title: Serum uric acid may predict development of progressive acute kidney injury after open heart surgery.
abstract: OBJECTIVE
  Acute kidney injury (AKI) is a common complication of cardiac surgery developing in 25-35% cases. Recently, neutrophil gelatinase-associated lipocalin (NGAL) was shown to predict AKI development earlier than serum creatinine. Some studies demonstrated the predictive role of post-operative serum uric acid (SUA) as an early marker of AKI. We aimed to study the role of serum and urine NGAL as well as SUA to predict progression of AKI.
  
  
  METHODS
  This is a prospective observational study of patients undergoing cardiac surgery. Blood and urine samples for measurement of uric acid, serum and urine NGAL levels were collected prior to cardiac surgery (0 h), and in the time course at 2nd and 24th hours after surgery. Patients who developed AKI were divided into two subgroups as progressing and non-progressing AKI.
  
  
  RESULTS
  Sixty patients (42 males, 18 females) were included. After cardiac surgery, 40 patients developed AKI, 20 of whom non-progressing AKI, and 20 progressing AKI. All of the markers significantly increased in AKI patients. A receiver operator characteristics (ROC) curve analysis showed higher predictive ability of SUA for progressing AKI compared with serum and urine NGAL. When compared markers obtained at the second hour after surgery, UA had significantly large AUC than NGAL to predict AKI developed at 24 and 48 h, particularly in patients, who require renal replacement therapy (RRT).
  
  
  CONCLUSIONS
  Uric acid seems to predict the progression of AKI and RRT requirement in patients underwent cardiac surgery better than NGAL.
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Meram School of Medicine, Necmettin Erbakan University , Konya , Turkey .
authors.forename: Abduzhappar
authors.initials: A
authors.lastname: Gaipov
authors.forename: Yalcin
authors.initials: Y
authors.lastname: Solak
authors.forename: Kultigin
authors.initials: K
authors.lastname: Turkmen
authors.forename: Aysun
authors.initials: A
authors.lastname: Toker
authors.forename: Ahmet Nihat
authors.initials: AN
authors.lastname: Baysal
authors.forename: Humeyra
authors.initials: H
authors.lastname: Cicekler
authors.forename: Zeynep
authors.initials: Z
authors.lastname: Biyik
authors.forename: Fatih Mehmet
authors.initials: FM
authors.lastname: Erdur
authors.forename: Alper
authors.initials: A
authors.lastname: Kilicaslan
authors.forename: Melih
authors.initials: M
authors.lastname: Anil
authors.forename: Niyazi
authors.initials: N
authors.lastname: Gormus
authors.forename: Halil Zeki
authors.initials: HZ
authors.lastname: Tonbul
authors.forename: Mehdi
authors.initials: M
authors.lastname: Yeksan
authors.forename: Suleyman
authors.initials: S
authors.lastname: Turk
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D000209:Acute-Phase Proteins; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D018450:Disease Progression; D005260:Female; D006801:Humans; D000071068:Lipocalin-2; D054834:Lipocalins / Q000097:blood; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000097:blood / Q000175:diagnosis / Q000503:physiopathology; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D011518:Proto-Oncogene Proteins / Q000097:blood; D014421:Turkey; D014527:Uric Acid / Q000097:blood*
chemical_list: D000209:Acute-Phase Proteins; D015415:Biomarkers; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D011518:Proto-Oncogene Proteins; D014527:Uric Acid
keywords: Acute kidney injury; cardiac surgery; neutrophil gelatinase-associated lipocalin; uric acid