High incidence of ganciclovir-resistant cytomegalovirus infection among lung transplant recipients receiving preemptive therapy.

Preemptive antiviral therapy in transplant patients is thought to be less likely to lead to antiviral resistance than is routine prophylaxis. Cytomegalovirus (CMV)-seropositive lung transplant patients (R+) were assigned to receive pp65 antigen-guided ganciclovir therapy, and seronegative recipients of organs from seropositive donors (D+/R-) were assigned to receive initially preemptive and then routine ganciclovir prophylaxis. The incidence of infection with ganciclovir-resistant (ganR) CMV was assessed retrospectively. GanR CMV infection developed in 4 (9%) of 45 patients, at a median of 4.4 months (range, 3.1-6.6 months) after transplantation, and was more common among D+/R- patients than among R+ patients (3 of 11 vs. 1 of 34; P =.04). The incidence among patients who received preemptive therapy was similar to that among patients who received routine prophylaxis. All ganR isolates contained a UL97 mutation. GanR CMV infection occurs in nearly 10% of lung transplant recipients, despite preemptive antiviral therapy, and is more common among D+/R- patients.