Iwase S, et al. - The diagnostic accuracy of serum interleukin (IL)-6 levels for the diagnosis of infection was investigated in critically ill patients. The PubMed, MEDLINE, Cochrane Resister of Controlled Trials, Cochrane Database of Systematic Reviews, CINAHL, and Igaku Chuo Zasshi databases were searched for studies published from 1986 to August 2016 that evaluated the accuracy of IL-6 levels for the diagnosis of infection. Findings revealed a moderate diagnostic value and a potential clinical utility of blood levels of IL-6 in differentiating infection in critically ill patients with suspected infection.