Predicting acute kidney injury using urinary liver-type fatty-acid binding protein and serum N-terminal pro-B-type natriuretic peptide levels in patients treated at medical cardiac intensive care units

Crit Care. 2018 Aug 18;22(1):197. doi: 10.1186/s13054-018-2120-z.


Background: The early prediction of acute kidney injury (AKI) can facilitate timely intervention and prevent complications. We aimed to understand the predictive value of urinary liver-type fatty-acid binding protein (L-FABP) levels on admission to medical (non-surgical) cardiac intensive care units (CICUs) for AKI, both independently and in combination with serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels.

Methods: We prospectively investigated the predictive value of L-FABP and NT-proBNP for AKI in a large, heterogeneous cohort of patients treated in medical CICUs. Baseline urinary L-FABP and serum NT-proBNP were measured on admission. AKI was diagnosed according to the Kidney Disease: Improving Global Outcomes criteria. We studied 1273 patients (mean age, 68 years), among whom 46% had acute coronary syndromes, 38% had acute decompensated heart failure, 5% had arrhythmia, 3% had pulmonary hypertension, 2% had acute aortic syndrome, 2% had infective endocarditis, and 1% had Takotsubo cardiomyopathy.

Results: Urinary L-FABP levels correlated with serum NT-proBNP levels (r = 0.17, p < 0.0001). AKI occurred in 224 patients (17.6%), including 48 patients with stage 2 or 3 disease. Patients who developed AKI had higher one-week and 6-month mortality than those who did not develop AKI (p = 0.0002 and p = 0.003, respectively). In the multivariate logistic analysis, both L-FABP (p < 0.0001) and NT-proBNP (p = 0.006) were independently associated with the development of AKI. Adding L-FABP and NT-proBNP to a baseline model that included established risk factors further improved reclassification (p < 0.001) and discrimination (p < 0.01) beyond that of the baseline model or any single biomarker individually.

Conclusions: Urinary L-FABP and serum NT-proBNP levels on admission are independent predictors of AKI, and when used in combination, improve early prediction of AKI in patients hospitalized at medical CICUs.

Keywords: Acute kidney injury; Liver-type fatty-acid binding protein; Medical cardiac intensive care units; N-terminal pro-B-type natriuretic peptide.

MeSH terms

  • Acute Kidney Injury / classification
  • Acute Kidney Injury / diagnosis*
  • Adult
  • Aged
  • Aged, 80 and over
  • Biomarkers / analysis
  • Biomarkers / blood
  • Biomarkers / urine
  • Cohort Studies
  • Fatty Acid-Binding Proteins / analysis*
  • Fatty Acid-Binding Proteins / urine
  • Female
  • Humans
  • Intensive Care Units / organization & administration
  • Male
  • Middle Aged
  • Natriuretic Peptide, Brain / analysis*
  • Natriuretic Peptide, Brain / blood
  • Peptide Fragments / analysis*
  • Peptide Fragments / blood
  • Predictive Value of Tests
  • Prospective Studies


  • Biomarkers
  • FABP1 protein, human
  • Fatty Acid-Binding Proteins
  • Peptide Fragments
  • pro-brain natriuretic peptide (1-76)
  • Natriuretic Peptide, Brain