title: Neutrophil CD64 expression as a longitudinal biomarker for severe disease and acute infection in critically ill patients.
abstract: BACKGROUND
  Neutrophilic granulocytes express cluster of differentiation 64 (CD64) antigen upon activation. CD64 can be used as a marker of bacterial infection and sepsis. The goal of this study was to determine whether CD64 is a useful biomarker for critically ill patients and analyze longitudinal measurements with regard to outcome and sepsis severity.
  
  
  METHODS
  In this prospective observational study, CD64 analysis was performed daily until discharge from ICU or death. Demographics, clinical, laboratory data, and outcome defined as 28-day survival were recorded. Patients were included when admitted to the ICU with sepsis, severe sepsis, or septic shock and within 24 h from start of antibiotic treatment.
  
  
  RESULTS
  Hundred and fifty-five consecutive patients were enrolled. At baseline, a difference in CD64 of 2.26 (1.33-4.47) vs. 1.49 (0.89-2.24) (P = 0.004) was seen between patients with a positive culture and negative culture. CD64 at day 1 was higher with patients with septic shock when compared with sepsis (P = 0.012). No difference of CD64 between survivors and nonsurvivors was seen.
  
  
  CONCLUSIONS
  This study demonstrated that CD64 discriminates between critically ill patients with culture positive and negative sepsis and correlates with severity of disease. However, CD64 index is not a good predictor for 28-day mortality in the critically ill patient.
authors: Department of Intensive Care Medicine, VU University Medical Center, Amsterdam, The Netherlands.
authors: E
authors: http://orcid.org/0000-0002-5274-9713
authors: E
authors: de Jong
authors: Department of Intensive Care Medicine, University Medical Center Utrecht, Utrecht, The Netherlands.
authors: D W
authors: DW
authors: de Lange
authors: Department of Intensive Care, VU University Medical Center, Amsterdam, The Netherlands.|Department of Intensive Care, Medisch Spectrum Twente, Enschede, The Netherlands.
authors: A
authors: A
authors: Beishuizen
authors: Department of Epidemiology and Biostatistics, VU University Medical Center, Amsterdam, The Netherlands.
authors: P M
authors: PM
authors: van de Ven
authors: Department of Intensive Care Medicine, VU University Medical Center, Amsterdam, The Netherlands.
authors: A R J
authors: AR
authors: Girbes
authors: Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, Utrecht, The Netherlands. a.huisman@umcutrecht.nl.
authors: A
authors: A
authors: Huisman
mesh_terms: D000208:Acute Disease; D015415:Biomarkers / Q000097:blood; D016638:Critical Illness; D018572:Disease-Free Survival; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D008297:Male; D009504:Neutrophils / Q000378:metabolism*; D011237:Predictive Value of Tests; D017452:Receptors, IgG / Q000096:biosynthesis*; D012720:Severity of Illness Index; D012772:Shock, Septic / Q000097:blood* / Q000401:mortality*; D015996:Survival Rate
chemical_list: D015415:Biomarkers; D017452:Receptors, IgG
keywords: CD64; biomarker; critically ill; infection; sepsis