Pancreas Kidney Transplantation (PKT) is the prominent treatment for type 1 diabetic patients with chronic kidney disease and improves patients' outcome. However, in spite of an optimized systemic insulin substitution, altered glucose metabolism and beta cell function are reported in these patients. The mechanisms behind these abnormalities are still unclear. Duodena-pancreatic anastomosis is performed in a heterotopic site (ileum) and thus could change physical and chemical properties of intestinal secretions, gut flora, as well as intestinal permeability. The effect of this procedure on gut derived metabolic factors, the enterohepatic cycle of bile acids, incretin secretion and intestinal flora have never been studied. This pilot prospective, study is aimed to evaluate the modification of bile acids concentrations and composition in PKT subjects, and the impact in glucose and incretin metabolism (measured by oral glucose tolerance test) one year after transplantation. The results will be compared to those of kidney transplant patients and control subjects.