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It points to increased liver fibrogenesis during acute COVID-19 with possible long-term consequences. This study aimed to assess liver fibrosis in COVID-19 patients by serum hyaluronic acid (HA) and FIB-4.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>The study included the acute COVID-19 group (66 patients, 50% females, mean age 58.3\u2009\u00b1\u200914.6), the post-COVID group (58 patients in 3\u20136\u00a0months after the recovery, 47% females, mean age 41.2\u2009\u00b1\u200913.4), and a control group (17 people, 47% females, mean age 42.8\u2009\u00b1\u200911.0). Ultrasound elastography was performed in the post-COVID and control groups.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Sixty-five percent of the acute COVID-19 group had increased FIB-4 (&gt;\u20091.45), and 38% of patients had FIB-4\u2009\u2265\u20093.25. After matching by demographics, 52% of acute COVID-19 and 5% of the post-COVID group had FIB-4\u2009&gt;\u20091.45, and 29% and 2% of patients had FIB-4\u2009\u2265\u20093.25, respectively. Increased serum HA (\u2265\u200975\u00a0ng\/ml) was observed in 54% of the acute COVID-19 and 15% of the post-COVID group. In the acute COVID-19 group, HA positively correlated with FIB-4, AST, ALT, LDH, IL-6, and ferritin and negatively with blood oxygen saturation. In the post-COVID group, HA did not correlate with FIB-4, but it was positively associated with higher liver stiffness and ALT.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>More than half of acute COVID-19 patients had increased serum HA and FIB-4 related to liver function tests, inflammatory markers, and blood oxygen saturation. It provides evidence for the induction of liver fibrosis by multiple factors during acute COVID-19. Findings also indicate possible liver fibrosis in about 5% of the post-COVID group.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1186\/s12876-021-01939-7","type":"journal-article","created":{"date-parts":[[2021,10,11]],"date-time":"2021-10-11T06:09:07Z","timestamp":1633932547000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":38,"title":["Intriguing findings of liver fibrosis following COVID-19"],"prefix":"10.1186","volume":"21","author":[{"given":"Oksana","family":"Kolesova","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ieva","family":"Vanaga","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sniedze","family":"Laivacuma","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aleksejs","family":"Derovs","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aleksandrs","family":"Kolesovs","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maija","family":"Radzina","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ardis","family":"Platkajis","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jelena","family":"Eglite","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elvira","family":"Hagina","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Seda","family":"Arutjunana","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Davis Simanis","family":"Putrins","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jelena","family":"Storozenko","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Baiba","family":"Rozentale","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ludmila","family":"Viksna","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2021,10,11]]},"reference":[{"issue":"1","key":"1939_CR1","doi-asserted-by":"publisher","first-page":"20","DOI":"10.1111\/liv.14730","volume":"41","author":"AD Nardo","year":"2021","unstructured":"Nardo AD, Schneeweiss-Gleixner M, Bakail M, et al. 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