EVIDENCE THAT ADDITION OF AZATHIOPRINE IMPROVES RENAL-FUNCTION IN CYCLOSPORINE-TREATED PATIENTS WITH ALLOGRAFT DYSFUNCTION

Several approaches have been attempted to manage renal allograft dysfunction in cyclosporine-prednisone (CsA-Pred)-treated patients. Conversion to conventional therapy and perioperative triple drug have been associated with high rates of acute rejection episodes, infections, or neoplasms. We report our experience in delayed addition of azathioprine (1-2 mg/kg/day) to CsA/Pred protocol in three groups of patients. Group I (n = 9) had chronic renal function deterioration due to chronic rejection; group II (n = 10) had repeated or severe acute rejection episodes despite adequate CsA levels; and group III (n = 8) had CsA toxicity despite drug tapering. In group I, serum creatinine (SCr) had risen from 2.2 +/- 0.9 to 2.9 +/- 0.7 mg/dl over the 6 months prior to Aza addition (P < 0.05), renal function declining at a rate of -0.14 +/- 0.12 Cr-1/year. In the 6-month post-Aza, renal function improved at a rate of 0.06 +/- 0.06 Cr-1/ year and during the entire follow-up at a rate of 0.04 +/-0.12 Cr-1/year (P < 0.05) with stable CsA levels (288 +/-167 vs. 251 +/- 172 ng/dl, NS). In group II response was worse, though the rate of declining renal function prior to Aza (-0.10 +/- 0.10 Cr-1/year) was almost stopped after Aza. In group III there was very good response to Aza addition, as 7 out of 8 patients improved graft function (baseline SCr 2.5 +/- 0.7 mg/dl vs. 1.9 +/- 0.6 mg/dl at last follow-up, P < 0.05), with significantly decreased CsA levels (480 +/- 97 vs. 268 +/- 120, P < 0.05). One patient from group 11 died from pneumonia, and 6 patients (I from group I and 5 from group II) lost their grafts. Fifteen patients improved graft function, and 9 worsened after addition of Aza. The bad-responders had significantly higher SCr at baseline compared with the good-responders (3.8 +/- 1.8 vs. 2.7 +/- 0.6 mg/dl, P <0.01). Amelioration of chronic graft dysfunction can be achieved by delayed addition of Aza to CsA-Pred in patients with chronic rejection or CsA toxicity. This is accompanied by low rate of acute rejection, good patient and graft survival, and low rate of infections. A worse outcome can be seen in patients with high-baseline SCr levels, suggesting the need for addition of Aza in the initial chronic graft dysfunction.