MO379EVALUATION OF NEUTROPHIL-LYMPHOCYTE RATIO IN PROGNOSIS OF SEVERE ACUTE RENAL INJURY
Authors: Chen Lei , Wei Limin 
Published: May 2021

Abstract

Background and Aims
Recently, more and more attention has been paid to the predictive value of neutrophil to lymphocyte ratio (NLR) in various diseases. As a novel marker for inflammatory response, NLR has been proved to be useful for the diagnosis and prognosis evaluation of inflammatory diseases such as tumor, diabetes, atherosclerosis and other disease. It is well known that inflammatory response plays an important role in the occurrence and development of AKI. Previous studies have shown that NLR has a great value in the diagnosis of AKI, but its value in the prognosis evaluation in AKI patients, especially in critical ill patients with AKI, remains unclear. This study aimed at investigating the predictive value of neutrophil-lymphocyte ratio (NLR) on the risk of 90-day mortality in critically ill patients with acute kidney injury (AKI), so as to provide a simple, feasible, and valuable tool for the prognosis assessment of such patients.

Method
The data of 802 critically ill patients with AKI admitted to the intensive care unit of the First Affiliated Hospital of Xi'an Jiaotong University from January 2015 to December 2019 were retrospectively analyzed. According to the initial NLR level at admission, they were divided into a low NLR group (NLR≤9) and a high NLR group (NLR&gt;9). Differences in comorbidities, the initial Sequential Organ Failure Assessment (SOFA) score, white blood cell (WBC), neutrophil percentage (Neu%), hemoglobin (Hb), platelet (PLT), lactic acid (Lac), pH, blood glucose (Glu), creatine kinase (CK), and all-cause mortality at 90-day were compared between groups. Binary Logistic regression model was used to analyze the risk factors for 90-day mortality in critically ill patients with AKI, and the receiver operating characteristic (ROC) curve was computed to evaluate the predictive value of NLR for the risk of 90-day mortality in such patients.

Results
There were no statistically significant differences in age, sex, and Glu between the two groups. The SOFA score, WBC, Hb, Plt, Lac, CK, SC, BUN and NEU％of patients in the high NLR group were higher than those in the low NLR group, while the BMI and pH value was lower in the high NLR group than that in the low NLR group. The 90-day mortality rate was significantly higher in the high NLR group than that in the low NLR group (36.2% vs 16%, P &lt; 0.001). Binary Logistic regression showed that NLR was an independent risk factor for 90-day mortality in critically ill patients with AKI (OR＝2.402, 95% CI:1.633-3.533,ï¼°＜0.001), even after adjusting for age, gender, BMI, comorbidities, SOFA score, and AKI stages. The area under the ROC curve (AUC) of NLR predicting 90-day mortality was 0.613 with a highest prognostic cut-off point of 8. The sensitivity was 65.77%, and the specificity was 54.78%.

Conclusion
NLR has a predictive value on risk of the 90-day mortality in critically ill patients with AKI. As a simple and easily available clinical indicator, NLR could be applied as a valuable tool in guiding the initial treatment of such patients.