Short Communication For reprint orders, please contact: reprints@futuremedicine.com Endothelial biomarkers in the light of new sepsis defnition Dunja Mihajlovic* ,1 , Snezana Brkic 2 , Dajana Lendak 2 , Aleksandra Novakov Mikic 3 , Biljana Draskovic 4 & Gorana Mitic 5 1 Faculty of Medicine, University of Novi Sad, Clinical Center of Vojvodina, Emergency Center, Novi Sad, Serbia 2 Faculty of Medicine, University of Novi Sad, Clinical Center of Vojvodina, Clinic for Infectious Diseases, Novi Sad, Serbia 3 Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia 4 Faculty of Medicine, University of Novi Sad, Institute of Child & Adolescent Health Care of Vojvodina, Clinic of Pediatric Surgery, Novi Sad, Serbia 5 Faculty of Medicine, Department of Hematology, Hemostasis, & Prevention of Thrombosis, University of Novi Sad, Clinical Center of Vojvodina, Laboratory Medicine Center, Novi Sad, Serbia *Author for correspondence: Tel.: +38 164 033 3820, +38 164 806 9105; dunja.mihajlovic@mf.uns.ac.rs Aim: The aim of our study was to compare usefulness of endothelial biomarkers for severity and outcome prediction in patients with positive Sepsis-3 criteria with traditionally used biomarkers. Methods: A total of 150 patients were included in our study. Patients were divided into two groups: patients with sepsis and those with infectious systemic infammatory response syndrome. Development of septic shock and 28- day mortality were assessed. Results: Endocan and thrombomodulin showed better discriminative power than procalcitonin for the presence of sepsis. Endocan showed good discriminative power for septic shock prediction. Addition of endocan signifcantly contributed to sequential (sepsis-related) organ failure as- sessment score in logistic regression model. Conclusion: Endothelial biomarkers have a good diagnostic potential for sepsis. Endocan is useful as a predictor of the severity and fatality of sepsis. First draft submitted: 16 August 2018; Accepted for publication: 30 January 2019; Published online: 28 March 2019 Keywords: endothelium • sepsis • shock Inadequate specificity and sensitivity of the systemic inflammatory response syndrome (SIRS) criteria as the part of the sepsis recognition pattern have led to development of a new concept of sepsis definition. This new concept brought to light organ dysfunction estimated with sequential (sepsis-related) organ failure assessment (SOFA) score and quick SOFA score (qSOFA) caused by infection as the corner stone of identification of septic patients [1,2]. Endothelium plays a pivotal role in major pathways involved in the pathogenesis of sepsis [3–7]. Identification of the extent of endothelial activation will most likely be important in therapeutic decision making with endothelium as one of the most important ‘organ system’ that should be targeted [6,8,9]. Besides biomarkers of endothelial activation which are easily accessible, such as von Willebrand factor (vWF) antigen and activity, research has brought attention to specific endothelium activation biomarkers, like endocan [10–17]. Proinflammatory cytokines like TNF-α and IL-1β promote synthesis and release of this molecule [14–17]. Endocan concentration is related to dysfunction of endothelium during systemic inflammation evoked by experimental endotoxemia and it is considered as a specific biomarker of endothelial activation in sepsis which shows very good diagnostic and prognostic capacity [14–17]. However, this molecule is still not used in every day clinical practice. Also, some biomarkers that can be detected due to endothelial activation in sepsis, such as thrombomodulin, are considered as relevant mediators, and are potential therapeutic agents [6,9,18–20]. Relationship between concentration of endothelial biomarkers like endocan and thrombomodulin with sepsis severity has been established based on the old sepsis definitions (Sepsis-1 and -2 criteria), which included the patients with infectious SIRS. In research regarding this subject, it was found that levels of endocan and thrombomodulin were increased in patients with organ failure [14,17–19]. However, new sepsis definition (Sepsis-3) excludes patients without organ failure from being septic. Thus, we wanted to re-evaluate diagnostic and prognostic potential of Biomark. Med. (Epub ahead of print) ISSN 1752-0363 10.2217/bmm-2018-0282 C  2019 Future Medicine Ltd