The role of Endocan as a Prognostic Biomarker in community-acquired pneumonia

Objective: The aim of this study was to determine the importance of using endocan as a biomarker in deciding the setting of treatment and predicting prognosis in patients with community-acquired pneumonia (CAP). Methods: This prospective, case-control study was conducted at Okmeydani Training and Research Hospital between November 20, 2016 to March 20th 2017. Blood samples were obtained from 63 patients who were admitted to internal medicine clinic due to CAP and 25 volunteers without active infection. Serum samples were centrifuged at 1000G for 15 minutes and stored at -20 degrees C. Samples were analyzed using human ESM1 (endocan) (Lot No: AK0017MAR0830) (Elabscience, Texas, USA) kit with Robonik (Mumbai, India) ELISA Plate Reader and Washer. Demographic and clinical data of the patients were recorded. CURB-65, qSOFA and Pneumonia Severity Index (PSI) scores were calculated. Primary endpoint of the study was 30-days mortality. Results: Mean serum endocan levels of the study group and the control group were 30.99 +/- 3.3 pg/ml and 246.5 +/- 49.95pg/ml, respectively. The difference between groups was statistically significant (p<0.005). 30-days mortality rate was 12.7% with eight patients, three of which died subsequently in the ICU. When patients were classified according to PSI and CURB-65 scores, endocan levels of PSI class >= 4 and CURB-65 >= 2 individuals were found to be significantly different than the control group. ROC analysis showed that serum endocan levels less than 64.96pg/ml has 85.2% sensitivity and 83.3% specificity for PSI class and 82.4% sensitivity and 55.6% specificity for CURB-65 score >= 2. Conclusion: Serum endocan levels are significantly lower in patients with community-acquired pneumonia than the control group.