BACKGROUND: Different molecular forms of urinary neutrophil gelatinase-associated lipocalin (NGAL) have recently been discovered. We aimed to explore the nature, source and discriminatory value of urinary NGAL in intensive care unit (ICU) patients. METHODS: We simultaneously measured plasma NGAL (pNGAL), urinary NGAL (uNGAL), and estimated monomeric and homodimeric uNGAL contribution using Western blotting-validated enzyme-linked immunosorbent assays [uNGAL(E1) and uNGAL(E2)] and their calculated ratio in 102 patients with the systemic inflammatory response syndrome and oliguria, and/or a creatinine rise of >25 μmol/L. MEASUREMENTS AND MAIN RESULTS: Bland-Altman analysis demonstrated that, despite correlating well (r = 0.988), uNGAL and uNGAL(E1) were clinically distinct, lacking both accuracy and precision (bias: 266.23; 95% CI 82.03-450.44 ng/mg creatinine; limits of agreement: -1,573.86 to 2,106.32 ng/mg creatinine). At best, urinary forms of NGAL are fair (area under the receiver operating characteristic [AUROC] ≤0.799) predictors of renal or patient outcome; most perform significantly worse. The 44 patients with a primarily monomeric source of uNGAL had higher pNGAL (118.5 ng/ml vs. 72.5 ng/ml; p < 0.001), remaining significant following Bonferroni correction. CONCLUSIONS: uNGAL is not a useful predictor of outcome in this ICU population. uNGAL patterns may predict distinct clinical phenotypes. The nature and source of uNGAL are complex and challenge the utility of NGAL as a uniform biomarker.
BACKGROUND: Different molecular forms of urinary neutrophil gelatinase-associated lipocalin (NGAL) have recently been discovered. We aimed to explore the nature, source and discriminatory value of urinary NGAL in intensive care unit (ICU) patients. METHODS: We simultaneously measured plasma NGAL (pNGAL), urinary NGAL (uNGAL), and estimated monomeric and homodimeric uNGAL contribution using Western blotting-validated enzyme-linked immunosorbent assays [uNGAL(E1) and uNGAL(E2)] and their calculated ratio in 102 patients with the systemic inflammatory response syndrome and oliguria, and/or a creatinine rise of >25 μmol/L. MEASUREMENTS AND MAIN RESULTS: Bland-Altman analysis demonstrated that, despite correlating well (r = 0.988), uNGAL and uNGAL(E1) were clinically distinct, lacking both accuracy and precision (bias: 266.23; 95% CI 82.03-450.44 ng/mg creatinine; limits of agreement: -1,573.86 to 2,106.32 ng/mg creatinine). At best, urinary forms of NGAL are fair (area under the receiver operating characteristic [AUROC] ≤0.799) predictors of renal or patient outcome; most perform significantly worse. The 44 patients with a primarily monomeric source of uNGAL had higher pNGAL (118.5 ng/ml vs. 72.5 ng/ml; p < 0.001), remaining significant following Bonferroni correction. CONCLUSIONS: uNGAL is not a useful predictor of outcome in this ICU population. uNGAL patterns may predict distinct clinical phenotypes. The nature and source of uNGAL are complex and challenge the utility of NGAL as a uniform biomarker.
Authors: Mitchell M Levy; William L Macias; Jean-Louis Vincent; James A Russell; Eliezer Silva; Benjamin Trzaskoma; Mark D Williams Journal: Crit Care Med Date: 2005-10 Impact factor: 7.598
Authors: Hilde R H de Geus; Jan Bakker; Emmanuel M E H Lesaffre; Jos L M L le Noble Journal: Am J Respir Crit Care Med Date: 2010-10-08 Impact factor: 21.405
Authors: Andrea Lassnigg; Daniel Schmidlin; Mohamed Mouhieddine; Lucas M Bachmann; Wilfred Druml; Peter Bauer; Michael Hiesmayr Journal: J Am Soc Nephrol Date: 2004-06 Impact factor: 10.121
Authors: Kathleen D Liu; Wei Yang; Alan S Go; Amanda H Anderson; Harold I Feldman; Michael J Fischer; Jiang He; Radhakrishna R Kallem; John W Kusek; Stephen R Master; Edgar R Miller; Sylvia E Rosas; Susan Steigerwalt; Kaixiang Tao; Matthew R Weir; Chi-Yuan Hsu Journal: Am J Kidney Dis Date: 2014-10-11 Impact factor: 8.860
Authors: John Richard Prowle; Paolo Calzavacca; Elisa Licari; E Valentina Ligabo; Jorge E Echeverri; Sean M Bagshaw; Anja Haase-Fielitz; Michael Haase; Vaughn Ostland; Eisei Noiri; Mark Westerman; Prasad Devarajan; Rinaldo Bellomo Journal: Ren Fail Date: 2015-01-14 Impact factor: 2.606
Authors: Soman Sen; Zack R Godwin; Tina Palmieri; David Greenhalgh; Amanda N Steele; Nam K Tran Journal: J Surg Res Date: 2015-03-20 Impact factor: 2.192