Clinical impact of ganciclovir-resistant cytomegalovirus infections in solid organ transplant patients

Clinical consequences of ganciclovir resistant cytomegalovirus (CMV) infections were studied during 2 large prophylactic trials consisting of 100 days of valganciclovir or ganciclovir prophylaxis in solid organ transplant (SOT) recipients. The first one involved 301 high-risk (CMV donor seropositive/ recipient seronegative) SOT recipients excluding lung transplants followed for 12 months, whereas the second one involved 80 lung transplant patients evaluated over 6 months. Among the 7 patients (4 non-lung and 3 lung transplant patients) carrying viruses with known ganciclovir resistance mutations in blood, adverse clinical outcome was only observed in the lung transplant recipients. Additionally, no CMV resistance mutations were observed in non-lung transplant patients receiving valcanciclovir.