Background: To overcome toxicity of calcineurin inhibitors, recent trials have proposed substituting cyclosporin (CysA) with mycophenolate mofetil (MMF). No data concerning the long-term side effects and long-term renal outcome of this strategy have been published.
Methods: We retrospectively compared 39 renal transplant patients with chronic graft dysfunction who were subjected to CysA to MMF substitution (group 1) with 39 matched renal transplant patients who were continued on conventional management (group 2). The mean serum creatinine and the slope of deterioration of renal function before the date of the therapeutic intervention (T(0)) were similar in both groups. Follow-up in both groups was 76 +/- 42 months before T(0) and 44 +/- 11 months after T(0).
Results: In group 1, conversion was associated with a decrease of mean serum creatinine concentrations from 192 to 172 micro mol/l at 1 year (P = 0.004) and 159 micro mol/l at 3 years (P < 0.003) after T(0), whereas it remained unchanged in group 2. The systolic blood pressure decreased in group 1 from 155 mmHg before T(0) to 145 mmHg at 1 year (P < 0.01) and 133 mmHg at 3 years (P < 0.001) without any increase of the antihypertensive drug, whereas it did not change in group 2. Lipid profile tended to improve in group 1 after T(0) and was unchanged in group 2. None of the patients in group 1 developed acute rejection after T(0), whereas two acute rejections occurred in group 2. Graft survival, however, was similar in both groups. In group 1, several side effects occurred related to MMF treatment, and led to its discontinuation in two cases and the reduction of its dose for 18 patients (64%).
Conclusion: CysA/MMF substitution improves renal function and blood pressure in chronic allograft dysfunction when compared with conventional management. However, CysA/MMF substitution is associated with a high rate of MMF-related side effects, requiring modulation of its dose.