Plasma and urine neutrophil gelatinase-associated lipocalin in septic versus non-septic acute kidney injury in critical illness

Division of Critical Care Medicine, University of Alberta Hospital, University of Alberta, 3C1.16 Walter C Mackenzie Centre, 8440-122 Street, Edmonton, AB T6G2B7, Canada.
European Journal of Intensive Care Medicine (Impact Factor: 5.54). 12/2009; 36(3):452-61. DOI: 10.1007/s00134-009-1724-9
Source: PubMed

ABSTRACT Sepsis is the most common trigger for acute kidney injury (AKI) in critically ill patients. We sought to determine whether there are unique patterns to plasma and urine neutrophil gelatinase-associated lipocalin (NGAL) in septic compared with non-septic AKI.
Prospective observational study.
Two adult ICUs in Melbourne, Australia.
Critically ill patients with septic and non-septic AKI.
Blood and urine specimens collected at enrollment, 12, 24 and 48 h to measure plasma and urine NGAL. Eighty-three patients were enrolled (septic n = 43). Septic AKI patients had more co-morbid disease (p = 0.005), emergency surgical admissions (p < 0.001), higher illness severity (p = 0.008), more organ dysfunction (p = 0.008) and higher white blood cell counts (p = 0.01). There were no differences at enrollment between groups in AKI severity. Septic AKI was associated with significantly higher plasma (293 vs. 166 ng/ml) and urine (204 vs. 39 ng/mg creatinine) NGAL at enrollment compared with non-septic AKI (p < 0.001). Urine NGAL remained higher in septic compared with non-septic AKI at 12 h (p < 0.001) and 24 h (p < 0.001). Plasma NGAL showed fair discrimination for AKI progression (area under receiver-operator characteristic curve 0.71) and renal replacement therapy (AuROC 0.78). Although urine NGAL performed less well (AuROC 0.70, 0.70), peak urine NGAL predicted AKI progression better in non-septic AKI (AuROC 0.82).
Septic AKI patients have higher detectable plasma and urine NGAL compared with non-septic AKI patients. These differences in NGAL values in septic AKI may have diagnostic and clinical relevance as well as pathogenetic implications.

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    ABSTRACT: The RIFLE (Risk, Injury, Failure, Loss, and End-stage kidney disease) criteria were introduced in 2004, defining the clinical stage of acute kidney injury (AKI) and outcome measures based on serum creatinine, glomerular filtration rate, and urine output. However, a growing body of evidence suggests that these markers are insufficient in drawing an accurate illustration of kidney injury. Indeed, mortality and morbidity remain high in AKI, suggesting that accuracy and speed of patient evaluation are lacking. A great deal of evidence indicates that neutrophil gelatinase-associated lipocalin (NGAL) is a sensitive and specific early marker of various etiological classes of AKI and would be highly valuable in conjunction with existing markers of AKI for better classifying renal injury as well as dysfunction (kidney attack). Improvements in diagnosis, risk identification, stratification, prognosis, and therapeutic monitoring will benefit clinical decision-making in the individualized bundling of therapies and ongoing patient management. In particular, kidney protection and AKI prevention may become feasible if an earlier and more accurate diagnosis is made for AKI. Here, we discuss the opportunity to consider whether NGAL is ready for routine clinical use in a number of etiologies of AKI.
    Critical Care 12/2014; 18(6). DOI:10.1186/s13054-014-0680-0 · 5.04 Impact Factor
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    Critical care (London, England) 12/2014; 18(6):716. DOI:10.1186/s13054-014-0716-5
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