Evaluation of new acute kidney injury biomarkers in a mixed intensive care unit.

Abstract

OBJECTIVE:

Biomarkers for detection of acute kidney injury and prediction of mortality will be useful to improve the outcomes of critically ill patients. Although several promising acute kidney injury biomarkers have been reported, evaluation in heterogeneous disease-oriented populations is necessary to confirm their reliability before their translation to clinical use. This study was undertaken to evaluate the reliability of new acute kidney injury biomarkers including urinary L-type fatty acid-binding protein with heterogeneous intensive care unit populations.

DESIGN:

Prospective observational cohort study.

SETTING:

Single-center study, 15-bed medical-surgical mixed intensive care unit at a university hospital.

PATIENTS:

Three hundred thirty-nine adult critically ill patients who had been admitted to the intensive care unit were studied prospectively.

INTERVENTIONS:

None.

MEASUREMENTS AND MAIN RESULTS:

Five urinary biomarkers (L-type fatty acid-binding protein, neutrophil gelatinase-associated lipocalin, interleukin-18, N-acetyl-β-D-glucosaminidase, and albumin) were measured at intensive care unit admission. By the RIFLE (Risk, Injury, Failure, Loss, End-stage kidney disease) criteria, 131 patients (39%) were diagnosed as acute kidney injury. Urinary L-type fatty acid-binding protein detected acute kidney injury better than the other biomarkers did (the area under the receiver operating characteristic curves for L-type fatty acid-binding protein 0.75, neutrophil gelatinase-associated lipocalin 0.70, interleukin-18 0.69, N-acetyl-β-D-glucosaminidase 0.62, albumin 0.69). Urinary L-type fatty acid-binding protein predicted later-onset acute kidney injury after intensive care unit admission with the highest area under the receiver operating characteristic curve value of 0.70. Furthermore, L-type fatty acid-binding protein, neutrophil gelatinase-associated lipocalin, and interleukin-18 were able to predict 14-day mortality with higher area under the receiver operating characteristic curves than acute kidney injury detection (area under the receiver operating characteristic curve for L-type fatty acid-binding protein 0.90, neutrophil gelatinase-associated lipocalin 0.83, interleukin-18 0.83). The combination of L-type fatty acid-binding protein and neutrophil gelatinase-associated lipocalin improved mortality prediction (area under the receiver operating characteristic curve 0.93).

CONCLUSION:

This prospective observational study with a cohort of heterogeneous patients treated in a mixed intensive care unit revealed that new acute kidney injury biomarkers have a significantly and moderately predictive use for acute kidney injury diagnosis and that urinary L-type fatty acid-binding protein and neutrophil gelatinase-associated lipocalin can serve as new biomarkers of mortality prediction in critical care.

• Authors: Kent Doi, Kousuke Negishi, Tomoko Ishizu, Daisuke Katagiri, Toshiro Fujita, Takehiro Matsubara, Naoki Yahagi, Takeshi Sugaya, Eisei Noiri
• Journal: Critical care medicine (Crit Care Med) Vol. 39 Issue 11 Pg. 2464-9 (Nov 2011) ISSN: 1530-0293 [Electronic] United States
• PMID: 21705884 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Biomarkers
• Fatty Acid-Binding Proteins
• Interleukin-18
• Lipocalins
• Acetylglucosaminidase

Topics

• Acetylglucosaminidase (urine)
• Acute Kidney Injury (urine)
• Aged
• Albuminuria
• Biomarkers
• Critical Illness
• Fatty Acid-Binding Proteins (urine)
• Female
• Hospitals, University
• Humans
• Intensive Care Units
• Interleukin-18 (urine)
• Lipocalins (urine)
• Male
• Middle Aged
• Prospective Studies
• Sensitivity and Specificity