Sirolimus, being nonnephrotoxic, is a viable alternative in patients who develop
renal insufficiency caused by
calcineurin inhibitors (CIs). The aim of this study is to determine whether there is improvement in renal function in
liver transplant recipients after switching to
sirolimus-based immunosuppression. In this retrospective review, patients who were more than 3 years posttransplantation were selected. Patients who had
proteinuria (
protein > 300 mg/24 hr), those administered any other nephrotoxic agents, and those with a
creatinine clearance (CCr) less than 20 mL/min were excluded.
Renal insufficiency was defined as mild (CCr > 70 mL/min), moderate (CCr, 40 to 70 mL/min), or severe (CCr, 20 to 40 mL/min). In the 16 patients studied; there was significant improvement in serum blood
urea nitrogen (36 mg/dL; range, 19 to 53 mg/dL; to 25 mg/dL; range, 10 to 37 mg/dL; P =.002) and serum
creatinine levels (median, 1.95 mg/dL; range, 1.3 to 2.8 mg/dL; to 1.5 mg/dL; range, 1.0 to 2.4 mg/dL; P =.001) 6 months after switching to
sirolimus therapy. There also was a trend in improvement in CCr from 43 mL min (range, 24 to 68 mL/min) to 49 mL/min (range, 22 to 152 mL/min). Among 9 patients with moderate
renal insufficiency, 2 patients improved to mild
renal insufficiency, 4 patients remained unchanged, and 3 patients deteriorated to severe
renal insufficiency. Among 7 patients with severe
renal insufficiency, 1 patient improved to mild
renal insufficiency, 4 patients improved to moderate
renal insufficiency, and 2 patients remained unchanged. No patient developed cellular rejection or other graft-related complications. In
liver transplant recipients with
chronic renal insufficiency, conversion to
sirolimus-based immunosuppression allows complete withdrawal of CIs, leading to some improvement in renal function.