{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,8]],"date-time":"2026-04-08T17:01:08Z","timestamp":1775667668098,"version":"3.50.1"},"reference-count":37,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,8,25]],"date-time":"2021-08-25T00:00:00Z","timestamp":1629849600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antioxidants"],"abstract":"<jats:p>Since SARS-CoV-2 emerged in 2019, strict monitoring of post-COVID-19 patients in order to ensure the early detection of sequelae and\/or chronic organ damage that could been associated with the infection has been essential. Potential involvement of the NO pathway in the development of post-COVID-19 lung fibrotic alterations is feasible, since the majority of respiratory cells can produce NO, and fractional exhaled NO (FeNO) represents a biomarker of airway inflammation. The aim of this study was to investigate the potential utility of multiple-flow FeNO parameters in a post-COVID-19 population and to compare it with other indicators of lung damage proposed in the literature. We enrolled 20 patients hospitalized for COVID-19, who underwent clinical, respiratory functional (including PFTs and FeNO) and radiological follow-up after discharge. Compared with age- and sex-matched healthy controls, post-COVID-19 patients showed significantly higher FeNO 350 mL\/s and CaNO levels. Moreover, among the parameters included in the follow-up, CaNO showed the best accuracy in indicating predominant fibrotic changes and GGO at CT scan. To our knowledge, this preliminary study has investigated for the first time multiple-flow FeNO parameters in a post-COVID-19 population. The evidence of increased CaNO values may imply the persistence of alveolar and bronchiolar inflammation and\/or a mild impairment of the alveolar-capillary membrane in these patients.<\/jats:p>","DOI":"10.3390\/antiox10091350","type":"journal-article","created":{"date-parts":[[2021,8,26]],"date-time":"2021-08-26T00:19:26Z","timestamp":1629937166000},"page":"1350","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Alveolar Nitric Oxide as a Biomarker of COVID-19 Lung Sequelae: A Pivotal Study"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8639-2882","authenticated-orcid":false,"given":"Paolo","family":"Cameli","sequence":"first","affiliation":[{"name":"Respiratory Diseases Unit, Department of Medical Sciences, Siena University Hospital, 53100 Siena, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elena","family":"Bargagli","sequence":"additional","affiliation":[{"name":"Respiratory Diseases Unit, Department of Medical Sciences, Siena University Hospital, 53100 Siena, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1118-3223","authenticated-orcid":false,"given":"Laura","family":"Bergantini","sequence":"additional","affiliation":[{"name":"Respiratory Diseases Unit, Department of Medical Sciences, Siena University Hospital, 53100 Siena, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2368-5722","authenticated-orcid":false,"given":"Miriana","family":"d\u2019Alessandro","sequence":"additional","affiliation":[{"name":"Respiratory Diseases Unit, Department of Medical Sciences, Siena University Hospital, 53100 Siena, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bruna","family":"Giugno","sequence":"additional","affiliation":[{"name":"Respiratory Diseases Unit, Department of Medical Sciences, Siena University Hospital, 53100 Siena, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Francesco","family":"Gentili","sequence":"additional","affiliation":[{"name":"Unit of Diagnostic Imaging, University Hospital Santa Maria alle Scotte, 53100 Siena, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Piersante","family":"Sestini","sequence":"additional","affiliation":[{"name":"Respiratory Diseases Unit, Department of Medical Sciences, Siena University Hospital, 53100 Siena, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,25]]},"reference":[{"key":"ref_1","unstructured":"WHO (2021, July 17). 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