title: Neutrophil Gelatinase-Associated Lipocalin, but Not Kidney Injury Marker 1, Correlates with Duration of Delayed Graft Function.
abstract: BACKGROUND
  No specific early biomarker is available to measure kidney injury after kidney transplantation (KT). Both neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury marker 1 (KIM-1) increase after oxidative injury. Their potential as early biomarkers was evaluated in this one-arm pilot study.
  
  
  METHODS
  Twenty consecutive KT patients receiving a kidney from a donation after circulatory death donor were included. Graft perfusate was collected, as well as serum samples before transplantation, at the end of surgery, and 1, 4, and 7 days after transplantation. NGAL and KIM-1 were measured using ELISA. Kidney function and delayed graft function (DGF) were monitored.
  
  
  RESULTS
  In this cohort, 85% of the KT patients developed DGF. Perfusate NGAL correlated with donor age (r2 = 0.094, p = 0.01) and serum creatinine (r2 = 0.243, p = 0.05). A cardiac cause of death was associated with higher NGAL in the perfusate (p = 0.03). Serum NGAL at day 1 was significantly higher in patients with DGF (730 ng/ml, range 490-1,655, vs. 417 ng/ml, range 232-481; p = 0.01). Serum NGAL levels at day 1, 4, and 7 correlated with the duration of DGF. KIM-1 was not detectable in the perfusate or in the serum until postoperative day 4 in 80% of patients.
  
  
  CONCLUSIONS
  NGAL in the perfusate correlates with known donor risk factors for DGF. For the first time, we describe that serum NGAL at day 1 can discriminate between DGF and immediate graft function. Also, serum NGAL levels at day 1, 4, and 7 correlate with the duration of DGF. No association with KIM-1 was found. These data suggest that NGAL may be used as an early biomarker to detect DGF and warrants further study.
authors.affiliation: Division of HPB and Transplant Surgery, Department of Surgery, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
authors.forename: Eline Kristina
authors.initials: EK
authors.lastname: van den Akker
authors.forename: Dennis Alexander
authors.initials: DA
authors.lastname: Hesselink
authors.forename: Olivier Christiaan
authors.initials: OC
authors.lastname: Manintveld
authors.forename: Jan Nicolaas Maria
authors.initials: JN
authors.lastname: IJzermans
authors.forename: Ronald Wilhelm Frederik
authors.initials: RW
authors.lastname: de Bruijn
authors.forename: Frank Johan Marinus Frederik
authors.initials: FJ
authors.lastname: Dor