Assessment of glomerular and tubular functions in renal transplant patients receiving cyclosporine A in combination with either sirolimus or everolimus.
OBJECTIVE
The aim of this study was to examine the glomerular filtration rate (GFR) and tubular function at three months after renal transplantation in two groups of patients receiving cyclosporine A associated with either sirolimus (SRL) (n = 18) or everolimus (RAD) (n = 12), two structurally similar immunosuppressant drugs.


RESULTS
Donors' and recipients' characteristics and mean cyclosporine A trough levels were similar in the two groups. The mean sirolimus trough level was 12.01 +/- 1.6 ng/ml whereas the mean everolimus trough level was 4.23 +/- 0.36 ng/ml. GFR, equated by the clearance of inulin, was higher in RAD patients (64 +/- 4 ml. min- 1.1.73 m(-2)) than in SRL patients (49 +/- 4 ml.min(-1) .1.73 m(-2)) (p < 0.05). The significant difference in GFR between the groups was not affected by differences in mean arterial blood pressures, or by differences in daily prednisone dosages, cyclosporine trough levels, or SRL and RAD trough levels. Phosphatemia, renal phosphate threshold (TmPO4/ GFR ratio) and uric acid clearance were significantly lower in the SRL than in the RAD group, despite similar levels of parathyroid hormone. Finally, urinary acid excretion was significantly lower in the RAD group.


CONCLUSIONS
In conclusion, regarding nephrotoxicity, our preliminary data suggest that it seems to be preferable to combine cyclosporine with RAD rather than with sirolimus in renal transplant patients. However, long-term renal effects of this combination are still to be determined in a larger cohort.
Kamar
N
N
Department of Nephrology, Dialysis and Transplantation, CHU Rangueil, Toulouse Cedex, France. kamar.n@chu-toulouse.fr
Allard
J
J
Ribes
D
D
Durand
D
D
Ader
J L
JL
Rostaing
L
L
D000328:Adult; D016572:Cyclosporine / Q000008:administration & dosage*; D004359:Drug Therapy, Combination; D000068338:Everolimus; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate / Q000187:drug effects*; D005938:Glucocorticoids / Q000008:administration & dosage; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage*; D016030:Kidney Transplantation; D007684:Kidney Tubules / Q000187:drug effects* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011241:Prednisone / Q000008:administration & dosage; D020123:Sirolimus / Q000008:administration & dosage* / Q000031:analogs & derivatives*; D013997:Time Factors
D005938:Glucocorticoids; D007166:Immunosuppressive Agents; D016572:Cyclosporine; D000068338:Everolimus; D011241:Prednisone; D020123:Sirolimus