Neutrophil-to-lymphocyte Ratio as a Risk Factor for Severe Acute Kidney Injury / 대한신장학회지

ABSTRACT

PURPOSE: To evaluate whether neutrophil-to-lymphocyte ratio (NLR) as a marker of inflammation correlates with the severity of ischemic acute kidney injury (AKI). METHODS: Between January 2003 and December 2008, 84 patients were diagnosed with ischemic AKI. Patients were divided into two groups (prerenal azotemia and acute tubular necrosis; ATN) and analyzed. RESULTS: Of 84 ischemic AKI patients studied, 49 (58%) presented with ATN. NLR on admission was significantly greater in patients with ATN than that in those with prerenal azotemia (7.8+/-7.7 vs. 5.1+/- 3.7; p=0.034). There was a significant and positive correlation between NLR and age (r=0.283; p= 0.009), log C-reactive protein (r=0.409; p=0.001), and log initial and peak serum creatinine (SCr) (r= 0.242; p=0.026 and r=0.294; p=0.007, respectively). Body mass index, hemoglobin and serum albumin concentration were negatively correlated with NLR (r=-0.291; p=0.031, r=-0.254; p=0.020, and r= -0.236; p=0.032, respectively). Thirty-four (41%) patients had severe AKI (RIFLE-F, defined as an absolute increase in SCr of either > or = 0.5 mg/dL or a threefold increase from baseline, or a SCr of more than 4 mg/dL) during hospitalization. A high NLR (>7.5) was associated with the development of severe AKI in multivariate logistic regression analysis. CONCLUSION: High levels of inflammation, as demonstrated by a high NLR, are associated with the severity of ischemic AKI.