Decreased incidence of acute rejection without increased incidence of cytomegalovirus (CMV) infection in kidney transplant recipients receiving rabbit anti-thymocyte globulin without CMV prophylaxis - a cohort single-center study

Abstract

Induction therapy with rabbit anti-thymocyte globulin (rATG) in low-risk kidney transplant recipients (KTR) remains controversial, given the associated increased risk of cytomegalovirus (CMV) infection. This natural experiment compared 12-month clinical outcomes in low-risk KTR without CMV prophylaxis (January/3/13-September/16/15) receiving no induction or a single 3 mg/kg dose of rATG. We used logistic regression to characterize delayed graft function (DGF), negative binomial to characterize length of hospital stay (LOS), and Cox regression to characterize acute rejection (AR), CMV infection, graft loss, death, and hospital readmissions. Recipients receiving 3 mg/kg rATG had an 81% lower risk of AR (aHR _0.14 0.19_0.25 , P < 0.001) but no increased rate of hospital readmissions because of infections (_0.68 0.91_1.21 , P = 0.5). There was no association between 3 mg/kg rATG and CMV infection/disease (aHR _0.86 1.10_1.40 , P = 0.5), even when the analysis was stratified according to recipient CMV serostatus positive (aHR _0.94 1.25_1.65 , P = 0.1) and negative (aHR _0.28 0.57_1.16 , P = 0.1). There was no association between 3 mg/kg rATG and mortality (aHR _0.51 1.25_3.08 , P = 0.6), and graft loss (aHR _0.34 0.73_1.55 , P = 0.4). Among low-risk KTR receiving no CMV pharmacological prophylaxis, 3 mg/kg rATG induction was associated with a significant reduction in the incidence of AR without an increased risk of CMV infection, regardless of recipient pretransplant CMV serostatus.

Keywords: CMV infection; acute rejection; low immunological risk; thymoglobulin.