{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T04:14:18Z","timestamp":1791951258464,"version":"4.3.4"},"reference-count":90,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2023,1,12]],"date-time":"2023-01-12T00:00:00Z","timestamp":1673481600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Pneumonia is a growing problem worldwide and remains an important cause of morbidity, hospitalizations, intensive care unit admission and mortality. Viruses are the causative agents in almost a fourth of cases of community-acquired pneumonia (CAP) in adults, with an important representation of influenza virus and SARS-CoV-2 pneumonia. Moreover, mixed viral and bacterial pneumonia is common and a risk factor for severity of disease. It is critical for clinicians the early identification of the pathogen causing infection to avoid inappropriate antibiotics, as well as to predict clinical outcomes. It has been extensively reported that biomarkers could be useful for these purposes. This review describe current evidence and provide recommendations about the use of biomarkers in influenza and SARS-CoV-2 pneumonia, focusing mainly on procalcitonin (PCT) and C-reactive protein (CRP). Evidence was based on a qualitative analysis of the available scientific literature (meta-analyses, randomized controlled trials, observational studies and clinical guidelines). Both PCT and CRP levels provide valuable information about the prognosis of influenza and SARS-CoV-2 pneumonia. Additionally, PCT levels, considered along with other clinical, radiological and laboratory data, are useful for early diagnosis of mixed viral and bacterial CAP, allowing the proper management of the disease and adequate antibiotics prescription. The authors propose a practical PCT algorithm for clinical decision-making to guide antibiotic initiation in cases of influenza and SARS-CoV-2 pneumonia. Further well-design studies are needed to validate PCT algorithm among these patients and to confirm whether other biomarkers are indeed useful as diagnostic or prognostic tools in viral pneumonia.<\/jats:p>","DOI":"10.3390\/antibiotics12010161","type":"journal-article","created":{"date-parts":[[2023,1,12]],"date-time":"2023-01-12T05:45:33Z","timestamp":1673502333000},"page":"161","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["The Role of Biomarkers in Influenza and COVID-19 Community-Acquired Pneumonia in Adults"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8298-2228","authenticated-orcid":false,"given":"Raquel","family":"Carbonell","sequence":"first","affiliation":[{"name":"Critical Care Department, Hospital Universitari Joan XXIII, 43005 Tarragona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gerard","family":"Moreno","sequence":"additional","affiliation":[{"name":"Critical Care Department, Hospital Universitari Joan XXIII, 43005 Tarragona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5834-4063","authenticated-orcid":false,"given":"Ignacio","family":"Mart\u00edn-Loeches","sequence":"additional","affiliation":[{"name":"Department of Anaesthesia and Critical Care, St James\u2019s University Hospital, Trinity Centre for Health Sciences, Multidisciplinary Intensive Care Research Organization (MICRO), D08 NHY1 Dublin, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mar\u00eda","family":"Bod\u00ed","sequence":"additional","affiliation":[{"name":"Critical Care Department, Hospital Universitari Joan XXIII, URV\/IISPV\/CIBERES, 43005 Tarragona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alejandro","family":"Rodr\u00edguez","sequence":"additional","affiliation":[{"name":"Critical Care Department, Hospital Universitari Joan XXIII, URV\/IISPV\/CIBERES, 43005 Tarragona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2115","DOI":"10.1378\/chest.122.6.2115","article-title":"Epidemiology and Outcomes of Ventilator-Associated Pneumonia in a Large US Database","volume":"122","author":"Rello","year":"2002","journal-title":"Chest"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"273","DOI":"10.1097\/RTI.0000000000000343","article-title":"Clinical Approach to Community-acquired Pneumonia","volume":"33","year":"2018","journal-title":"J. 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