The diagnostic accuracy of plasma neutrophil gelatinase-associated lipocalin in the prediction of acute kidney injury in emergency department patients with suspected sepsis.
OBJECTIVE
We assess the diagnostic accuracy of plasma neutrophil gelatinase-associated lipocalin (NGAL) to predict acute kidney injury in emergency department (ED) patients with suspected sepsis.


METHODS
We conducted a secondary analysis of a prospective observational study of a convenience sample of patients from 10 academic medical center EDs. Inclusion criteria were adult patients aged 18 years or older, with suspected infection or a serum lactate level greater than 2.5 mmol/L; 2 or more systemic inflammatory response syndrome criteria; and a subsequent serum creatinine level obtained within 12 to 72 hours of enrollment. Exclusion criteria were pregnancy, do-not-resuscitate status, cardiac arrest, or dialysis dependency. NGAL was measured in plasma collected at ED presentation. Acute kidney injury was defined as an increase in serum creatinine measurement of greater than 0.5 mg/dL during 72 hours.


RESULTS
There were 661 patient enrolled, with 24 cases (3.6%) of acute kidney injury that developed within 72 hours after ED presentation. Median plasma NGAL levels were 134 ng/mL (interquartile range 57 to 277 ng/mL) in patients without acute kidney injury and 456 ng/mL (interquartile range 296 to 727 ng/mL) in patients with acute kidney injury. Plasma NGAL concentrations of greater than 150 ng/mL were 96% sensitive (95% confidence interval [CI] 79% to 100%) and 51% (95% CI 47% to 55%) specific for acute kidney injury. In comparison, to achieve equivalent sensitivity with initial serum creatinine level at ED presentation required a cutoff of 0.7 mg/dL and resulted in specificity of 17% (95% CI 14% to 20%).


CONCLUSIONS
In this preliminary investigation, increased plasma NGAL concentrations measured on presentation to the ED in patients with suspected sepsis were associated with the development of acute kidney injury. Our findings support NGAL as a promising new biomarker for acute kidney injury; however, further research is warranted.
Shapiro
Nathan I
NI
Beth Israel Deaconess Medical Center, Boston, MA 02116, USA. Nshapiro@bidmc.harvard.edu
Trzeciak
Stephen
S
Hollander
Judd E
JE
Birkhahn
Robert
R
Otero
Ronny
R
Osborn
Tiffany M
TM
Moretti
Eugene
E
Nguyen
H Bryant
HB
Gunnerson
Kyle
K
Milzman
David
D
Gaieski
David F
DF
Goyal
Munish
M
Cairns
Charles B
CB
Kupfer
Kenneth
K
Lee
Seok-Won
SW
Rivers
Emanuel P
EP
D058186:Acute Kidney Injury / Q000097:blood / Q000175:diagnosis* / Q000209:etiology / Q000401:mortality; D000209:Acute-Phase Proteins; D015415:Biomarkers / Q000097:blood; D016001:Confidence Intervals; D003404:Creatinine / Q000097:blood; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D000071068:Lipocalin-2; D054834:Lipocalins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011518:Proto-Oncogene Proteins / Q000097:blood*; D012680:Sensitivity and Specificity; D018805:Sepsis / Q000097:blood / Q000150:complications / Q000175:diagnosis*; D013997:Time Factors
D000209:Acute-Phase Proteins; D015415:Biomarkers; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D011518:Proto-Oncogene Proteins; D003404:Creatinine