title: Outcomes after simultaneous pancreas and kidney transplantation and the discriminative ability of the C-peptide measurement pretransplant among type 1 and type 2 diabetes mellitus.
abstract: BACKGROUND
  Earlier studies reporting outcomes after pancreas transplantation have included a combination of C-peptide cutoffs and clinical criteria to classify type 2 diabetes mellitus (T2DM). However, because the kidney is the major site for C-peptide catabolism, C-peptide is unreliable to discriminate the type of diabetes in patients with kidney disease.
  
  
  METHODS
  To improve the discriminative power and better classify the type of diabetes, we used a composite definition to identify T2DM: presence of C-peptide, negative glutamic acid decarboxylase antibody, absence of diabetic ketoacidosis, and use of oral hypoglycemics. Additionally among T2DM patients with end-stage renal disease (ESRD), body mass index of <30 kg/m(2) and use of <1 u/kg of insulin per day were selection criteria for suitablity for simultaneous pancreas and kidney transplantation (SPKT). We compared graft and patient survival between T1DM and T2DM after SPKT.
  
  
  RESULTS
  Our study cohort consisted of 80 patients, 10 of whom were assigned as T2DM based on our study criteria. Approximately 15% of patients with T1DM had detectable C-peptide. Cox regression survival analyses found no significant differences in allograft (pancreas and kidney) or patient survival between the 2 groups. The mean creatinine clearance at 1 year estimated by the modification of Diet in Renal Disease (MDRD) equation was not significantly different between the 2 groups. Among those with 1 year of follow-up, all patients with T2DM had glycosylate hemoglobin of <6.0 at 1 year versus 92% of those with T1DM.
  
  
  CONCLUSIONS
  SPKT should be considered in the therapeutic armamentarium for renal replacement in selected patients with T2DM and ESRD. Use of C-peptide measurements for ESRD patients can be misleading as the sole criterion to determine the type of diabetes.
authors.affiliation: Mayo Clinic, Scottsdale, Arizona, USA. chakkera.harini@mayo.edu
authors.forename: H A
authors.initials: HA
authors.lastname: Chakkera
authors.forename: J K
authors.initials: JK
authors.lastname: Bodner
authors.forename: R L
authors.initials: RL
authors.lastname: Heilman
authors.forename: D C
authors.initials: DC
authors.lastname: Mulligan
authors.forename: A A
authors.initials: AA
authors.lastname: Moss
authors.forename: K L
authors.initials: KL
authors.lastname: Mekeel
authors.forename: M J
authors.initials: MJ
authors.lastname: Mazur
authors.forename: K
authors.initials: K
authors.lastname: Hamawi
authors.forename: R M
authors.initials: RM
authors.lastname: Ray
authors.forename: G L
authors.initials: GL
authors.lastname: Beck
authors.forename: K S
authors.initials: KS
authors.lastname: Reddy
mesh_terms: D000328:Adult; D002096:C-Peptide / Q000097:blood*; D003404:Creatinine / Q000097:blood; D003922:Diabetes Mellitus, Type 1 / Q000601:surgery*; D003924:Diabetes Mellitus, Type 2 / Q000601:surgery*; D003928:Diabetic Nephropathies / Q000453:epidemiology / Q000601:surgery*; D003930:Diabetic Retinopathy / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D006442:Glycated Hemoglobin / Q000032:analysis; D006084:Graft Rejection / Q000453:epidemiology; D006801:Humans; D007676:Kidney Failure, Chronic / Q000601:surgery*; D016030:Kidney Transplantation / Q000276:immunology / Q000401:mortality / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D016035:Pancreas Transplantation / Q000276:immunology / Q000401:mortality / Q000502:physiology*; D012189:Retrospective Studies; D016019:Survival Analysis; D014019:Tissue Donors / Q000706:statistics & numerical data
chemical_list: D002096:C-Peptide; D003404:Creatinine; D006442:Glycated Hemoglobin