The Value Of SCS Perfusate Biomarkers For Predicting Delayed Graft Function Of DCD Donor Kidneys

Objective: To explore the possibilities of SCS perfusate biomarkers predicting delayed graft function(DGF)in donor of cardiac death(DCD)kidneys.Method: A total of 64 patients who received renal transplantation from DCD donor during Aug.7th 2016 to Dec.13 th 2016,was included in this research.We performed a prospective study and analyzed perfusate samples of SCS stored DCD kidneys for 4 unique biomarkers,which were NGAL?L-FABP?KIM-1 and IL-18.Patients were divided into two groups by whom developed DGF,defined as DGF group and whom did not,defined as immediate graft functioning group(IGF).We compared the concentration differences of the 4 biomarkers between DGF group and IGF group to find out the correlativity of biomarker concentrations and DGF incidence,in order to predict donor kidney functions.And we also drew the receiver operating characteristic curves(ROC curve)to find out the cut-off value to prediagnose DGF in DCD kidney receivers.Results: Among 64 patients,7 patients developed DGF.The incidence of DGF was 10.9%.ALL four biomarkers were detectable in perfusate samples.Even though the detect rate of IL-18 was low about 60.9% when compared with the other 3 markers which were all over 95%.Perfusate NGAL concentration was significantly different between DGF group and IGF group(p = 0.009).Neither L-FABP?KIM-1 nor IL-18 perfusate concentration was found statistically different between DGF group and IGF group.(p=0.834/0.124/0.318,respectively).Higher NGAL concentration in the perfusate was associated with DGF(r = 0.430,p< 0.001),so as to the serum creatinine level at day 1?2?3 and 7(r=0.321,P=0.01;r=0.416,P=0.001;r=0.489,P<0.001;r=0.535,P<0.001,respectively).And the serum creatinine reduction rates of the 2nd and 3rd day were also found associated with DGF(r=-0.373,P=0,002 and r=-0.37,P=0,03).The cut-off value of the NGAL concentration is 204.13ng/ml with AUC=0.879?pre-diagnose sensitivity of 100% and specificity of 71.9%.However,when combined NGAL with KIM-1 concentration,the pre-diagnose value was elevated into sensitivity of 100%?specificity of 75.4% and AUC was 0.932.And the pre-diagnostic value was seen even higher with NGAL?KIM-1 and third day creatinine level after operation combined analysis.The area under ROC curve was 0.975 with 100% in sensibility and 86% in specificity.Conclusions: This is the first time that all these four biomarkers were found detectable in SCS perfusate that was ever reported.We find out that the NGAL in perfusate samples is associated with the incidence of DGF.And some of the biomarkers(NGAL and KIM-1)are truly pre-diagnostic valuable in predicting DGF and even more so when combined with each other or with serum creatinine levels.This data suggests that these biomarkers may be used as an early biomarker to detect DGF and warrants further study.