Meta-analyses of diagnostic tests in infectious diseases: how helpful are they in the intensive care setting?

In acute-care settings timely and accurate diagnostic tools are critical for patient treatment decisions and outcomes. This review provides an up-to-date look at the meta-analyses of diagnostic test for infections in the ICU setting. There have been 3 meta-analyses investigating the value of procalcitonin as diagnostic marker of sepsis: overall, the performance of procalcitonin test was found moderate-good. Two meta-analyses evaluated methods for diagnosing intravascular device-related bloodstream infections. In general, quantitative catheter segment culture and paired quantitative blood culture showed reliable diagnostic yield, though significant heterogeneity was observed among studies. Criteria of diagnosing VAP in the intensive care unit has been evaluated in 3 systematic reviews. Overall, the cumulative results cast doubts about the usefulness of bacteriological data and quantitative cultures in the diagnosis of VAP; moreover, 2 of these meta-analyses concluded that invasive strategies for VAP diagnosis do not affect mortality.