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Can the nephron be spared?

Stuart M Flechner1

  • 1Cleveland Clinic Lerner College of Medicine, Glickman Urological and Kidney Institute, Cleveland, Ohio 44195, USA. flechns@ccf.org

Kidney International
|April 1, 2011
PubMed

Insights

The Spare the Nephron Trial found early conversion to sirolimus improved kidney function after transplantation compared to calcineurin inhibitors (CNIs). Some patients experienced sirolimus tolerability issues.

Area of Science:

  • Nephrology
  • Immunosuppression
  • Transplantation medicine

Background:

  • Calcineurin inhibitors (CNIs) are standard immunosuppressants in renal transplantation but cause nephrotoxicity.
  • Mammalian target of rapamycin (mTOR) inhibitors offer an alternative immunosuppressive strategy.
  • Minimizing CNI-induced nephrotoxicity is crucial for long-term graft survival.

Purpose of the Study:

  • To evaluate the efficacy and safety of early conversion from CNIs to an mTOR inhibitor (sirolimus) in renal transplant recipients.
  • To assess the impact of this conversion strategy on renal function and graft outcomes.

Main Methods:

  • The Spare the Nephron Trial involved patients maintained on mycophenolate mofetil and steroids.
  • Participants underwent early conversion from CNIs to sirolimus.
  • Renal function, assessed by glomerular filtration rate (GFR), was monitored over 1-2 years.

Main Results:

  • Patients converted to sirolimus demonstrated superior glomerular filtration rates (GFR) at 1-2 years post-transplantation.
  • Approximately 20% of patients experienced a loss of tolerability to sirolimus.
  • The study highlights a trade-off between improved renal function and potential adverse effects.

Conclusions:

  • Early conversion to sirolimus can improve renal function in renal transplant recipients.
  • Sirolimus represents a viable alternative to CNIs for minimizing nephrotoxicity.
  • Careful patient selection and monitoring are necessary due to potential tolerability issues with sirolimus.

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