CMV Viremia after Discontinuation of Valganciclovir Prophylaxis in Lung Transplant Recipients

Purpose Cytomegalovirus (CMV) remains a significant cause of acute morbidity following lung transplantation, and has been linked to the early onset of chronic allograft rejection. Most lung transplant centers utilize prophylaxis with valganciclovir (VGC) to prevent CMV infection. Long-term VGC therapy can be complicated by adverse side effects that include myelosuppression, leading to early discontinuation. We hypothesize that the risk of CMV infection following withdrawal of VGC will be affected by the D/R serology status. Methods We performed a single center, retrospective study of patients who received a lung transplant between January 1st, 2016 to December 31st, 2018. Patient information included gender; VGC discontinuation due to myelosuppression; time from transplant to VGC discontinuation; and time from VGC discontinuation to first detectable CMV PCR. Results A total of 112 patients received a lung transplant during the study period (table 1). All patients initiated VGC after transplant. CMV D+/R- patients also received CMV immunoglobulin every 2 weeks for 7 doses. 40 patients (36%) developed CMV viremia, with more than half of these cases occurring in CMV+/- recipients. All but two of these cases occurred following discontinuation of VGC. None of the cases of viremia were associated with end-organ disease. Conclusion Although recent data suggests that extending VGC prophylaxis up to 18 months in lung transplant patients may offer additional protection, the side effects may limit this practice. Incidence of CMV viremia following discontinuation was highest in D+/R- patients and in patients who discontinued therapy early, but there were no patients with end organ disease. These results support a VGC prophylaxis strategy where duration of therapy is based on D/R serologies coupled with weekly monitoring of CMV PCR for 16 weeks after VGC discontinuation.