Epstein-Barr virus-induced lymphoma in a cardiac transplant recipient.

A monoclonal diffuse histiocytic lymphoma developed during the course of a serologically documented primary Epstein-Barr virus infection in a 22-year-old cardiac transplant recipient taking cyclosporine and prednisone. Throat washings revealed the virus at tumor presentation, and the tumor was shown to contain Epstein-Barr nuclear antigen-positive cells and the viral genome. Prolonged inversion of the T cell helper/suppressor ratio was demonstrated. A brief course of acyclovir appeared to halt viral shedding in the throat but had no apparent effect on the tumor.