The diagnostic and prognostic values of serum and urinary kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin in sepsis induced acute renal injury patients

OBJECTIVE: The kidney injury molecule-1 (uKIM-1) and neutrophil gelatinase-associated lipocalin (uNGAL, sNGAL) have been demonstrated to be diagnostic biomarkers for acute kidney injury (AKI) in a variety of diseases. However, both of them were not well validated in sepsis patients with acute kidney injury. PATIENTS AND METHODS: This was a prospective and observational study which was performed in the three intensive care units of the Beijing Chao-Yang Hospital. Over a 12-month period, 174 patients ( 70 sepsis patients, 69 sepsis with AKI and 35 controls) were enrolled. Blood and urinary specimens were collected at admission as soon as possible (within 24 hours) and KIM-1 and NGAL levels were tested. RESULTS: Levels of uKIM-1, uNGAL, sNGAL were significantly higher in the sepsis patients who developed AKI compared to those sepsis with no-AKI (0.88 ng/ml (0.37, 2.14) vs. 1.21 ng/ml (0.67, 3.26) p=0.003, 63.54 ng/ml (21.66, 125.45) vs. 249.85 ng/ml (86.60, 585.97) p<0.001, and 108.08 ng/ml (67.74, 212.22) vs. 200.01 ng/ml (102.76, 300.77) p= 0.001, respectively). sKIM-1 also had significant differences between the two groups (83.98 pg/ml (54.00,147.08) vs. 193.41 pg/ml (106.90, 430.60) p< 0.001). The four biomarkers (uKIM-1, sKIM-1, uNGAL, sNGAL) all could be predictive for AKI, and the areas under the receiver operating characteristic curves (AUROC) were 0.607, 0.754, 0.768, 0.658, respectively. The uNGAL was an independent risk factor for septic AKI, and the AUROC was 0.768 (95% CI: 0.689 to 0.835). The uNGAL and sNGAL were related to the prognosis of sepsis. CONCLUSIONS: Our results showed that NGAL was a promising biomarker of septic AKI. Like the uKIM-1, the sKIM-1 could early predict the occurrence of septic AKI too, but both of them did not have the predictive value in judging the severity of AKI and the prognosis of sepsis.