Performance of plasma measurement of neutrophil gelatinase-associated lipocalin as a biomarker of bacterial infections in the intensive care unit

J Crit Care. 2019 Oct:53:264-270. doi: 10.1016/j.jcrc.2019.07.001. Epub 2019 Jul 2.

Abstract

Purpose: To assess the value of dimeric neutrophil-gelatinase associated lipocalin (NGAL) as an early marker of bacterial infection and its response to antibiotic therapy in intensive care unit (ICU) patients.

Materials & methods: We measured daily plasma dNGAL in 198 patients admitted to a mixed ICU. Likelihood of infection was determined with International Sepsis Forum criteria. We measured dNGAL in 145 healthy controls to establish normal values.

Results: ICU patients had higher dNGAL than healthy controls. A suspected or confirmed infection was independently associated with 90% (95% CI 15-215%) higher dNGAL than absence of infection. We observed no association between acute kidney injury and dNGAL. Diagnostic accuracy at antibiotic treatment initiation, assessed with area under the receiver-operating characteristics curve (AUC-ROC), for dNGAL was 0.70 (95% CI 0.60-0.79). AUC-ROC for dNGAL 24 h before antibiotic treatment initiation was 0.54 (95% CI 0.41-0.66). The mean (95% CI) change of dNGAL in the first 2 days after appropriate antibiotic therapy initiation was -31 (-49,-13)%.

Conclusions: In our cohort of ICU patients, plasma dNGAL was associated with presence of bacterial infections independent of AKI but it performed poor as a predictor of infections. Following antibiotic therapy, dNGAL markedly decreased-supporting further exploration of dNGAL-guided antibiotic de-escalation.

Publication types

  • Multicenter Study
  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Kidney Injury / blood
  • Adult
  • Aged
  • Area Under Curve
  • Bacterial Infections / diagnosis*
  • Biomarkers / metabolism*
  • British Columbia
  • Critical Care
  • Female
  • Humans
  • Intensive Care Units
  • Lipocalin-2 / metabolism*
  • Male
  • Middle Aged
  • Prospective Studies
  • ROC Curve
  • Sepsis / complications
  • Sepsis / diagnosis

Substances

  • Biomarkers
  • LCN2 protein, human
  • Lipocalin-2