title: Innate immune function and mortality in critically ill children with influenza: a multicenter study.
abstract: OBJECTIVE
  To prospectively evaluate relationships among serum cytokine levels, innate immune responsiveness, and mortality in a multicenter cohort of critically ill children with influenza infection.
  
  
  METHODS
  Prospective, multicenter, observational study.
  
  
  METHODS
  Fifteen pediatric ICUs among members of the Pediatric Acute Lung Injury and Sepsis Investigators network.
  
  
  METHODS
  Patients ≤18 yrs old admitted to a PICU with community-acquired influenza infection. A control group of outpatient children was also evaluated.
  
  
  METHODS
  ICU patients underwent sampling within 72 hrs of ICU admission for measurement of a panel of 31 serum cytokine levels and quantification of whole blood ex vivo lipopolysaccharide-stimulated tumor necrosis factor-α production capacity using a standardized stimulation protocol. Outpatient control subjects also underwent measurement of tumor necrosis factor-α production capacity.
  
  
  RESULTS
  Fifty-two patients (44 survivors, eight deaths) were sampled. High levels of serum cytokines (granulocyte macrophage colony-stimulating factor, interleukin-6, interleukin-8, interferon-inducible protein-10, monocyte chemotactic protein-1, and macrophage inflammatory protein-1α) were associated with mortality (p < 0.0016 for each comparison) as was the presence of secondary infection with Staphylococcus aureus (p = 0.007), particularly methicillin-resistant S. aureus (p < 0.0001). Nonsurvivors were immunosuppressed with leukopenia and markedly reduced tumor necrosis factor-α production capacity compared with outpatient control subjects (n = 21, p < 0.0001) and to ICU survivors (p < 0.0001). This association remained after controlling for multiple covariables. A tumor necrosis factor-α response <250 pg/mL was highly predictive of death and longer duration of ICU stay (p < 0.0001). Patients with S. aureus coinfection demonstrated the greatest degree of immunosuppression (p < 0.0001).
  
  
  CONCLUSIONS
  High serum levels of cytokines can coexist with marked innate immune suppression in children with critical influenza. Severe, early innate immune suppression is highly associated with both S. aureus coinfection and mortality in this population. Multicenter innate immune function testing is feasible and can identify these high-risk children.
authors.affiliation: Department of Pediatrics, Critical Care Medicine, Nationwide Children's Hospital, The Ohio State University College of Medicine, Columbus, OH, USA. Mark.Hall@NationwideChildrens.org
authors.forename: Mark W
authors.initials: MW
authors.lastname: Hall
authors.forename: Susan M
authors.initials: SM
authors.lastname: Geyer
authors.forename: Chao-Yu
authors.initials: CY
authors.lastname: Guo
authors.forename: Angela
authors.initials: A
authors.lastname: Panoskaltsis-Mortari
authors.forename: Philippe
authors.initials: P
authors.lastname: Jouvet
authors.forename: Jill
authors.initials: J
authors.lastname: Ferdinands
authors.forename: David K
authors.initials: DK
authors.lastname: Shay
authors.forename: Jyotsna
authors.initials: J
authors.lastname: Nateri
authors.forename: Kristin
authors.initials: K
authors.lastname: Greathouse
authors.forename: Ryan
authors.initials: R
authors.lastname: Sullivan
authors.forename: Tram
authors.initials: T
authors.lastname: Tran
authors.forename: Shannon
authors.initials: S
authors.lastname: Keisling
authors.forename: Adrienne G
authors.initials: AG
authors.lastname: Randolph
mesh_terms: D000293:Adolescent; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D018925:Chemokines / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D016207:Cytokines / Q000097:blood*; D005260:Female; D006801:Humans; D007113:Immunity, Innate; D007223:Infant; D007231:Infant, Newborn; D007251:Influenza, Human / Q000276:immunology* / Q000401:mortality*; D015278:Intensive Care Units, Pediatric; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D011446:Prospective Studies; D018570:Risk Assessment; D014481:United States / Q000453:epidemiology
chemical_list: D015415:Biomarkers; D018925:Chemokines; D016207:Cytokines