The Risk Factors of mTORi-Associated Posttransplant Proteinuria.

Treatment with mammalian target of rapamycin inhibitors (mTORi) has been associated with an increased incidence of proteinuria after kidney transplantation as compared to other immunosuppressive agents. Proteinuria after mTORi use may occur in different clinical conditions and the precise mechanism remains unclear. The objective of this study was to investigate the related risk factors for proteinuria after mTORi treatment in kidney transplant recipients. This retrospective observational study population consisted of kidney transplant recipients followed up in a medical center in Southern Taiwan from January 1999 to April 2016. The baseline characteristics and transplantation-related profiles were collected at the time of enrollment. We examined risk factors for mTORi-associated proteinuria using a multivariate logistic regression analysis. P < .05 was considered as statistically significant. Hyperlipidemia and obesity at the initiation of mTORi treatment were strong predictors for proteinuria. Earlier identification of these risk factors may assist physicians in deciding the best candidate for mTORi conversion in order to optimize transplantation outcomes.

Risk Factors Associated With Mammalian Target of Rapamycin Inhibitor Withdrawal in Kidney Transplant Recipients.

BACKGROUND: Mammalian target of rapamycin inhibitors (mTORi) play an essential role as novel immunosuppressive agents in kidney transplantation (KT). Treatment cessation usually occurs after adverse effects occur. We investigated the risk factors associated with withdrawal of mTORi in KT recipients and evaluated the outcomes related to the withdrawal. METHODS: The study enrolled KT recipients being followed up in a medical center in southern Taiwan from January 1999 through December 2014. RESULTS: Risk factors associated with mTORi withdrawal were initial proteinuria level, higher initial serum creatinine level posttransplantation, and history of glomerulonephritis as the primary etiology of renal failure. mTORi withdrawal was associated with increased risk of graft failure (hazard ratio [HR], 9.97 [95% confidence interval (CI), 1.03-96.8]; P = .047). Higher body mass index (HR, 11.2 [95% CI, 1.63-76.6]; P = .01) and tacrolimus usage (HR, 8.30 [95% CI, 1.14-60.7]; P = .037) were associated with increased risk of new-onset diabetes after transplantation in mTORi withdrawal groups. CONCLUSIONS: Proteinuria, poor graft function, and primary glomerulonephritis were associated with cessation of mTORi treatment. Earlier identification of these risk factors may prevent further adverse events and optimize transplantation outcomes after mTORi conversion.