Diagnostic Value of sTREM-1 in Bronchoalveolar Lavage Fluid in ICU Patients With Bacterial Lung Infections: A Bivariate Meta-Analysis

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.