{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T15:55:29Z","timestamp":1776873329040,"version":"3.51.2"},"reference-count":10,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2020,11,24]],"date-time":"2020-11-24T00:00:00Z","timestamp":1606176000000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2020,11,24]],"date-time":"2020-11-24T00:00:00Z","timestamp":1606176000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Respir Res"],"published-print":{"date-parts":[[2020,12]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec>\n<jats:title>Background<\/jats:title>\n<jats:p>Coronavirus disease COVID-19 has become a public health emergency of international concern. Together with the quest for an effective treatment, the question of the post-infectious evolution of affected patients in healing process remains uncertain. Krebs von den Lungen 6 (KL-6) is a high molecular weight mucin-like glycoprotein produced by type II pneumocytes and bronchial epithelial cells. Its production is raised during epithelial lesions and cellular regeneration. In COVID-19 infection, KL-6 serum levels could therefore be of interest for diagnosis, prognosis and therapeutic response evaluation.<\/jats:p>\n<\/jats:sec><jats:sec>\n<jats:title>Materials and methods<\/jats:title>\n<jats:p>Our study retrospectively compared KL-6 levels between a cohort of 83 COVID-19 infected patients and two other groups: healthy subjects (n\u2009=\u200970) on one hand, and a heterogenous group of patients suffering from interstitial lung diseases (n\u2009=\u200931; composed of 16 IPF, 4 sarcoidosis, 11 others) on the other hand. Demographical, clinical and laboratory indexes were collected. Our study aims to compare KL-6 levels between a COVID-19 population and healthy subjects or patients suffering from interstitial lung diseases (ILDs). Ultimately, we ought to determine whether KL-6 could be a marker of disease severity and bad prognosis.<\/jats:p>\n<\/jats:sec><jats:sec>\n<jats:title>Results<\/jats:title>\n<jats:p>Our results showed that serum KL-6 levels in COVID-19 patients were increased compared to healthy subjects, but to a lesser extent than in patients suffering from ILD. Increased levels of KL-6 in COVID-19 patients were associated with a more severe lung disease.<\/jats:p>\n<\/jats:sec><jats:sec>\n<jats:title>Discussion and conclusion<\/jats:title>\n<jats:p>Our results suggest that KL-6 could be a good biomarker to assess ILD severity in COVID-19 infection. Concerning the therapeutic response prediction, more studies are necessary.<\/jats:p>\n<\/jats:sec>","DOI":"10.1186\/s12931-020-01560-4","type":"journal-article","created":{"date-parts":[[2020,11,24]],"date-time":"2020-11-24T08:03:18Z","timestamp":1606204998000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Could KL-6 levels in COVID-19 help to predict lung disease?"],"prefix":"10.1186","volume":"21","author":[{"given":"AN","family":"Frix","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"L.","family":"Schoneveld","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"A.","family":"Ladang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"M.","family":"Henket","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"B.","family":"Duysinx","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"F.","family":"Vaillant","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"B.","family":"Misset","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"M.","family":"Moutschen","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"R.","family":"Louis","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"E.","family":"Cavalier","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J.","family":"Guiot","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2020,11,24]]},"reference":[{"key":"1560_CR1","unstructured":"WHO. Coronavirus disease (COVID-19) Pandemic [Internet]. 2020. https:\/\/www.who.int\/emergencies\/diseases\/novel-coronavirus-2019."},{"key":"1560_CR2","unstructured":"CDC. Coronavirus (COVID-19) [Internet]. 2020. https:\/\/www.cdc.gov\/coronavirus\/2019-ncov\/index.html."},{"issue":"12","key":"1560_CR3","doi-asserted-by":"publisher","first-page":"e00182-17","DOI":"10.1128\/JVI.00182-17","volume":"91","author":"T Venkataraman","year":"2017","unstructured":"Venkataraman T, Coleman CM, Frieman MB. Overactive epidermal growth factor receptor signaling leads to increased fibrosis after severe acute respiratory syndrome coronavirus infection. J Virol. 2017;91(12):e00182-17.","journal-title":"J Virol."},{"issue":"3","key":"1560_CR4","doi-asserted-by":"publisher","first-page":"273","DOI":"10.1007\/s00408-017-9993-5","volume":"195","author":"J Guiot","year":"2017","unstructured":"Guiot J, Moermans C, Henket M, Corhay J-L, Louis R. Blood biomarkers in idiopathic pulmonary fibrosis. 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Platelet\u2010to\u2010lymphocyte ratio is associated with prognosis in patients with Corona Virus Disease\u201019. J Med Virol. 2020.","DOI":"10.1002\/jmv.25767"},{"key":"1560_CR10","doi-asserted-by":"publisher","DOI":"10.1101\/2020.03.24.20040162","author":"Y Han","year":"2020","unstructured":"Han Y, Zhang H, Mu S, Wei W, Jin C, Xue Y, et al. Lactate dehydrogenase, a risk factor of severe COVID-19 patients. 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