{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T16:51:51Z","timestamp":1787331111658,"version":"build-2736575974"},"reference-count":35,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2023,4,28]],"date-time":"2023-04-28T00:00:00Z","timestamp":1682640000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Fondo de Investigaci\u00f3n en Salud of the Instituto de Salud Carlos III","award":["PI 14\/01898"],"award-info":[{"award-number":["PI 14\/01898"]}]},{"name":"Fondo de Investigaci\u00f3n en Salud of the Instituto de Salud Carlos III","award":["PEP:HB-16-JF-VG-C"],"award-info":[{"award-number":["PEP:HB-16-JF-VG-C"]}]},{"name":"Fondo de Investigaci\u00f3n en Salud of the Instituto de Salud Carlos III","award":["REIPI RD16\/0016\/0010"],"award-info":[{"award-number":["REIPI RD16\/0016\/0010"]}]},{"name":"Ajut a la Recerca \u201cCl\u00ednic-La Pedrera\u201d 2016","award":["PI 14\/01898"],"award-info":[{"award-number":["PI 14\/01898"]}]},{"name":"Ajut a la Recerca \u201cCl\u00ednic-La Pedrera\u201d 2016","award":["PEP:HB-16-JF-VG-C"],"award-info":[{"award-number":["PEP:HB-16-JF-VG-C"]}]},{"name":"Ajut a la Recerca \u201cCl\u00ednic-La Pedrera\u201d 2016","award":["REIPI RD16\/0016\/0010"],"award-info":[{"award-number":["REIPI RD16\/0016\/0010"]}]},{"DOI":"10.13039\/501100004587","name":"Instituto de Salud Carlos III","doi-asserted-by":"publisher","award":["PI 14\/01898"],"award-info":[{"award-number":["PI 14\/01898"]}],"id":[{"id":"10.13039\/501100004587","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004587","name":"Instituto de Salud Carlos III","doi-asserted-by":"publisher","award":["PEP:HB-16-JF-VG-C"],"award-info":[{"award-number":["PEP:HB-16-JF-VG-C"]}],"id":[{"id":"10.13039\/501100004587","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004587","name":"Instituto de Salud Carlos III","doi-asserted-by":"publisher","award":["REIPI RD16\/0016\/0010"],"award-info":[{"award-number":["REIPI RD16\/0016\/0010"]}],"id":[{"id":"10.13039\/501100004587","id-type":"DOI","asserted-by":"publisher"}]},{"name":"European Development Regional Fund \u201cA way to achieve Europe\u201d","award":["PI 14\/01898"],"award-info":[{"award-number":["PI 14\/01898"]}]},{"name":"European Development Regional Fund \u201cA way to achieve Europe\u201d","award":["PEP:HB-16-JF-VG-C"],"award-info":[{"award-number":["PEP:HB-16-JF-VG-C"]}]},{"name":"European Development Regional Fund \u201cA way to achieve Europe\u201d","award":["REIPI RD16\/0016\/0010"],"award-info":[{"award-number":["REIPI RD16\/0016\/0010"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>The aim of this study was to evaluate the diagnostic performance of plasma Lipocalin-2 (LCN2) concentration in adult patients with community-acquired pneumonia (CAP) to determine its etiology, severity and prognosis. A prospective observational study involving adults with CAP from November 2015 to May 2017 was conducted. Plasma LCN2 concentration was measured upon admission by a modified enzyme immunoassay coupled with chemiluminescence (Architect, Abbott Laboratories). The diagnostic performance of LCN2, C-reactive protein (CRP) and white blood cell to predict bacterial CAP was assessed. A total of 130 patients with CAP were included: 71 (54.6%) bacterial CAP, 42 (32.3%) unknown origin CAP and 17 (13.1%) viral CAP. LCN2 was higher in bacterial CAP than in non-bacterial CAP (122.0 vs. 89.7 ng\/mL, respectively) (p = 0.03) with a limited ability to distinguish bacterial and non-bacterial CAP (AUROC: 0.62 [95% CI 0.52\u20130.72]). The LCN2 cutoff \u2265 204 ng\/mL predicted the presence of pneumococcal bacteremia with an AUROC of 0.74 (sensitivity 70%, specificity 79.1%). Regarding severity, as defined by CURB-65 and PSI scores, there was a significant linear trend in the mean concentration of LCN2, exhibiting a shift from the low-risk to the intermediate-risk and high-risk group (p &lt; 0.001 and 0.001, respectively). LCN2 concentration was associated with severity in adult patients with CAP. However, its utility as a biomarker to discriminate viral and bacterial etiology in CAP is limited.<\/jats:p>","DOI":"10.3390\/microorganisms11051160","type":"journal-article","created":{"date-parts":[[2023,4,28]],"date-time":"2023-04-28T09:54:53Z","timestamp":1682675693000},"page":"1160","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Evaluation of Plasma Lipocalin-2 as a Predictor of Etiology and Severity in Adult Patients with Community-Acquired Pneumonia"],"prefix":"10.3390","volume":"11","author":[{"given":"Luc\u00eda","family":"Boix-Palop","sequence":"first","affiliation":[{"name":"Infectious Diseases Department, Hospital Universitari M\u00fatua de Terrassa, 08221 Terrassa, Spain"},{"name":"School of Medicine, University of Barcelona, 08908 Barcelona, Spain"},{"name":"School of Medicine, Universitat Internacional de Catalunya, 08195 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea","family":"Vergara","sequence":"additional","affiliation":[{"name":"School of Medicine, University of Barcelona, 08908 Barcelona, Spain"},{"name":"Biomedical Diagnostic Center (CDB), Department of Clinical Microbiology, Hospital Clinic of Barcelona, 08036 Barcelona, Spain"},{"name":"Instituto de Salud Global (ISGlobal), 08036 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emma","family":"Padilla","sequence":"additional","affiliation":[{"name":"Department of Clinical Microbiology, Catlab, 08232 Viladecavalls, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Diego","family":"Mart\u00ednez","sequence":"additional","affiliation":[{"name":"Biomedical Diagnostic Center (CDB), Department of Clinical Microbiology, Hospital Clinic of Barcelona, 08036 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ana","family":"Blanco","sequence":"additional","affiliation":[{"name":"Department of Clinical Microbiology, Catlab, 08232 Viladecavalls, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Josefa","family":"P\u00e9rez","sequence":"additional","affiliation":[{"name":"Department of Clinical Microbiology, Catlab, 08232 Viladecavalls, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Esther","family":"Calbo","sequence":"additional","affiliation":[{"name":"Infectious Diseases Department, Hospital Universitari M\u00fatua de Terrassa, 08221 Terrassa, Spain"},{"name":"School of Medicine, Universitat Internacional de Catalunya, 08195 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8025-3926","authenticated-orcid":false,"given":"Jordi","family":"Vila","sequence":"additional","affiliation":[{"name":"School of Medicine, University of Barcelona, 08908 Barcelona, Spain"},{"name":"Biomedical Diagnostic Center (CDB), Department of Clinical Microbiology, Hospital Clinic of Barcelona, 08036 Barcelona, Spain"},{"name":"Instituto de Salud Global (ISGlobal), 08036 Barcelona, Spain"},{"name":"CIBER de Enfermedades Infecciosas (CIBERINFEC), ISCIII, 28006 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Climent","family":"Casals-Pascual","sequence":"additional","affiliation":[{"name":"School of Medicine, University of Barcelona, 08908 Barcelona, Spain"},{"name":"Biomedical Diagnostic Center (CDB), Department of Clinical Microbiology, Hospital Clinic of Barcelona, 08036 Barcelona, Spain"},{"name":"Instituto de Salud Global (ISGlobal), 08036 Barcelona, Spain"},{"name":"CIBER de Enfermedades Infecciosas (CIBERINFEC), ISCIII, 28006 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2095","DOI":"10.1016\/S0140-6736(12)61728-0","article-title":"Global and regional mortality from 235 causes of death for 20 age groups in 1990 and 2010: A systematic analysis for the Global Burden of Disease Study 2010","volume":"380","author":"Lozano","year":"2012","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"876","DOI":"10.1055\/s-0036-1592125","article-title":"The Modern Diagnostic Approach to Community-Acquired Pneumonia in Adults","volume":"37","author":"Chalmers","year":"2016","journal-title":"Semin. 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