Critical illness causes disturbances in lipid metabolism. Here, we investigated the levels of apolipoprotein A-IV (apoA-IV), a regulator of triglyceride and cholesterol metabolism, in human sepsis. ApoA-IV (analyzed in 156 patients with systemic inflammatory response syndrome (SIRS)/sepsis) and cholesteryl ester (CE) (analyzed in 121 of these patients) were lower in patients compared to 43 healthy controls. In contrast, triglyceride (TG) levels were elevated in patients. ApoA-IV levels in plasma of the patients did not correlate with these lipids. Patients with SIRS, sepsis or septic shock had comparable apoA-IV, TG, CE and free cholesterol (FC) levels. Patients on dialysis had significantly lower CE levels, whereas apoA-IV levels did not change much. CE levels were elevated in patients with viral sepsis due to SARS-CoV-2 infection in comparison to SIRS/sepsis patients not infected by this virus. CE levels correlated negatively with procalcitonin, interleukin-6 and bilirubin, while TGs were positively associated with bilirubin and C-reactive protein. ApoA-IV, TG, CE and FC levels were not associated with bacterial infection or survival. In conclusion, this analysis suggests that CE levels decline in sepsis-related renal failure and also shows that plasma apoA-IV and CE levels are early biomarkers of sepsis.

Background/Objectives: Interleukin-32 (IL-32) is a pro-inflammatory cytokine primarily produced by immune cells and involved in bacterial and viral infections. This study investigates whether plasma IL-32 is associated with sepsis severity and clinical outcomes. Methods: Plasma IL-32 levels were measured in 186 patients with systemic inflammatory response syndrome (SIRS), sepsis, or septic shock, as well as in 40 controls. The relationship between IL-32 levels and SARS-CoV-2 or bacterial infections, alongside underlying etiological conditions, was assessed. Results: Patients with liver cirrhosis exhibited elevated plasma IL-32 levels. After excluding these patients, IL-32 levels were lower in SIRS/sepsis patients compared to the controls. No significant differences in IL-32 levels were observed among SIRS, sepsis, and septic shock patients. Additionally, underlying conditions such as pancreatitis and cholangitis did not influence IL-32 levels. Patients with bloodstream bacterial infections, SARS-CoV-2 infections, or no documented infection had comparable IL-32 levels. Notably, higher IL-32 levels were associated with increased mortality. Conclusions: These findings suggest that a reduction in plasma IL-32 levels may be protective in SIRS/sepsis patients, as elevated levels are linked to poor survival outcomes.

Background/Objectives: Chemerin is an adipokine involved in inflammatory and metabolic diseases, and its circulating levels have been associated with inflammatory parameters in various patient cohorts. Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infection, which causes COVID-19, triggers inflammatory pathways. However, the association between serum chemerin levels and COVID-19 disease severity and outcomes has not been definitively established. Methods: In this study, serum chemerin levels were analyzed in 64 patients with moderate COVID-19 and 60 patients with severe disease. Results: The results showed that serum chemerin levels were comparable between these two groups and slightly higher than in healthy controls. Notably, COVID-19 patients with hypertension exhibited elevated serum chemerin levels, while those with liver cirrhosis had lower levels. When patients with these comorbidities were excluded from the analyses, serum chemerin levels in COVID-19 patients were similar to those in healthy controls. Positive correlations were observed between serum chemerin levels and markers such as alkaline phosphatase, C-reactive protein, eosinophils, and lymphocytes in the entire cohort, as well as in the subgroup excluding patients with hypertension and cirrhosis. Additionally, urinary chemerin levels were comparable between COVID-19 patients and controls, and neither hypertension nor dialysis significantly affected urinary chemerin levels. Both survivors and non-survivors had similar serum and urinary chemerin levels. Conclusions: In conclusion, this study suggests that comorbidities such as arterial hypertension and liver cirrhosis do have a more significant impact on serum chemerin levels than SARS-CoV-2 infection itself.