Introduction: The use of everolimus (EVE) with tacrolimus (TAC) minimization in renal transplantation is safe and effective in preventing rejection. Postransplant detection of donor specific antibodies (DSA) has been associated with an increased risk of developing rejection and leads to worse graft survival.
The aim of our study was to describe the effect of the conversion from mycophenolate mofetil (MMF) with standard exposure TAC to EVE with TAC minimization in stable kidney transplanted recipients, on DSA development.
Methods: We studied 229 kidney transplants performed consecutively from 07/01/2011 to 12/31/2016. 57 (24,89%) kidney recipients converted from MMF to EVE with TAC minimization was performed. The recipients had stable renal function and no proteinuria. DSA were assessed  before transplantation, quarterly during the first year after transplantation, before conversion and at the end of the study.
Results: Of the 57 patients, 64.9% were male. The mean age was 57.19 ± 15.52 years. The median time from transplant to conversion was 6 months (IQR 2.25-13). The conversion was due to: viral infection 25 (44%), neoplasia 11 (19.3%), nephrotoxicity induced by calcineurin inhibitors 2 (3.5%), indication of the clinician 15 (26.3%) and diarrhea 4 (7%). 7,7% of patients had DSA and 3,5% MICA antibodies before transplantation. We observed a decrease in DSA and MICA antibodies from 6 patients (11.8%) and 2 (3.9%) before conversion to 3 patients (6%) and 0 at the end of the study, respectively. No patient presented acute rejection after conversion. Renal function remained stable, with increased proteinuria at the end of the study.
Conclusions: In our experience, conversion to EVE allows TAC minimization without increasing DSA production.