Treatment of life-threatening Epstein-Barr virus infection with acyclovir

Two pediatric patients with life-threatening Epstein-Barr virus infections were studied immunologically and treated with acyclovir [9-(2-hydroxyethoxymethyl) guanine]. The patient with chronic active Epstein-Barr virus infection who experienced massive hepatosplenomegaly, pancytopenia, and failure to thrive demonstrated abnormalities of T and B lymphocytes. A second patient, with the X-linked lymphoproliferative syndrome, experienced a rapidly fatal course of acute Epstein-Barr virus infection which typifies this yet undefined immunodeficiency to Epstein-Barr virus. In each case, objective evidence for clinical improvement or antiviral effect of acyclovir treatment was not apparent. Abnormally productive Epstein-Barr virus infections did not appear to play a major role in the clinical syndromes observed. Current studies are focused on treatment of immunologically normal patients with early complicated Epstein-Barr virus infection.