Cardiovascular Insufficiency, Abdominal Sepsis, and Patients' Age Are Associated with Decreased Paraoxonase-1 (PON1) Activity in Critically Ill Patients with Multiple Organ Dysfunction Syndrome (MODS).

Oxidative stress and uncontrolled inflammation are hallmarks of sepsis, leading to organ failure and death. As demonstrated in animal studies, oxidative stress can be alleviated by antioxidant therapies. Paraoxonase-1 (PON1) is a serum-based antioxidant, anti-inflammatory agent, detoxifier, and quorum-sensing factor found to be a prognostic marker in sepsis. However, its associations with multiple organ dysfunction syndrome (MODS), a complication of sepsis and the leading cause of death in the surgical intensive care units (ICU), as well as with specific organ dysfunction, infection site, and invading pathogen remain unknown. Therefore, we measured arylesterase activity of PON1 in 87 individuals (35 with MODS) and related it to the clinical type, organ failure, infection site, pathogens, and hematological and biochemical indices of inflammation at admission to ICU and during a five-day follow-up. Suitability of PON1 and its indices derived from a follow-up as biomarkers in MODS was evaluated as well. MODS was associated with decreased PON1, more so in patients with septic shock, displaying an excellent accuracy as a marker of MODS (91%) and a fair one as a marker in differentiating septic shock from severe sepsis (76%). Decreased admission PON1 accompanied cardiovascular insufficiency (CVI), and, as its marker, PON1 displayed a good accuracy (82%). It was also associated with the abdomen as a site of infection but not with an invading pathogen. In multivariate analysis, 50% of variability in PON1 activity in patients with MODS was explained by the patients' age, CVI, and abdomen as a site of infection. Patients with septic shock, CVI, and abdominal MODS had distinctly different dynamics of PON1 during a follow-up. Mean PON1 activity during the follow-up reflected the associations observed for admission PON1 but was also significantly associated with metabolic dysfunction. Our results show PON1 potential as a biomarker in MODS, particularly as an indicator of CVI.