title: Inflammatory cytokine measurement quickly discriminates gram-negative from gram-positive bacteremia in pediatric hematology/oncology patients with septic shock.
abstract: OBJECTIVE
  We performed a prospective study to evaluate the ability of inflammatory cytokines in discriminating gram-negative from gram-positive bacteremia in septic shock.
  
  
  METHODS
  During the study period, the serum inflammatory cytokine levels were measured at the onset of septic shock by flow cytometry in pediatric hematology/oncology patients with septic shock.
  
  
  RESULTS
  One hundred episodes of septic shock were enrolled. Of 97 episodes of monomicrobial infection, 73.2 % were caused by gram-negative bacteremia and 26.8 % by gram-positive bacteremia. Interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-α were closely related to the pediatric index of mortality 2 (PIM2) score and mortality. However, although the PIM2 score and mortality were comparable, the IL-6, IL-10, and TNF-α levels were significantly higher in patients with gram-negative bacteremia (GNB) than those with gram-positive bacteremia (median levels, pg/mL: IL-6: 784.1 vs. 254.4, P = 0.001; IL-10: 192.2 vs. 19.7, P < 0.001; TNF-α: 4.2 vs. 2.0, P < 0.001). Of the three cytokines, IL-10 was the most useful biomarker for GNB prediction in the derivation cohort and a cutoff value of 50 pg/mL showed a sensitivity of 70.8 % and a specificity of 80.0 %, with a positive predictive value of 89.5 %. When this cutoff value was applied to the validation cohort, the sensitivity, specificity, and positive predictive value were 80.9, 75.0, and 90.5 %, respectively.
  
  
  CONCLUSIONS
  Flow cytometry-based inflammatory cytokine measurement is a helpful adjuvant approach for early and quick discrimination of gram-negative from gram-positive bacteremia in pediatric hematology/oncology patients with septic shock which might be useful for evaluating the severity of shock and the selection and/or timely withdrawal or switch of antibiotics.
authors.affiliation: Division of Hematology-Oncology, Children's Hospital of Zhejiang University School of Medicine, Hangzhou 310003, People's Republic of China.
authors.forename: Xiao-Jun
authors.initials: XJ
authors.lastname: Xu
authors.forename: Yong-Min
authors.initials: YM
authors.lastname: Tang
authors.forename: Chan
authors.initials: C
authors.lastname: Liao
authors.forename: Hua
authors.initials: H
authors.lastname: Song
authors.forename: Shi-Long
authors.initials: SL
authors.lastname: Yang
authors.forename: Wei-Qun
authors.initials: WQ
authors.lastname: Xu
authors.forename: Shu-Wen
authors.initials: SW
authors.lastname: Shi
authors.forename: Ning
authors.initials: N
authors.lastname: Zhao
mesh_terms: D000293:Adolescent; D016470:Bacteremia / Q000097:blood* / Q000150:complications / Q000175:diagnosis*; D002648:Child; D002675:Child, Preschool; D016207:Cytokines / Q000097:blood*; D003937:Diagnosis, Differential; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000097:blood* / Q000150:complications / Q000175:diagnosis*; D016908:Gram-Positive Bacterial Infections / Q000097:blood* / Q000150:complications / Q000175:diagnosis*; D006402:Hematologic Diseases / Q000097:blood / Q000150:complications; D006801:Humans; D007223:Infant; D008297:Male; D009369:Neoplasms / Q000097:blood / Q000150:complications; D011446:Prospective Studies; D012720:Severity of Illness Index; D012772:Shock, Septic / Q000097:blood / Q000150:complications; D013997:Time Factors
chemical_list: D016207:Cytokines