Background: Antiviral prophylaxis is commonly used in recipients of solid-organ transplants with the aim of preventing the clinical syndrome associated with cytomegalovirus infection. We undertook a systematic review to investigate whether this approach affects risks of cytomegalovirus disease and death.
Methods: Randomised controlled trials of prophylaxis with antiviral medications for cytomegalovirus disease in solid-organ-transplant recipients were identified. Data were combined in meta-analyses by a random-effects model.
Findings: Compared with placebo or no treatment, prophylaxis with aciclovir, ganciclovir, or valaciclovir significantly reduced the risks of cytomegalovirus disease (19 trials, 1981 patients; relative risk 0.42 [95% CI 0.34-0.52]), cytomegalovirus infection (17 trials, 1786 patients; 0.61 [0.48-0.77]), and all-cause mortality (17 trials, 1838 patients; 0.63 [0.43-0.92]), mainly owing to lower mortality from cytomegalovirus disease (seven trials, 1300 patients; 0.26 [0.08-0.78]). Prophylaxis also lowered the risks of disease caused by herpes simplex or zoster virus, bacterial infections, and protozoal infections, but not fungal infection, acute rejection, or graft loss. Meta-regression showed no significant difference in the risk of cytomegalovirus disease or all-cause mortality by organ transplanted or cytomegalovirus serostatus; no conclusions were possible for cytomegalovirus-negative recipients of negative organs. In trials of direct comparisons, ganciclovir was more effective than aciclovir in preventing cytomegalovirus disease. Valganciclovir and intravenous ganciclovir were as effective as oral ganciclovir.
Interpretation: Prophylaxis with antiviral medications reduces the risk of cytomegalovirus disease and associated mortality in recipients of solid-organ transplants. This approach should be used routinely in cytomegalovirus-positive recipients and in cytomegalovirus-negative recipients of organs positive for the virus.