title: Urinary renalase concentration in patients with preserved kidney function undergoing coronary angiography.
abstract: OBJECTIVE
  The purpose of the study was to evaluate urinary renalase concentration before and after coronary angiography/percutaneous coronary interventions (CA/PCI) in patients with coronary artery disease (CAD) and preserved kidney function and verify its potential application as contrast-induced acute kidney injury (CI-AKI) diagnostic marker.
  
  
  METHODS
  This prospective study comprised 95 consecutive patients (69.5% men; median age 65 years) with CAD submitted to elective or urgent CA/PCI. Data regarding 128 clinical variables were obtained. Urine samples were collected on admission and 6 h after CA/PCI and tested for urinary renalase using ELISA method, which was expressed as renalase-to-creatinine ratio. The CI-AKI diagnosis was based on ≥50% relative or ≥0.3 mg/dl absolute increase of serum creatinine concentration 48 h following the procedure.
  
  
  RESULTS
  Nine patients developed CI-AKI (9.5%). In comparison to baseline values, urinary renalase-to-creatinine ratio significantly decreased 6 h following CA/PCI, (2843.6 vs.1540.7 ng/mg, P < 0.0001). Nine patients developed CI-AKI (9.5%).The reduction of renalase level was profound both in CI-AKI (2709.7 vs. 1585.7 ng/mg, P = 0.007) and non-CI-AKI group (2814.9 vs.1561.8 ng/mg, P < 0.0001). There was a trend towards a greater relative decrease of urinary renalase in CI-AKI group (-57.3 vs.-41.8%, P = 0.10). Univariate analysis revealed that both pre- and post-procedural urinary renalase did not predict CI-AKI onset; however, absolute decrease of renalase below 25 percentile was a predictor of CI-AKI (OR = 5.4, 95% CI:1.3-21.9, P = 0.027).
  
  
  CONCLUSIONS
  Urinary renalase concentration is reduced in the aftermath of CA/PCI, which may be related to CI-AKI development. Further studies are warranted to elucidate the role of urinary renalase as a CI-AKI diagnostic marker.
authors: First Department of Cardiology, School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland.
authors: Maciej T
authors: MT
authors: Wybraniec
authors: Department of Pathophysiology, Medical University of Silesia, Katowice, Poland.
authors: Maria
authors: M
authors: Bożentowicz-Wikarek
authors: Department of Pathophysiology, Medical University of Silesia, Katowice, Poland.
authors: Jerzy
authors: J
authors: Chudek
authors: First Department of Cardiology, School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland.
authors: Katarzyna
authors: K
authors: Mizia-Stec
mesh_terms: D058186:Acute Kidney Injury / Q000139:chemically induced* / Q000175:diagnosis / Q000652:urine*; D000368:Aged; D019540:Area Under Curve; D015415:Biomarkers / Q000652:urine; D003287:Contrast Media / Q000009:adverse effects*; D017023:Coronary Angiography / Q000009:adverse effects*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000628:therapy* / Q000652:urine; D003404:Creatinine / Q000652:urine; D042241:Early Diagnosis; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D008995:Monoamine Oxidase / Q000652:urine*; D015999:Multivariate Analysis; D016017:Odds Ratio; D062645:Percutaneous Coronary Intervention / Q000009:adverse effects*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012372:ROC Curve; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D003287:Contrast Media; D003404:Creatinine; D008995:Monoamine Oxidase; C521557:renalase
keywords: contrast-induced acute kidney injury; renalase; urinary markers