title: Tubular urinary biomarkers do not identify aetiology of acute kidney injury in kidney transplant recipients.
abstract: OBJECTIVE
  To evaluate the performance of urinary neutrophil gelatinase-associated lipocalin (uNGAL), kidney injury molecule, interleukin-18 and heat shock protein 72 for differential diagnosis between causes of acute kidney injury in kidney transplant recipients, especially immunological rejection.
  
  
  METHODS
  We measured these biomarkers in 67 kidney transplant recipients with acute kidney injury according to the RIFLE criteria.
  
  
  RESULTS
  There were no statistical differences in biomarkers between kidney transplant recipients with immunological rejection (n = 20), pre-renal causes (n = 20) and other AKI causes (n = 27). Only the uNGAL level relative to urinary creatinine (uNGAL/uCr) for immunological rejection was different in comparison with others (P < 0.001); a cut-off of 59 μg/g of uNGAL/uCr had a sensitivity and specificity of 60% and 58% respectively (area under the curve in receiver-operating characteristic curve, 0.65). The other biomarkers were not useful in differentiating the causes of acute kidney injury.
  
  
  CONCLUSIONS
  The biomarkers tested are not useful in identifying immunological rejection as cause of acute kidney injury in kidney transplant recipients.
authors.affiliation: Department of Nephrology and Mineral Metabolism, National Institute of Medical Sciences and Nutrition Salvador Zubirán, Mexico City, DF, Mexico.
authors.forename: Juan C
authors.initials: JC
authors.lastname: Ramirez-Sandoval
authors.forename: Jonatan
authors.initials: J
authors.lastname: Barrera-Chimal
authors.forename: Perla E
authors.initials: PE
authors.lastname: Simancas
authors.forename: Ricardo
authors.initials: R
authors.lastname: Correa-Rotter
authors.forename: Norma A
authors.initials: NA
authors.lastname: Bobadilla
authors.forename: Luis E
authors.initials: LE
authors.lastname: Morales-Buenrostro
mesh_terms: D058186:Acute Kidney Injury / Q000175:diagnosis / Q000209:etiology / Q000652:urine; D000209:Acute-Phase Proteins / Q000652:urine; D000328:Adult; D015415:Biomarkers / Q000652:urine; D003937:Diagnosis, Differential; D005260:Female; D006084:Graft Rejection / Q000175:diagnosis / Q000209:etiology / Q000652:urine; D050884:HSP72 Heat-Shock Proteins / Q000652:urine; D000072596:Hepatitis A Virus Cellular Receptor 1; D006801:Humans; D020382:Interleukin-18 / Q000652:urine; D016030:Kidney Transplantation / Q000009:adverse effects*; D007684:Kidney Tubules / Q000378:metabolism*; D000071068:Lipocalin-2; D054834:Lipocalins / Q000652:urine; D008297:Male; D008562:Membrane Glycoproteins / Q000652:urine; D008875:Middle Aged; D011518:Proto-Oncogene Proteins / Q000652:urine; D012372:ROC Curve; D011991:Receptors, Virus; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D000209:Acute-Phase Proteins; D015415:Biomarkers; C491143:HAVCR1 protein, human; D050884:HSP72 Heat-Shock Proteins; D000072596:Hepatitis A Virus Cellular Receptor 1; D020382:Interleukin-18; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D008562:Membrane Glycoproteins; D011518:Proto-Oncogene Proteins; D011991:Receptors, Virus
keywords: AKI; biomarker; kidney transplantation; sensitivity; specificity