title: Diagnostic value of sTREM-1 in bronchoalveolar lavage fluid in ICU patients with bacterial lung infections: a bivariate meta-analysis.
abstract: BACKGROUND
  The serum soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) is a useful biomarker in differentiating bacterial infections from others. However, the diagnostic value of sTREM-1 in bronchoalveolar lavage fluid (BALF) in lung infections has not been well established. We performed a meta-analysis to assess the accuracy of sTREM-1 in BALF for diagnosis of bacterial lung infections in intensive care unit (ICU) patients.
  
  
  METHODS
  We searched PUBMED, EMBASE and Web of Knowledge (from January 1966 to October 2012) databases for relevant studies that reported diagnostic accuracy data of BALF sTREM-1 in the diagnosis of bacterial lung infections in ICU patients. Pooled sensitivity, specificity, and positive and negative likelihood ratios were calculated by a bivariate regression analysis. Measures of accuracy and Q point value (Q*) were calculated using summary receiver operating characteristic (SROC) curve. The potential between-studies heterogeneity was explored by subgroup analysis.
  
  
  RESULTS
  Nine studies were included in the present meta-analysis. Overall, the prevalence was 50.6%; the sensitivity was 0.87 (95% confidence interval (CI), 0.72-0.95); the specificity was 0.79 (95% CI, 0.56-0.92); the positive likelihood ratio (PLR) was 4.18 (95% CI, 1.78-9.86); the negative likelihood ratio (NLR) was 0.16 (95% CI, 0.07-0.36), and the diagnostic odds ratio (DOR) was 25.60 (95% CI, 7.28-89.93). The area under the SROC curve was 0.91 (95% CI, 0.88-0.93), with a Q* of 0.83. Subgroup analysis showed that the assay method and cutoff value influenced the diagnostic accuracy of sTREM-1.
  
  
  CONCLUSIONS
  BALF sTREM-1 is a useful biomarker of bacterial lung infections in ICU patients. Further studies are needed to confirm the optimized cutoff value.
authors.affiliation: Department of Respiratory Medicine, Lianyungang First People's Hospital, Affiliated Hospital of Xuzhou Medical College, Lianyungang, China. shijiaxin919@126.com
authors.forename: Jia-Xin
authors.initials: JX
authors.lastname: Shi
authors.forename: Jia-Shu
authors.initials: JS
authors.lastname: Li
authors.forename: Rong
authors.initials: R
authors.lastname: Hu
authors.forename: Chun-Hua
authors.initials: CH
authors.lastname: Li
authors.forename: Yan
authors.initials: Y
authors.lastname: Wen
authors.forename: Hong
authors.initials: H
authors.lastname: Zheng
authors.forename: Feng
authors.initials: F
authors.lastname: Zhang
authors.forename: Qin
authors.initials: Q
authors.lastname: Li
mesh_terms: D001424:Bacterial Infections / Q000175:diagnosis / Q000378:metabolism*; D015415:Biomarkers / Q000032:analysis; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry*; D006801:Humans; D007362:Intensive Care Units; D008171:Lung Diseases / Q000175:diagnosis / Q000378:metabolism* / Q000382:microbiology; D008562:Membrane Glycoproteins / Q000032:analysis*; D012372:ROC Curve; D011971:Receptors, Immunologic / Q000032:analysis*; D000073871:Triggering Receptor Expressed on Myeloid Cells-1
chemical_list: D015415:Biomarkers; D008562:Membrane Glycoproteins; D011971:Receptors, Immunologic; C408842:TREM1 protein, human; D000073871:Triggering Receptor Expressed on Myeloid Cells-1