title: Urinary ET-1 excretion after exposure to radio-contrast media in diabetic patients and patients with preexisting mild impaired renal function.
abstract: OBJECTIVE
  Contrast media-induced nephropathy (CIN) is associated with increased morbidity and mortality. The renal endothelin system has been associated with disease progression of various acute and chronic renal diseases. However, robust data coming from adequately powered prospective clinical studies analyzing the short and long-term impacts of the renal ET system in patients with CIN are missing so far. We thus performed a prospective study addressing this topic.
  
  
  METHODS
  We included 327 patients with diabetes or renal impairment undergoing coronary angiography. Blood and spot urine were collected before and 24 h after contrast media (CM) application. Patients were followed for 90 days for major clinical events like need for dialysis, unplanned rehospitalization or death.
  
  
  RESULTS
  The concentration of ET-1 and the urinary ET-1/creatinine ratio decreased in spot urine after CM application (ET-1 concentration: 0.91±1.23 pg/ml versus 0.63±1.03 pg/ml, p<0.001; ET-1/creatinine ratio: 0.14±0.23 versus 0.09±0.19, p<0.001). The urinary ET-1 concentrations in patients with CIN decreased significantly more than in patients without CIN (-0.26±1.42 pg/ml vs. -0.79±1.69 pg/ml, p=0.041), whereas the decrease of the urinary ET-1/creatinine ratio was not significantly different (non-CIN patients: -0.05±0.30; CIN patients: -0.11±0.21, p=0.223). Urinary ET-1 concentrations as well as the urinary ET-1/creatinine ratio were not associated with clinical events (need for dialysis, rehospitalization or death) during the 90 day follow-up after contrast media exposure. However, the urinary ET-1 concentration and the urinary ET-1/creatinine ratio after CM application were higher in those patients who had a decrease of GFR of at least 25% after 90 days of follow-up.
  
  
  CONCLUSIONS
  In general the ET-1 system in the kidney seems to be down-regulated after contrast media application in patients with moderate CIN risk. Major long-term complications of CIN (need for dialysis, rehospitalization or death) are not associated with the renal ET system.
authors.affiliation: Center for Cardiovascular Research, Charité, Berlin, Germany.
authors.forename: Fabian
authors.initials: F
authors.lastname: Heunisch
authors.affiliation: Center for Cardiovascular Research, Charité, Berlin, Germany.
authors.forename: Gina
authors.initials: G
authors.lastname: von Einem
authors.affiliation: Center for Cardiovascular Research, Charité, Berlin, Germany; Department of Nephrology, Campus Benjamin Franklin, Charité, Berlin, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Alter
authors.affiliation: Center for Cardiovascular Research, Charité, Berlin, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Weist
authors.affiliation: Immundiagnostik AG, Bensheim, Germany; Department of Cardiology and Angiology, Charité Campus Mitte, Berlin, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Dschietzig
authors.affiliation: Bayer Pharma AG, Wuppertal, Germany.
authors.forename: Axel
authors.initials: A
authors.lastname: Kretschmer
authors.affiliation: Institute for Nutritional Science, University of Potsdam, Potsdam, Germany. Electronic address: hocher@uni-potsdam.de.
authors.forename: Berthold
authors.initials: B
authors.lastname: Hocher
mesh_terms: D000368:Aged; D015331:Cohort Studies; D003287:Contrast Media / Q000009:adverse effects*; D003404:Creatinine / Q000652:urine; D003920:Diabetes Mellitus / Q000503:physiopathology* / Q000652:urine*; D019332:Endothelin-1 / Q000652:urine*; D005260:Female; D006801:Humans; D007677:Kidney Function Tests; D008297:Male; D019275:Radiopharmaceuticals / Q000009:adverse effects*
chemical_list: D003287:Contrast Media; D019332:Endothelin-1; D019275:Radiopharmaceuticals; D003404:Creatinine
keywords: Clinical study; Kidney; Radiocontrast media-induced nephropathy; Urinary ET-1