title: The diagnostic accuracy of plasma neutrophil gelatinase-associated lipocalin in the prediction of acute kidney injury in emergency department patients with suspected sepsis.
abstract: 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.
authors.affiliation: Beth Israel Deaconess Medical Center, Boston, MA 02116, USA. Nshapiro@bidmc.harvard.edu
authors.forename: Nathan I
authors.initials: NI
authors.lastname: Shapiro
authors.forename: Stephen
authors.initials: S
authors.lastname: Trzeciak
authors.forename: Judd E
authors.initials: JE
authors.lastname: Hollander
authors.forename: Robert
authors.initials: R
authors.lastname: Birkhahn
authors.forename: Ronny
authors.initials: R
authors.lastname: Otero
authors.forename: Tiffany M
authors.initials: TM
authors.lastname: Osborn
authors.forename: Eugene
authors.initials: E
authors.lastname: Moretti
authors.forename: H Bryant
authors.initials: HB
authors.lastname: Nguyen
authors.forename: Kyle
authors.initials: K
authors.lastname: Gunnerson
authors.forename: David
authors.initials: D
authors.lastname: Milzman
authors.forename: David F
authors.initials: DF
authors.lastname: Gaieski
authors.forename: Munish
authors.initials: M
authors.lastname: Goyal
authors.forename: Charles B
authors.initials: CB
authors.lastname: Cairns
authors.forename: Kenneth
authors.initials: K
authors.lastname: Kupfer
authors.forename: Seok-Won
authors.initials: SW
authors.lastname: Lee
authors.forename: Emanuel P
authors.initials: EP
authors.lastname: Rivers
mesh_terms: 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
chemical_list: D000209:Acute-Phase Proteins; D015415:Biomarkers; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D011518:Proto-Oncogene Proteins; D003404:Creatinine