Post-operative serum uric acid and acute kidney injury

J Nephrol. Jul-Aug 2012;25(4):497-505. doi: 10.5301/jn.5000173.

Abstract

Background: We hypothesized that post-operative serum uric acid (SUA) may be associated with acute kidney injury (AKI).

Methods: In this prospective, observational study, the relationships between SUA, urine neutrophil gelatinase-associated lipocalin (uNGAL) and interleukin-18 (uIL-18), serum monocyte chemoattractant protein-1 (sMCP-1) and tumor necrosis factor-alpha (sTNF-alpha), and incidence of AKI were determined. SUA were divided into tertiles and their association with AKI investigated.

Results: A total of 100 cardiac surgery patients were included for analyses. The 1st, 2nd, and 3rd SUA tertiles were associated with 15.1%, 11.7%, and 54.5% incidence of AKI, respectively. The 3rd SUA tertile, compared to the referent 1st tertile, was associated with an eightfold (OR 8.38, CI95% 2.13-33.05, p=0.002) increased risk for AKI. Patients with AKI on post-operative day 1 (n=11) were then excluded for the purpose of determining the predictive value of SUA to diagnose AKI on postoperative day 2 and during hospital stay. In comparison to the referent 1st tertile, the 3rd tertile SUA was associated with an eightfold increased risk for AKI on post-operative day 2 (adjusted OR 7.94, CI95% 1.50-42.08, P=.015) and a five-fold increased risk for AKI during hospital stay (OR 4.83, CI95% 1.21-19.20, P=.025), respectively. SUA (Area Under Curve, AUC 0.77 (CI95% 0.66-0.88, P<.001), serum creatinine (0.73, CI95% 0.62-0.84, P<.001) and sTNF-alpha (0.76, CI95% 0.65-0.87, P<.001) had the best diagnostic performance measured by the Receiver Operating Characteristics curves.

Conclusions: We conclude that post-operative SUA is associated with an increased risk for AKI and compares well to conventional markers of AKI.

Trial registration: ClinicalTrials.gov NCT01168583.

MeSH terms

  • Acute Kidney Injury / blood*
  • Acute Kidney Injury / epidemiology
  • Acute Kidney Injury / urine
  • Acute-Phase Proteins / urine
  • Biomarkers / blood
  • Biomarkers / urine
  • Cardiac Surgical Procedures / adverse effects*
  • Chemokine CCL2 / blood
  • Chi-Square Distribution
  • Female
  • Florida / epidemiology
  • Humans
  • Incidence
  • Interleukin-18 / urine
  • Length of Stay
  • Lipocalin-2
  • Lipocalins / urine
  • Male
  • Middle Aged
  • Odds Ratio
  • Prospective Studies
  • Proto-Oncogene Proteins / urine
  • ROC Curve
  • Risk Assessment
  • Risk Factors
  • Time Factors
  • Tumor Necrosis Factor-alpha / blood
  • Uric Acid / blood*

Substances

  • Acute-Phase Proteins
  • Biomarkers
  • CCL2 protein, human
  • Chemokine CCL2
  • Interleukin-18
  • LCN2 protein, human
  • Lipocalin-2
  • Lipocalins
  • Proto-Oncogene Proteins
  • Tumor Necrosis Factor-alpha
  • Uric Acid

Associated data

  • ClinicalTrials.gov/NCT01168583