Neutrophil extracellular traps (NETs), transfusion requirements and clinical outcomes in orthotopic liver transplantation.

Inflammatory phenomena have a direct impact on the prognosis of orthotopic liver transplantation (OLT). Neutrophil extracellular traps (NETs) contribute to OLT inflammation and hemostasis imbalance in OLT. The association between NETosis, clinical outcomes and transfusion requirements is not determined. To evaluate NETs release during OLT and the effect of NETosis ontransfusion requirements and adverse outcomes in a prospective cohort of patients submitted to OLT. We quantified citrullinated histones (cit-H3) and circulating-free-DNA (cf-DNA) in ninety-three patients submitted to OLT in three periods: pre-transplant, after graft reperfusion and before discharge. NETs markers were compared between these periods using ANOVA test. The association of NETosis and adverse outcomes was evaluated using regression models adjusted for age, sex and corrected MELD. We observed a peak of circulating NETs following reperfusion, evidenced by a 2.4-fold increase in cit-H3 levels in the post-graft reperfusion period (median levels of cit-H3 pre transplant: 0.5 ng/mL, after reperfusion: 1.2 ng/mL and at discharge 0.5 ng/mL, p < 0.0001). We observed an association between increased levels of cit-H3 and in-hospital death (OR = 1.168, 95% CI 1.021-1.336, p = 0.024). No association was found between NETs markers and transfusion requirements. There is a prompt release of NETs after reperfusion that is associated with poorer outcomes and death. Intraoperative NETs release seems to be independent of transfusion requirements. These findings highlight the relevance of inflammation promoted by NETS and its impact on OLT adverse clinical outcomes.

Association between plasmatic oxidative stress and thrombosis in primary antiphospholipid syndrome.

Antiphospholipid antibodies induce a pro-inflammatory and hypercoagulable state that lead to increased risk of thrombosis. Whether oxidative damage contributes thrombosis risk is a matter of debate. We evaluated the association between oxidative stress and thrombosis in primary antiphospholipid syndrome (t-PAPS). Plasma total antioxidant capacity and the levels of malondialdehyde (TBARs), carbonyl protein, and 8-isoprostane in plasma were determined in a group of patients with t-PAPS and in individuals without a history of thrombosis (controls) using commercial ELISA assays. The levels of these plasma markers of oxidative stress were compared between t-PAPS and controls using Mann-Whitney test. A total of 70 patients with t-PAPS and 74 controls were included. Overall, measurements of all plasma oxidative stress markers were similar between t-PAPS patients and controls. In a subgroup analysis, patients with t-PAPS and arterial thrombosis had a higher antioxidant capacity as compared to controls. Thrombotic PAPS was not associated with increased levels of oxidative stress markers, in comparison with individuals without thrombosis. Even though it is not possible to rule out that a mild oxidative damage, not detected by plasma markers, occurs in t-PAPS, our results suggest that measuring plasma oxidative stress markers has limited clinical relevance in t-PAPS.