Role of procalcitonin in the diagnosis of infective endocarditis: a meta-analysis

Background: Infective endocarditis (IE) is a diagnostic challenge. We aimed to systemically summarize the current evidence on the diagnostic value of procalcitonin (PCT) in identifying IE. Methods: We searched EMBASE, MEDLINE, Cochrane database, and reference lists of relevant articles with no language restrictions through September 2012 and selected studies that reported the diagnostic performance of PCT alone or compare with other biomarkers to diagnose IE. We summarized test performance characteristics with the use of forest plots, hierarchical summary receiver operating characteristic curves, and bivariate random effects models. Results: We found 6 qualifying studies that included 1006 episodes of suspected infection with 216 (21.5%) confirmed IE episodes from 5 countries. Bivariate pooled sensitivity, specificity, positive likelihood ratios, and negative likelihood ratios were 64% (95% confidence interval [CI], 52%-74%), 73% (95% CI 58%-84%), 2.35 (95% CI 1.40-3.95), and 0.50 (95% CI 0.35-0.70), respectively. Of the 5 studies examining C-reactive protein (CRP), the pooled sensitivity, specificity, positive likelihood ratios, and negative likelihood ratios were 75%(95% CI 62%-85%), 73% (95% CI 61%-82%), 2.81 (95% CI 1.70-4.65), and 0.34 (95% CI 0.19-0.60), respectively. The global measures of accuracy, area under the receiver operating characteristic curve (AUC) and diagnostic odds ratio (dOR), showed CRP (AUC 0.80, dOR 8.55) may have higher accuracy than PCT (AUC 0.71, dOR 4.67) in diagnosing IE. Conclusions: Current evidence does not support the routine use of serum PCT or CRP to rule in or rule out IE in patients suspected to have IE. (C) 2013 Elsevier Inc. All rights reserved.