Chronic Epstein-Barr virus infection associated with fever and interstitial pneumonitis. Clinical and serologic features and response to antiviral chemotherapy.

Two patients developed fever, interstitial pneumonitis, and pancytopenia associated with extremely high titers of antibody to replicative antigens of the Epstein-Barr virus. In contrast to most patients seropositive for Epstein-Barr virus, neither patient had an antibody response to the Epstein-Barr nuclear antigen K polypeptide. In addition, virus isolated from one patient had a deletion of the B95-8 type in the EcoRI C region of the genome. An etiologic relation between Epstein-Barr virus replication and the clinical manifestations of this syndrome is further shown by the response of each patient to acyclovir therapy. These patients have a new Epstein-Barr-virus-associated syndrome and provide additional evidence that acyclovir may play a role in therapy for selected patients with Epstein-Barr virus infection.