title: Elevated serum interleukin-10 at time of hospital admission is predictive of mortality in patients with Staphylococcus aureus bacteremia.
abstract: BACKGROUND
  Staphylococcus aureus bacteremia (SaB) carries considerable morbidity and mortality. We examined the predictive value of serum concentrations of interleukin (IL)-10, proinflammatory cytokines, and terminal complement on patient survival and SaB duration.
  
  
  METHODS
  Clinical information on consecutive patients with SaB at a tertiary medical center were collected prospectively. Patient serum samples obtained at the day of clinical presentation were assayed for tumor necrosis factor-α, IL-1β, IL-10, and complement membrane attack complex C5b-9 concentrations using enzyme-linked immunoassay. Logistic regression identified predictors of mortality and duration of bacteremia.
  
  
  RESULTS
  In 59 patients with SaB, 14% died and 17% had prolonged bacteremia (>4 days). Elevated IL-10 serum concentrations (>7.8 pg/mL) identified all 8 patients who died, whereas there were no deaths in patients with normal IL-10 (P = .016). The lack of an IL-1β response (≤0.45 pg/mL) defined all patients with SaB >4 days. In multivariate analysis, patient age (odds ratio [OR], 1.16; P = .022), duration of bacteremia (OR, 1.16; P = .031), and serum IL-10 (OR, 1.05; P = .014) were identified as independent predictors of patient mortality.
  
  
  CONCLUSIONS
  SaB mortality was confined strictly to patients with elevated IL-10 concentrations. We recommend that future clinical trials of SaB stratify patients according to IL-10 and IL-1β serum concentrations in order to better evaluate the impact of therapeutic interventions on patient outcome.
authors.affiliation: School of Pharmacy, University of Wisconsin, Madison, WI 53705, USA. werose@pharmacy.wisc.edu
authors.forename: Warren E
authors.initials: WE
authors.lastname: Rose
authors.forename: Jens C
authors.initials: JC
authors.lastname: Eickhoff
authors.forename: Sanjay K
authors.initials: SK
authors.lastname: Shukla
authors.forename: Madhulatha
authors.initials: M
authors.lastname: Pantrangi
authors.forename: Suzan
authors.initials: S
authors.lastname: Rooijakkers
authors.forename: Sara E
authors.initials: SE
authors.lastname: Cosgrove
authors.forename: Victor
authors.initials: V
authors.lastname: Nizet
authors.forename: George
authors.initials: G
authors.lastname: Sakoulas
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D016470:Bacteremia / Q000276:immunology / Q000401:mortality*; D015415:Biomarkers; D015938:Complement Membrane Attack Complex / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006760:Hospitalization; D006801:Humans; D016753:Interleukin-10 / Q000097:blood*; D053583:Interleukin-1beta / Q000097:blood; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000276:immunology / Q000401:mortality*; D013211:Staphylococcus aureus / Q000235:genetics* / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000097:blood; D055815:Young Adult
chemical_list: D015415:Biomarkers; D015938:Complement Membrane Attack Complex; D053583:Interleukin-1beta; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10