NO EFFECT OF CYCLOSPORINE WITHDRAWAL ON GLUCOSE-METABOLISM AT ONE-YEAR AFTER KIDNEY-TRANSPLANTATION

The negative effect of cyclosporine A on glucose tolerance has been demonstrated in vitro, in experimental animals and in man and a higher incidence of post-transplant diabetes mellitus has been reported in cyclosporine-treated kidney recipients by several authors, The aim of the present study was to establish whether elective cyclosporine A withdrawal at one year after kidney transplantation causes any changes in glucose tolerance, insulin secretion and insulin action, Metabolic investigations using hyperglycemic (12 mmol/l for 120 min) and hyperinsulinemic euglycemic (insulin infusion rates of 1.0 and 10.0 mU/kg.min) techniques were performed in 9 non-diabetic kidney recipients on a triple immunosuppressive regimen (cyclosporine A, prednisone and azathioprine) and 8-24 weeks later after cyclosporine A withdrawal. The differences between the data before and after cyclosporine withdrawal were tested by Wilcoxon's pair test, No statistical differences (p>0.05) were observed in fasting glucose levels? glycosylated hemoglobin, first- and second-phase insulin and C-peptide secretion (assessed during the hyperglycemic clamp) and intravenous glucose tolerance (assessed using the hyperglycemic clamp technique). The hyperinsulinemic clamp examination did not reveal any significant changes in insulin action either at physiological or at pharmacological insulin levels, Thus we conclude that cyclosporine A withdrawal in chronically immunosuppressed kidney recipients does not cause any significant changes in glucose metabolism and probably does not help prevent post-transplant diabetes mellitus.