Urinary L-FABP and anaemia: distinct roles of urinary markers in type 2 diabetes

Eur J Clin Invest. 2010 Feb;40(2):95-102. doi: 10.1111/j.1365-2362.2009.02220.x. Epub 2009 Nov 11.

Abstract

Background: Urinary liver-type fatty acid binding protein (L-FABP) and kidney injury molecule (KIM)-1, novel urinary biomarkers of renal tubulointerstitial function, have previously been associated with acute ischaemic kidney injury. We studied the clinical significance of urinary L-FABP, KIM-1 and N-acetyl-beta-glucosaminidase (NAG) as potential markers of renal function and chronic ischaemic injury in patients with diabetic nephropathy.

Material and methods: A total of 130 type 2 diabetes patients with early diabetic nephropathy and 40 healthy controls were studied. Urinary L-FABP, KIM-1, NAG, albumin excretion rate (AER) and creatinine clearance were obtained from 24-h urine samples, and correlated with measures of red blood cell count, renal function and metabolic control.

Results: Urinary L-FABP was significantly increased in diabetes patients compared with healthy controls [8.1 (interquartile 0.6-11.6) vs. 2.4 (0.5-3.6) microg/g creatinine, P < 0.001] and correlated with AER (r = 0.276, P = 0.002), creatinine clearance (r = -0.189, P = 0.033) and haemoglobin levels (r = -0.190, P = 0.030). In multivariable linear regression analysis, haemoglobin (beta = -0.247, P = 0.015) and AER (beta = 0.198, P = 0.046) were significant predictors of urinary L-FABP. Prevalent anaemia was independently associated with a 6-fold risk for increased tubulointerstitial kidney damage (upper vs. lower two L-FABP tertiles: OR, 6.06; 95% CI: 1.65-22.23; P = 0.007). Urinary KIM-1 was not significantly associated with kidney function, AER, or measures of red blood cell count while urinary NAG was associated with parameters of glucose control and renal function.

Conclusions: Different urinary biomarkers may reflect distinct pathophysiological mechanisms of tubulointerstitial damage in early diabetic nephropathy: Urinary L-FABP could be a novel biomarker for chronic intrarenal ischaemia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Albumins / analysis
  • Anemia / diagnosis
  • Anemia / epidemiology
  • Anemia / urine*
  • Biomarkers / urine
  • Creatinine / urine
  • Diabetes Mellitus, Type 2 / complications
  • Diabetes Mellitus, Type 2 / urine*
  • Diabetic Nephropathies / urine*
  • Erythrocyte Count
  • Fatty Acid-Binding Proteins / urine*
  • Female
  • Glucose / metabolism
  • Hemoglobins / analysis
  • Hepatitis A Virus Cellular Receptor 1
  • Humans
  • Kidney Failure, Chronic / epidemiology
  • Kidney Failure, Chronic / urine*
  • Kidney Function Tests
  • Male
  • Membrane Glycoproteins / urine*
  • Middle Aged
  • Multivariate Analysis
  • Neoplasm Proteins / urine
  • Receptors, Virus

Substances

  • Albumins
  • Biomarkers
  • Fatty Acid-Binding Proteins
  • HAVCR1 protein, human
  • Hemoglobins
  • Hepatitis A Virus Cellular Receptor 1
  • Membrane Glycoproteins
  • NBAS protein, human
  • Neoplasm Proteins
  • Receptors, Virus
  • Creatinine
  • Glucose