{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T11:10:17Z","timestamp":1790680217179,"version":"4.1.0"},"reference-count":48,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,2,23]],"date-time":"2021-02-23T00:00:00Z","timestamp":1614038400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Med."],"abstract":"<jats:p><jats:bold>Background:<\/jats:bold> Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a poorly understood disease involving a high inflammatory status. Neutrophil extracellular traps (NETs) have been described as a new pathway to contain infectious diseases but can also participate in the imbalance of the inflammatory and the coagulation systems. NETs could be a therapeutic target in COVID-19 patients.<\/jats:p><jats:p><jats:bold>Methods:<\/jats:bold> Consecutive patients with SARS-CoV2 related pneumonia admitted to the intensive care unit were included in a prospective bicentric study. Neutrophil extracellular trap concentrations were quantified in whole blood samples at day-1 and day-3 by flow cytometry. The primary outcome was the association between the blood NET quantification at ICU admission and the number of days with refractory hypoxemia defined by a PaO<jats:sub>2<\/jats:sub>\/FIO<jats:sub>2<\/jats:sub> ratio \u2264100 mmHg.<\/jats:p><jats:p><jats:bold>Results:<\/jats:bold> Among 181 patients admitted to the ICUs for acute respiratory failure related to SARS-CoV2 pneumonia, 58 were included in the analysis. Patients were 62 [54, 69] years old in median, mostly male (75.9%). The median number of days with severe hypoxemia was 4 [2, 6] days and day-28 mortality was 27.6% (<jats:italic>n<\/jats:italic> = 16). The blood level of NETs significantly decreased between day-1 and day-3 in patients who survived (59.5 [30.5, 116.6] to 47 [33.2, 62.4] <jats:italic>p<\/jats:italic> = 0.006; 8.6 [3.4, 18.0] to 4 [1.4, 10.7] <jats:italic>p<\/jats:italic> = 0.001 and 7.4 [4.0, 16.7] to 2.6 [1.0, 8.3] <jats:italic>p<\/jats:italic> = 0.001 for MPO+, Cit-H3+, and MPO+ Cit-H3+ NETs, respectively) while it remained stable in patients who died (38.4 [26.0, 54.8] to 44.5 [36.4, 77.7] <jats:italic>p<\/jats:italic> = 0.542; 4.9 [1.3, 13.0] to 5.5 [2.8, 6.9] <jats:italic>p<\/jats:italic> = 0.839 and 4 [1.3, 13.6] to 2.7 [1.4, 4.5] <jats:italic>p<\/jats:italic> = 0.421 for MPO+, Cit-H3+, and MPO+ Cit-H3+ NETs, respectively). In multivariable negative binomial regression, the blood level of MPO+ NETs was negatively associated with the number of days with severe hypoxemia within 7 days (0.84 [0.73, 0.97]), while neither Cit-H3+ NETs nor double-positive NETs were significantly associated with the primary outcome.<\/jats:p><jats:p><jats:bold>Conclusion:<\/jats:bold> The whole blood level of NETs at day-1 was negatively associated with the number of days with severe hypoxemia in patients admitted to the intensive care unit for SARS-CoV2 related pneumonia. The lack of decrease of the blood level of NETs between day-1 and day-3 discriminated patients who died within day-28.<\/jats:p>","DOI":"10.3389\/fmed.2021.615984","type":"journal-article","created":{"date-parts":[[2021,2,23]],"date-time":"2021-02-23T05:37:29Z","timestamp":1614058649000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":23,"title":["Neutrophil Extracellular Traps in SARS-CoV2 Related Pneumonia in ICU Patients: The NETCOV2 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