Evaluation the performance of serum neutrophil gelatinase associated lipocalin as a biomarker of allograft dysfunction in kidney recipients from living donors

Introduction: Serum neutrophil gelatinase-associated lipocalin (sNGAL) has been proposed as an early biomarker for the prediction of delayed graft function (DGF) from cadaveric donors. Objectives: The purposes of this investigation were to explore the time-based trend for sNGAL in kidney recipients from living donors and to evaluate its correlation with graft function recovery during a one-year follow-up. Patients and Methods: Kidney recipients (n=39) were consecutively enrolled. Sample collection was performed before transplantation and at 2, 16, 24, 36, 48 hours after surgery. Kidney recipients were split into immediate graft function (IGF) and DGF based on estimated glomerular filtration rate (eGFR) on day 5 post-surgery. eGFRs >60 mL/min/1.73 m2 on day 5 post-transplantation were considered as IGF. sNGAL was assessed by ELISA. Serum creatinine (sCr) was measured by the Jaffe method. Results: Rates of participants with IGF or DGF were 25 and 14, respectively. Pre-surgery, sNGAL levels in the DGF subset were 21% higher than that of the IGF group. At 2-hours checkpoint, area under curve, sensitivity, specificity and cut-off (ng/mL) for sNGAL were 0.73, 100%, 52% and 151.8. sNGAL levels correlated with allograft function at 6, 9 and 12 months post-transplantation (r=0.66; P=0.007; r=0.836; P=0.031 and r=0.93; P=0.016). Conclusion: We have uncovered that monitoring sNGAL in kidney recipients is a useful biomarker for the evaluation of short- and long postoperative outcome in renal transplant patients from living donors. However, multicenter study with large samples-size is required to ascertain the usefulness of sNGAL as diagnostic tool for the evaluation of allograft dysfunction in renal transplant patients from living donors.