Conversion from cyclosporin to azathioprine in renal allograft recipients

Renal function in five patients who were on a combination of Cyclosporin A (CyA) and Prednisone for 2-6 years following renal transplantation, were evaluated, in order to consider change from CyA-prednisone combination to conventional therapy. (Azathioprine-prednisone combination). This was necessitated by CyA nephrotoxicity, its high cost and unreliable monitoring. The maintenance dose of CyA ranged between 200 and 400 mg per day. The BUN levels during CyA treatment ranged from 6 to 15 mmol/l (normal 3.7-6.7 mmol/l), and plasma creatinine from 200 to 300 Umol/l (normal 67-107 Umol/l). The serum electrolytes were normal. The urine outputs were normal. Rejections were treated by pulses of one gram of methyl-prednisolone daily for 3 days. Maintenance prednisolone ranged from 10-15 mg per day. After tapering off the CyA and eventually stopping it, Azathioprine 100-150 mg daily with prednisolone 10-15 mg per day were instituted. There were significant drops in creatinine and BUN levels after the change over, with general well being and good urinary outputs. The patients refused consent for renal biopsy to prove CyA histologic toxicity.