A combination of SOFA score and biomarkers gives a better prediction of septic AKI and in-hospital mortality in critically ill surgical patients: a pilot study

Abstract

BackgroundSepsis is a syndrome characterized by a constellation of clinical manifestations and a significantly high mortality rate in the surgical intensive care unit (ICU). It is frequently complicated by acute kidney injury (AKI), which, in turn, increases the risk of mortality. Therefore, it is of paramount importance to identify those septic patients at risk for the development of AKI and mortality. The objective of this pilot study was to evaluate several different biomarkers, including NGAL, calprotectin, KIM-1, cystatin C, and GDF-15, along with SOFA scores, in predicting the development of septic AKI and associated in-hospital mortality in critically ill surgical patients.MethodsPatients admitted to the surgical ICU were prospectively enrolled, having given signed informed consent. Their blood and urine samples were obtained and subjected to enzyme-linked immunosorbent assay (ELISA) to determine the levels of various novel biomarkers. The clinical data and survival outcome were recorded and analyzed.ResultsA total of 33 patients were enrolled in the study. Most patients received surgery prior to ICU admission, with abdominal surgery being the most common type of procedure (27 patients (81.8%)). In the study, 22 patients had a diagnosis of sepsis with varying degrees of AKI, while the remaining 11 were free of sepsis. Statistical analysis demonstrated that in patients with septic AKI versus those without, the following were significantly higher: serum NGAL (447.5 ± 35.7 ng/mL vs. 256.5 ± 31.8 ng/mL, P value 0.001), calprotectin (1030.3 ± 298.6 pg/mL vs. 248.1 ± 210.7 pg/mL, P value 0.049), urinary NGAL (434.2 ± 31.5 ng/mL vs. 208.3 ± 39.5 ng/mL, P value < 0.001), and SOFA score (11.5 ± 1.2 vs. 4.4 ± 0.5, P value < 0.001). On the other hand, serum NGAL (428.2 ± 32.3 ng/mL vs. 300.4 ± 44.3 ng/mL, P value 0.029) and urinary NGAL (422.3 ± 33.7 ng/mL vs. 230.8 ± 42.2 ng/mL, P value 0.001), together with SOFA scores (10.6 ± 1.4 vs. 5.6 ± 0.8, P value 0.003), were statistically higher in cases of in-hospital mortality. A combination of serum NGAL, urinary NGAL, and SOFA scores could predict in-hospital mortality with an AUROC of 0.911.ConclusionsThis pilot study demonstrated a promising panel that allows an early diagnosis, high sensitivity, and specificity and a prognostic value for septic AKI and in-hospital mortality in surgical ICU. Further study is warranted to validate our findings.Electronic supplementary materialThe online version of this article (10.1186/s13017-018-0202-5) contains supplementary material, which is available to authorized users.

Potential Prognostic Markers of Acute Kidney Injury in the Early Phase of Acute Pancreatitis

“…Heller et al [91] and Seibert et al [92] reported the usefulness of calprotectin measurements in urine in the detection of AKI. The diagnostic sensitivity and specificity were high (over 90%), although the cut-off values differed between the studies from 219.8 ng/mL [93] to 440 ng/mL [92]. The usefulness of urine calprotectin has also been reported by Chang et al [94], who studied patients admitted to coronary care unit.…”

“…They reported high diagnostic accuracy (area under the ROC curve of 0.946) for the diagnosis of AKI [94]. Gao et al [95] and Lee et al [93] observed higher urine calprotectin in patients with sepsis complicated with AKI (with areas under the ROC curves of 0.901 and 0.889, respectively). Again, there are no studies in AP patients.…”

Prognostic and predictive enrichment in sepsis

“…To date, few successful enrichment strategies have been proposed for the prediction of sepsis-associated AKI. Although the data remain sparse, existing attempts have utilized single biomarkers [85][86][87][88][89][90][91][92] , panels of known biomarkers 93 , microarray for the identification of novel candidate biomarkers 94 and clinical parameters [95][96][97] for AKI prediction and prognostic enrichment.…”

“…In another study, the combination of high central venous pressure and elevated renal resistive indices, as measured by ultrasound in patients with sepsis, was found to be a sensitive, early predictor of sepsis-associated AKI 95 . More recently, a pilot study combining sequential organ failure assessment scores and biomarker measurements (specifically, serum and urine NGAL) demonstrated the ability to predict AKI and mortality with good sensitivity and specificity 96 . However, as discussed in previous sections, although pragmatic approaches such as these are attractive because of their simplicity, they are unlikely to capture the complexity of the ongoing pathophysiology leading to the development of sepsis-associated AKI.…”

Mortality prediction of serum neutrophil gelatinase-associated lipocalin in patients requiring continuous renal replacement therapy

“…Previous studies have shown that NGAL levels can predict overall mortality in patients with critical illness, however, most of those studies were performed in patients with sepsis or in postoperative status [10][11][12][13]. A mortality analysis study focusing on serum NGAL levels in critically ill patients with AKI was a small study, involving only 50 patients [13].…”