[Histopathologic features of cytomegalovirus lymphadenitis in the "immunocompetent" patient. Report of 7 cases].

The authors report seven cases of cytomegalovirus lymphadenitis in apparently immunocompetent patients. One patient presented with an infectious mononucleosis-like illness. The main presentation of the others was isolated cervical lymphadenopathies. The lymph node pathology showed aspecific lymphoid hyperplasia, resembling the human immunodeficiency virus related lymphadenopathy, associated with diagnostic inclusion cells. Infected cells were confined to areas of monocytoid B cell hyperplasia in all cases whereas exceptionally observed in germinal centers. Because of their variable appearance, serial sectioning was frequently necessary to disclose their characteristic features. In all cases, immunohistochemistry using an anti-cytomegalovirus antibody was positive and revealed more infected cells than detected by morphology alone. Except for the endothelial cell, the nature of infected cells remained undetermined. An alteration of the antigenic expression as a consequence of cell infection might be responsible for immunohistochemistry failure in the cell characterization.