Effect of mammalian target of rapamycin inhibitors on cytomegalovirus infection in kidney transplant recipients receiving polyclonal antilymphocyte globulins: a propensity score‐matching analysis

Summary Mammalian target of rapamycin inhibitors ( mTOR i) prevents cytomegalovirus ( CMV ) infection in kidney transplant ( KT ) patients. From May 2010 to December 2013, all KT recipients were retrospectively analysed. Maintenance immunosuppression regimen was divided into mTOR i or calcineurin inhibitors ( CNI )‐based regimen. Since June 2011, CMV ‐seropositive recipients (R+) treated with high‐intensity immunosuppression and mTOR i did not receive anti‐ CMV prophylaxis. We analysed 350 consecutive patients, of which 95 (27%) received mTOR i and 255 (73%) CNI ‐based immunosuppression. A Cox‐regression multivariate analysis showed that the use of mTOR i‐based immunosuppression during all follow‐up reduced the risk of CMV infection ( HR 0.36, 95% CI 0.15–0.89, P = 0.028) and confirmed in a propensity score‐matched cohort ( HR 0.4, 95% CI 0.1–0.9, P = 0.047). Early discontinuation of mTOR i increased the risk of CMV infection ( HR 3.2; 95% CI 1.7–6.0) in univariate analysis. The incidence of CMV infection was not higher among CMV R+ patients on mTOR i and requiring high‐intensity immunosuppression when CMV prophylaxis was not given. The use of mTOR i protected for CMV infection in KT patients, allowing to avoid antiviral prophylaxis for R+ patients receiving high‐intensity immunosuppression. The increased risk of CMV infection after early discontinuation of mTOR i warrants further research.