Morphological and molecular diagnosis of a fatal form of EBV infectious mononucleosis in a child.

Mortal cases of acute Epstein-Barr virus (EBV) infection in the form of mononucleosis have been seldom described and used to be related to complications of the disease. In this report, the case of a 3-year-old girl is described, with severe form of infectious mononucleosis, deceased in the course of respiratory-circulatory insufficiency with a sudden cessation of heart action. Particular attention was given to histological lesions, phenotype of inflammatory cells and to expression of proteins and EBV RNAs (EBERs) in tissues, examined using immunocytochemical techniques and in situ hybridization.