The Effect Of NGAL, L-FABP And KIM-1 In Prognosing And Early Diagnosing AKI Induced By Protobothrops Mucrosquamatus And Trimeresurus Stejnegeri Bites

Objective This study investigated the effect of neutrophil gelatinase-associated lipocalin(NGAL), liver fatty acid binding protein(L-FABP) and kidney injury molecule 1(KIM-1) in prognosing and early diagnosing acute kidney injury(AKI) induced by the snakes which affect blood circulation manily. We hope it could make contribution to the work on prevention and treatment of snakebites. It might also be helpful to the study of AKI early diagnosing.Methods We recruited patients from our emergency department and department of snakebite who conformed to the inclusion and exclusion criteria during 2015.24 hours,48 hours,72 hours,7 days and 10 days after snakebites, the serum creatinine(sCr), blood urea nitrogen(BUN) and uric acid(UA) were measured through automatic biochemical analyzer. The snakebite patients were divided into AKI group and non-AKI group according to RIFLE level diagnostic criteria published by Acute Dialysis Quality Initiative(ADQI) workgroup in 2004. The levels of NGAL, L-FABP and KIM-1 were measured by enzyme linked immunosorbent assay(ELISA) and their differences among groups were compared. The capability of three biomarks on diagnosing AKI induced by snakebites were analyzed by ROC curve and their influence to the mortality was evaluated by Logistic regression.Results We observed 49 patients.23 of them were Protobothrops mucrosquamatus bites and 26 of them were Trimeresurus stejnegeri bites. The change of sCr among AKI group conformed to RIFLE level diagnostic criteria published by ADQI workgroup in 2004. They matched the level of Risk or Injury mostly. Some cases even reached the level of Failure. The numbers of cases in AKI and non-AKI group were 24 and 25 respectively. There was some difference on BUN and UA among two groups, but they all varied in the normal range.2 patients were critical among 24 snakebite victims with AKI. They died within 72 hours although they were send to intensive care unit and received renal replace therapy and other treatments. There was no death in the non-AKI group. The mortalities of two groups were the same(P>0.05). The level of urinary NGAL(uNGAL), urinary L-FABP(uL-FABP) and urinary KIM-1(uKIM-1) in the AKI group were higher than the non-AKI group(P<0.01). But there were no differences in the former biomarks among patients bited by various snakes with AKI(P>0.05). After the analysis of of ROC curve, we found the area under the ROC curve(AUC-ROC) of uNGAL、uKIM-1 and uL-FABP all exceeded 0.7. uL-FABP had the largest AUC-ROC(0.952) and its cut-off was 27.5 ng/ml. Its specificity, sensibility, positive predictive value, negative predictive value, positive likelihood ratio and negative likelihood ratio were secondary among three biomarks. The result of Logistic regression analysis showed that the value of Omnibus test was statistically significant(P<0.05) whereas the tests of regression coefficients were not statistically significant(P>0.05).Conclusions The content of NGAL、L-FABP and KIM-1 in urine could be regarded as early diagnosing biomarks for AKI induced by Protobothrops mucrosquamatus or Trimeresurus stejnegeri bites and L-FABP might be the most excellent. But their effects on the prognosis need further study.