Gut barrier protein levels in serial blood samples from critically ill trauma patients during and after intensive care unit stay

Purpose In an efort to better manage critically ill patients hospitalised in the intensive care unit (ICU) after experiencing multiple traumas, the present study aimed to assess whether plasma levels of intestinal epithelial cell barrier proteins, including occludin, claudin-1, junctional adhesion molecule (JAM-1), tricellulin and zonulin, could be used as novel biomarkers. Additional potential markers such as intestinal fatty acid-binding protein (I-FABP), d-lactate, lipopolysaccharide (LPS) and citrulline were also evaluated. We also aimed to determine the possible relationships between the clinical, laboratory, and nutritional status of patients and the measured marker levels. Methods Plasma samples from 29 patients (frst, second, ffth and tenth days in the ICU and on days 7, 30 and 60 after hospital discharge) and 23 controls were subjected to commercial enzyme-linked immunosorbent assay (ELISA) testing. Results On frst day (admission) and on the second day, plasma I-FABP, d-lactate, citrulline, occludin, claudin-1, tricellulin and zonulin levels were high in trauma patients and positively correlated with lactate, C-reactive protein (CRP), number of days of ICU hospitalisation, Acute Physiology and Chronic Health Evaluation II (APACHE II) score and daily Sequential Organ Failure Assessment (SOFA) scores (P<0.05–P<0.01). Conclusion The results of the present study showed that occludin, claudin-1, tricellulin and zonulin proteins, as well as I-FABP, d-lactate and citrulline, may be used as promising biomarkers for the evaluation of disease severity in critically ill trauma patients, despite the complexity of the analysis of various barrier markers. However, our results should be supported by future studies.