{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T09:52:14Z","timestamp":1791453134749,"version":"4.3.3"},"reference-count":19,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T00:00:00Z","timestamp":1760054400000},"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:sec><jats:title>Background<\/jats:title><jats:p>Thrombocytopenia has been associated with poor outcomes in various infectious diseases, including COVID-19. This study investigates the relationship between platelet (PLT) count at hospital admission and clinical characteristics, treatments, and outcomes in patients with COVID-19 pneumonia.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>We retrospectively analyzed 797 patients hospitalized for COVID-19 pneumonia, stratifying them into three groups by platelet count: &amp;lt;150,000\/mm<jats:sup>3<\/jats:sup> (22%), 150,000\u2013400,000\/mm<jats:sup>3<\/jats:sup> (76%), and &amp;gt;400,000\/mm<jats:sup>3<\/jats:sup> (2.5%).<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>Patients with PLT\u202f&amp;lt;\u202f150,000\/mm<jats:sup>3<\/jats:sup>, more frequently male, and had a higher prevalence of cirrhosis and fibrosis. They presented less severe respiratory impairment and lower inflammatory markers. They also showed lower use of enoxaparin and a higher use of fondaparinux. Mortality was at the limits of significance in this group (37% vs. 28 and 20%, <jats:italic>p<\/jats:italic>\u202f=\u202f0.056), and thrombocytopenia was independently associated with increased risk of in-hospital death (HR 1.483, 95% CI 1.023\u20132.150; <jats:italic>p<\/jats:italic>\u202f=\u202f0.037).<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusion<\/jats:title><jats:p>Thrombocytopenia on admission independently predicts mortality in patients hospitalized with COVID-19 pneumonia.<\/jats:p><\/jats:sec>","DOI":"10.3389\/fmed.2025.1614447","type":"journal-article","created":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T05:28:15Z","timestamp":1760074095000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":5,"title":["Platelet count and clinical outcomes in hospitalized patients with COVID-19 pneumonia"],"prefix":"10.3389","volume":"12","author":[{"given":"Carmine","family":"Siniscalchi","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pierpaolo","family":"Di 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