Cytomegalovirus mononucleosis as a cause of prolonged fever and prominent weight loss in immunocompetent adults.

Four immunocompetent adults presented with protracted fever lasting > 6 weeks and severe weight loss, associated with primary cytomegalovirus (CMV) infection. Each patient had spleen enlargement, lymphocytosis and hypertriglyceridaemia, but recovered spontaneously. A further 20 immunocompetent patients with primary CMV infection were also reviewed, and all presented the usual clinical picture of CMV mononucleosis. It was concluded that CMV mononucleosis should be considered in the differential diagnosis in patients with prolonged fever and weight loss if lymphocytosis is present.