired hypogammaglobulinemia. The various outcomes of the
EBV infections are likely governed by the immune response of the individual. The increased frequency of B cell
neoplasms in immunodeficient patients is likely due, in part, to EBV. Individuals with acquired immune deficiency disorders such as
AIDS or allograft recipients may develop malignant
B cell lymphomas which tend to be polyclonal, but which may progress through stages of oligoclonality to monoclonality. This conversion likely results from specific reciprocal
chromosomal translocations such as t(8;14), which is seen in
Burkitt's lymphoma. Detection of EBV in immunodeficient patients is achieved by EBV-specific antibody studies or isolation of virus by obtaining spontaneous lymphoblastoid cell lines from peripheral blood, isolating virus from throat washings, or identifying EBV genome by molecular hybridization techniques. Prevention of
primary immune deficiency by early detection and genetic counseling and monitoring of patients for occurrence of
EBV infection may lead to early treatment.
Acyclovir and immunoglobulin therapy can be of value in some patients with active
EBV infection.