Presumed infectious mononucleosis in a college basketball player.

A 20-year-old college basketball player was diagnosed as having acute infectious mononucleosis and was withheld from championship competition. Subsequent clinical, laboratory, and serologic evaluation revealed that he, in fact, had a latent infection with Epstein-Barr virus (EBV), a current viral syndrome, and a false-positive Monospot test. This case demonstrates the need to consider obtaining specific serologic titers for EBV to confirm a diagnosis of infectious mononucleosis and establish eligibility for return to play.