The role of TNF-α superfamily members in immunopathogenesis of sepsis.

BACKGROUND: Members of TNFα superfamily, A proliferation inducing ligand (APRIL), B-cell activating factor (BAFF) and Transmembrane activator and calcium cyclophylin interactor (TACI) are main regulators of B-cell function. The aim of this study was to evaluate concentrations of APRIL, BAFF and soluble TACI (sTACI) receptor in septic patients compared to healthy controls and compare concentrations of these biomarkers depending on sepsis severity and outcome. MATERIALS AND METHODS: A total of 115 septic patients and 30 healthy volunteers were included and concentrations of APRIL, BAFF and sTACI were determined in all subjects at the admission (ELISA R&D Systems tests). Concentrations of these biomarkers in function of sepsis severity (sepsis n = 94 and septic shock n = 21) and outcome (lethal n = 40, recovery n = 75) were tested, as well as correlations with APACHE II and SOFA scores, immunoglobulins, complement, PCT and CRP concentrations. RESULTS: Concentrations of all three biomarkers were significantly increased in septic patients compared to controls (AUCAPRIL = 0.982, AUCBAFF = 0.873, AUCsTACI = 0.683). Higher concentrations of APRIL and sTACI (p = 0.033, p = 0.037), and lower concentrations of BAFF (p = 0.005) were observed in patients with septic shock compared to sepsis. BAFF concentrations correlated positively with IgM, C3 and C4 levels. sTACI and APRIL were shown to be predictors of lethal outcome (p = 0.003, p = 0.049). CONCLUSIONS: Concentrations of observedTNFα superfamily members are significantly increased in septic patients, confirming their role in sepsis pathogenesis.Higher concentrations of anti-inflammatory sTACI receptor correlated with severity of sepsis and poorer prognosis, thus potentially indicating domination of anti-inflammatory response in septic patients with worse outcome.

APRIL and sTACI could be predictors of multiorgan dysfunction syndrome in sepsis.

Although the role of B cells in sepsis immunoregulation has become an interesting topic, there is lack of data on the role of B cell function regulators in prediction of multiorgan dysfunction syndrome (MODS). The aim of this study was to evaluate the prognostic value of A Proliferation Inducing Ligand (APRIL) and soluble Transmembrane Activator and CAML Interactor Protein (sTACI), the main B cell function regulators, in prediction of MODS development within the first 48 h after admission to intensive care unit, among septic patients. We included 112 patients with sepsis, treated at Clinic for Infectious Diseases and Emergency Center, Clinical Center of Vojvodina, Novi Sad, Serbia. Plasma concentrations of APRIL and sTACI were determined at the admission and potential development of MODS was confirmed in the first 48 h. Concentrations of APRIL (p = 0.003) and sTACI (p<0.001) were higher in patients who developed MODS (n = 30). ROC curve analysis showed that AUC for sTACI (AUC = 0.764) was greater than that for procalcitonin (AUC = 0.719) and APRIL (AUC = 0.673) in MODS development prediction. Multivariate regression analysis showed that sTACI, as an anti-inflammatory biomarker stimulating the apoptosis of B cells, was the only independent predictor of MODS, beside SOFA score. Elevated level of sTACI could be the alarm for the increased B cell apoptosis and development of immune paralysis. Including these biomarkers into predictive scores specific for septic patients may potentially improve their sensitivity and specificity. Measurement of their concentrations dynamics could contribute to better assessment of sepsis evolution and timely introduction of immunomodulatory therapy.

Thrombomodulin is a Strong Predictor of Multiorgan Dysfunction Syndrome in Patients With Sepsis.

BACKGROUND: Biomarkers of endothelial dysfunction are not recommended for routine laboratory investigation of the outcome prognosis and prediction of the course of sepsis. METHODS: A total of 60 patients who fulfilled the criteria for diagnosis of sepsis were included in our study. Development of multiorgan dysfunction syndrome (MODS) in the first 48 hours was assessed. Differences between groups of patients with sepsis were assessed by Mann-Whitney U test and by Kruskal-Wallis test. Logistic regression analysis was performed to test the joint effect of different predictors. RESULTS: Level of thrombomodulin was significantly higher in group of patients with MODS than without MODS (P = .015). Levels of antithrombin (P = .026) and protein C (P = .035) were significantly lower in patients with MODS. Level of thrombomodulin was the strongest predictor in MODS development in first 48 hours (P = .028). CONCLUSION: The level of thrombomodulin not only was able to distinguish the severity of sepsis but also was a significant predictor of MODS development.

Endocan is useful biomarker of survival and severity in sepsis.

INTRODUCTION: Coagulation abnormalities which occur as a consequence of endothelial changes are recognized as diagnostic criteria for sepsis, but significance of these changes in the outcome prognosis and prediction of the course of sepsis is still not accurately defined. MATERIALS AND METHODS: 60 patients who fulfilled the criteria for diagnosis of sepsis were included in our study. Patients were categorized in two groups according to sepsis severity and organ failure and MODS development was assessed in the first 48 h from ICU admission. Prothrombin time (PT), activated partial thromboplastin time (aPTT) and endothelial cell specific molecule-1(endocan) levels, as well as procalcitonin (PCT) and C-reactive protein (CRP) were determined within the first 24h of the onset of the disease. Predictive APACHE II (Acute Physiology and Chronic Health Evaluation II) and SOFA (Sequential Organ Failure Assessment) scores were calculated on the day of ICU admission. Data were used to determine an association between day 1 biomarker levels, organ dysfunction score values and the development of organ failure, multiple organ dysfunction syndrome (MODS), and mortality during 28 days. These connections were determined by plotting of receiver operating characteristic (ROC) curves. Differences between groups were assessed by Mann-Whitney U test. Categorical variables were compared using chi-square test. RESULTS: Concentration of endocan was significantly higher in the group of patients with sepsis induced organ failure, MODS development and in the group of non- survivors in contrast to group with less severe form of the disease, without multiorgan failure, and in contrast to group of survivors (p<0.05). Values of areas under the ROC curves showed that endocan levels had good discriminative power for more severe course of sepsis, MODS development and possible discriminative power for mortality prediction (AUC: 0.81, 0.67, 0.71 retrospectively), better than PCT for fatality (AUC:053) and better than APACHE II (AUC:0.55) and SOFA (AUC: 0.57) scores for organ failure. CONCLUSIONS: Results of our study show that endocan can be used as strong and significant predictor of sepsis severity and outcome, perhaps even better than SOFA and APACHE II scores.