Diagnosis of patients with renal insufficiency and recommendations for medical treatment of patients who suffer from chronic renal failure are based on the different stages of Glomerular Filtration Rate (GFR). Many formulas exist to assess GFR. However these formulas are unreliable in many clinical situations (old people, obese patients…). Methods for measuring GFR using exogenous tracers exist: Inulin and 51Cr-EDTA are historical reference tracers. Renal clearance of Inulin is the gold standard. However, using these methods is restricted to specialized services because it is long and expensive.

There is no medical data for the use of Calcium edetate de sodium as a tracer to assess GFR. Calcium edetate de sodium is a treatment for lead intoxication. The extension of use as a tracer comes from its exclusive elimination by glomerular filtration.

Plasma and renal clearance of Calcium edetate de sodium and Inulin will be measured for every included patient during a hospital day care (First visit V1). For transplanted patients, plasma clearance of Calcium edetate de sodium will be repeated within one week (more or less 48hours) during annual medical check-up of renal transplantation (Second visit V2).

Inclusion Criteria:

• Inclusion criteria for V1:
• For transplanted patients : patients from 18 to 80 years, after estimation of their renal function by MDRDs formulas (MDRD = Modification of Diet in Renal Disease) , regardless their nephropathy, regardless the age of the transplantation, with a normal state body hydratation, with a social insurance and who have given their prior consent.
• For other patients : patients from 18 to 80 years, after estimation of their renal function by MDRDs formulas, who need a reliable assess of their renal function, with a normal state body hydratation, with a social insurance and who have given their prior consent.
• Inclusion criteria for V2: Transplanted patients who have participated to V1, with stable clinical conditions, with a stable GFR (less than 30% variation of creatinine clearance by MDRDs formulas) and who have given their prior consent.

Exclusion Criteria:

• Hypersensitivity to Calcium edetate de sodium
• Inulin or excipients
• Lead or other heavy metal intoxication
• Volume expansion or dehydration
• Acute renal disease
• Bladder voiding affections
• Coagulation disorders
• Poor venous capital
• People in guardianship
• Patients already involved in an other research
• Women in child bearing age without any method of contraception
• Pregnant or lactating women.