{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:38:37Z","timestamp":1787027917960,"version":"build-2736575974"},"reference-count":37,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2021,7,29]],"date-time":"2021-07-29T00:00:00Z","timestamp":1627516800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Objectives: COVID-19 may show no peculiar signs and symptoms that may differentiate it from other infective or non-infective etiologies; thus, early recognition and prompt management are crucial to improve survival. The aim of this study was to describe clinical, laboratory, and radiological characteristics and outcomes of hospitalized COVID-19 patients compared to those with other infective or non-infective etiologies. Methods: We performed a prospective study from March 2020 to February 2021. All patients hospitalized for suspected or confirmed COVID-19 were prospectively recruited. All patients were evaluated according to a predefined protocol for diagnosis of suspected SARS-CoV-2 infection. The primary endpoint was evaluation of clinical, laboratory, and radiological characteristics associated or not with COVID-19 etiology at time of hospitalization in an emergency department. Results: A total of 1036 patients were included in the study: 717 (69%) patients with confirmed COVID-19 and 319 (31%) without COVID-19, hospitalized for other causes. The main causes of hospitalization among non-COVID-19 patients were acute heart failure (44%) and bacterial pneumonia (45.8%). Overall, 30-day mortality was 9% among the COVID-19 group and 35% in the non-COVID-19 group. Multivariate analysis showed variables (fever &gt; 3 days, dry cough, acute dyspnea, lymphocytes &lt; 1000 \u00d7 103\/\u00b5L, and ferritin &gt; 250 ng\/mL) independently associated with COVID-19 etiology. A decision tree was elaborated to early detect COVID-19 patients in the emergency department. Finally, Kaplan\u2013Meier curves on 30-day survival in COVID-19 patients during the first wave (March\u2013May 2020, n = 289 patients) and the second wave (October\u2013February 2021, n = 428 patients) showed differences between the two study periods (p = 0.021). Conclusions: Patients with confirmed diagnosis of COVID-19 may show peculiar characteristics at time of hospitalization that could help physicians to distinguish from other infective or non-infective etiologies. Finally, a different 30-day mortality rate was observed during different periods of the pandemic.<\/jats:p>","DOI":"10.3390\/diagnostics11081368","type":"journal-article","created":{"date-parts":[[2021,7,29]],"date-time":"2021-07-29T10:47:46Z","timestamp":1627555666000},"page":"1368","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Clinical Characteristics and Outcome of Patients with Suspected COVID-19 in Emergency Department (RESILIENCY Study II)"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3846-4620","authenticated-orcid":false,"given":"Alessandro","family":"Russo","sequence":"first","affiliation":[{"name":"Department of Medical and Surgical Sciences, Infectious and Tropical Disease Unit, \u201cMagna Graecia\u201d University of Catanzaro, 88100 Catanzaro, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elio","family":"Gentilini Cacciola","sequence":"additional","affiliation":[{"name":"Policlinico \u201cUmberto I\u201d, Department of Public Health and Infectious Diseases, \u201cSapienza\u201d University of Rome, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2346-898X","authenticated-orcid":false,"given":"Cristian","family":"Borrazzo","sequence":"additional","affiliation":[{"name":"Policlinico \u201cUmberto I\u201d, Department of Public Health and Infectious Diseases, \u201cSapienza\u201d University of Rome, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Valeria","family":"Filippi","sequence":"additional","affiliation":[{"name":"Policlinico \u201cUmberto I\u201d, Department of Public Health and Infectious Diseases, \u201cSapienza\u201d University of Rome, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2895-6234","authenticated-orcid":false,"given":"Tommaso","family":"Bucci","sequence":"additional","affiliation":[{"name":"Department of General Surgery, Surgical Specialties and Organ Transplantation \u201cParide Stefanini\u201d, Sapienza University of Rome, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francesco","family":"Vullo","sequence":"additional","affiliation":[{"name":"Department of Radiological, Oncological and Pathological Sciences, \u201cSapienza\u201d University of Rome, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luigi","family":"Celani","sequence":"additional","affiliation":[{"name":"Policlinico \u201cUmberto I\u201d, Department of Public Health and Infectious Diseases, \u201cSapienza\u201d University of Rome, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Erica","family":"Binetti","sequence":"additional","affiliation":[{"name":"Policlinico \u201cUmberto I\u201d, Department of Public Health and Infectious Diseases, \u201cSapienza\u201d University of Rome, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luigi","family":"Battistini","sequence":"additional","affiliation":[{"name":"Policlinico \u201cUmberto I\u201d, Department of Public Health and Infectious Diseases, \u201cSapienza\u201d University of Rome, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5921-3180","authenticated-orcid":false,"given":"Giancarlo","family":"Ceccarelli","sequence":"additional","affiliation":[{"name":"Policlinico \u201cUmberto I\u201d, Department of Public Health and Infectious Diseases, \u201cSapienza\u201d University of Rome, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria","family":"Alessandroni","sequence":"additional","affiliation":[{"name":"Medical Emergency Unit, Sapienza University of Rome, Policlinico Umberto I, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gioacchino","family":"Galardo","sequence":"additional","affiliation":[{"name":"Medical Emergency Unit, Sapienza University of Rome, Policlinico Umberto I, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1286-467X","authenticated-orcid":false,"given":"Claudio Maria","family":"Mastroianni","sequence":"additional","affiliation":[{"name":"Policlinico \u201cUmberto I\u201d, Department of Public Health and Infectious Diseases, \u201cSapienza\u201d University of Rome, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3571-5677","authenticated-orcid":false,"given":"Gabriella","family":"d\u2019Ettorre","sequence":"additional","affiliation":[{"name":"Policlinico \u201cUmberto I\u201d, Department of Public Health and Infectious Diseases, \u201cSapienza\u201d University of Rome, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"497","DOI":"10.1016\/S0140-6736(20)30183-5","article-title":"Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China","volume":"395","author":"Huang","year":"2020","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"e13209","DOI":"10.1111\/eci.13209","article-title":"The novel Chinese coronavirus (2019-nCoV) infections: Challenges for fighting the storm","volume":"50","author":"Bassetti","year":"2020","journal-title":"Eur. J. Clin. Investig."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1054","DOI":"10.1016\/S0140-6736(20)30566-3","article-title":"Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: A retrospective cohort study","volume":"395","author":"Zhou","year":"2020","journal-title":"Lancet"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1537","DOI":"10.1016\/j.cmi.2020.07.049","article-title":"Clinical characteristics, management and in-hospital mortality of patients with coronavirus disease 2019 in Genoa, Italy","volume":"26","author":"Vena","year":"2020","journal-title":"Clin. Microbiol. Infect."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1545","DOI":"10.1016\/j.cmi.2020.08.003","article-title":"Development and validation of a prediction model for severe respiratory failure in hospitalized patients with SARS-CoV-2 infection: A multicentre cohort study (PREDI-CO study)","volume":"26","author":"Bartoletti","year":"2020","journal-title":"Clin. Microbiol. Infect."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"2000562","DOI":"10.1183\/13993003.00562-2020","article-title":"Clinical characteristics and outcomes of hospitalised patients with COVID-19 treated in Hubei (epicenter) and outside Hubei (non-epicenter): A Nationwide Analysis of China","volume":"55","author":"Liang","year":"2020","journal-title":"Eur. Respir. J."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1574","DOI":"10.1001\/jama.2020.5394","article-title":"Network, Baseline Characteristics and Outcomes of 1591 Patients Infected with SARS-CoV-2 Admitted to ICUs of the Lombardy Region, Italy","volume":"323","author":"Grasselli","year":"2020","journal-title":"JAMA"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"e1158","DOI":"10.1093\/cid\/ciaa1745","article-title":"Comparison Between Hospitalized Patients Affected or Not Affected by Coronavirus Disease 2019","volume":"72","author":"Russo","year":"2021","journal-title":"Clin. Infect. Dis."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"660","DOI":"10.1109\/21.97458","article-title":"A survey of decision tree classifier methodology","volume":"21","author":"Safavian","year":"1991","journal-title":"IEEE Trans. Syst. Man Cybern."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1016\/S0933-3657(01)00077-X","article-title":"Machine learning for medical diagnosis: History, state of the art and perspective","volume":"23","author":"Kononenko","year":"2001","journal-title":"Artif. Intell. Med."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"m3339","DOI":"10.1136\/bmj.m3339","article-title":"Risk stratification of patients admitted to hospital with covid-19 using the ISARIC WHO Clinical Characterisation Protocol: Development and validation of the 4C Mortality Score","volume":"370","author":"Knight","year":"2020","journal-title":"BMJ"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1307","DOI":"10.3389\/fphar.2020.01307","article-title":"The Potential Role of Heparin in Patients with COVID-19: Beyond the Anticoagulant Effect. A Review","volume":"11","author":"Gozzo","year":"2020","journal-title":"Front. Pharm."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1124","DOI":"10.3389\/fphar.2020.01124","article-title":"Preliminary Experience with Low Molecular Weight Heparin Strategy in COVID-19 Patients","volume":"11","author":"Paolisso","year":"2020","journal-title":"Front. Pharm."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1033","DOI":"10.1016\/S0140-6736(20)30628-0","article-title":"Hlh Across Speciality Collaboration, COVID-19: Consider cytokine storm syndromes and immunosuppression","volume":"395","author":"Mehta","year":"2020","journal-title":"Lancet"},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Iftimie, S., L\u00f3pez-Azcona, A.F., Vallverd\u00fa, I., Hern\u00e1ndez-Flix, S., de Febrer, G., Parra, S., Hern\u00e1ndez-Aguilera, A., Riu, F., Joven, J., and Andreychuk, N. (2021). First and second waves of coronavirus disease-19: A comparative study in hospitalized patients in Reus, Spain. PLoS ONE, 16.","DOI":"10.1101\/2020.12.10.20246959"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1919","DOI":"10.1038\/s41591-020-1112-0","article-title":"Magnitude, demographics and dynamics of the effect of the first wave of the COVID-19 pandemic on all-cause mortality in 21 industrialized countries","volume":"26","author":"Kontis","year":"2020","journal-title":"Nat. Med."},{"key":"ref_17","first-page":"ciaa1535","article-title":"StopCOVID cohort: An observational study of 3,480 patients admitted to the Sechenov University hospital network in Moscow city for suspected COVID-19 infection","volume":"73","author":"Munblit","year":"2020","journal-title":"Clin. Infect. Dis."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"m1985","DOI":"10.1136\/bmj.m1985","article-title":"Features of 20 133 UK patients in hospital with covid-19 using the ISARIC WHO Clinical Characterisation Protocol: Prospective observational cohort study","volume":"369","author":"Docherty","year":"2020","journal-title":"BMJ"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1708","DOI":"10.1056\/NEJMoa2002032","article-title":"Clinical Characteristics of Coronavirus Disease 2019 in China","volume":"382","author":"Guan","year":"2020","journal-title":"N. Engl. J. Med."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"448","DOI":"10.14740\/jocmr4240","article-title":"Use of Neutrophil-to-Lymphocyte and Platelet-to-Lymphocyte Ratios in COVID-19","volume":"12","author":"Chan","year":"2020","journal-title":"J. Clin. Med. Res."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"4863","DOI":"10.1038\/s41598-021-83831-8","article-title":"Ferritin is associated with the severity of lung involvement but not with worse prognosis in patients with COVID-19: Data from two Italian COVID-19 units","volume":"11","author":"Carubbi","year":"2021","journal-title":"Sci. Rep."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"4200","DOI":"10.1038\/s41598-021-83784-y","article-title":"Early risk assessment for COVID-19 patients from emergency department data using machine learning","volume":"11","author":"Heldt","year":"2021","journal-title":"Sci. Rep."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"4080","DOI":"10.1038\/s41467-020-17971-2","article-title":"Artificial intelligence for the detection of COVID-19 pneumonia on chest CT using multinational datasets","volume":"11","author":"Harmon","year":"2020","journal-title":"Nat. Commun."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1809","DOI":"10.1111\/all.14316","article-title":"Distinct characteristics of COVID-19 patients with initial rRT-PCR-positive and rRT-PCR-negative results for SARS-CoV-2","volume":"75","author":"Zhang","year":"2020","journal-title":"Allergy"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"427","DOI":"10.3389\/fmed.2020.00427","article-title":"Deep Learning-Based Decision-Tree Classifier for COVID-19 Diagnosis From Chest X-ray Imaging","volume":"7","author":"Yoo","year":"2020","journal-title":"Front. Med."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"475","DOI":"10.1016\/j.cca.2020.08.019","article-title":"Laboratory findings in COVID-19 diagnosis and prognosis","volume":"510","author":"Bashash","year":"2020","journal-title":"Clin. Chim. Acta."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"S\u00e1nchez-Monta\u00f1\u00e9s, M., Rodr\u00edguez-Belenguer, P., Serrano-L\u00f3pez, A.J., Soria-Olivas, E., and Alakhdar-Mohmara, Y. (2020). Machine Learning for Mortality Analysis in Patients with COVID-19. Int. J. Environ. Res. Public Health., 17.","DOI":"10.3390\/ijerph17228386"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1040.e7","DOI":"10.1016\/j.cmi.2021.04.005","article-title":"Not all COVID-19 pandemic waves are alike","volume":"27","author":"Domingo","year":"2021","journal-title":"Clin. Microbiol. Infect."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"200384","DOI":"10.1183\/16000617.0384-2020","article-title":"Current evidence for COVID-19 therapies: A systematic literature review","volume":"30","author":"Welte","year":"2021","journal-title":"Eur. Respir. Rev."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"673","DOI":"10.1177\/0885066621994057","article-title":"A Comparison of Methylprednisolone and Dexamethasone in Intensive Care Patients With COVID-19","volume":"36","author":"Ko","year":"2021","journal-title":"J. Intensive Care Med."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"ofaa563","DOI":"10.1093\/ofid\/ofaa563","article-title":"Role of Low-Molecular-Weight Heparin in Hospitalized Patients With Severe Acute Respiratory Syndrome Coronavirus 2 Pneumonia: A Prospective Observational Study","volume":"7","author":"Falcone","year":"2020","journal-title":"Open Forum Infect. Dis."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"872","DOI":"10.1182\/bloodadvances.2020003763","article-title":"American Society of Hematology 2021 guidelines on the use of anticoagulation for thromboprophylaxis in patients with COVID-19","volume":"5","author":"Cuker","year":"2021","journal-title":"Blood Adv."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Olender, S.A., Perez, K.K., Go, A.S., Balani, B., Price-Haywood, E.G., Shah, N.S., Wang, S., Walunas, T.L., Swaminathan, S., and Slim, J. (2020). Remdesivir for Severe COVID-19 versus a Cohort Receiving Standard of Care. Clin. Infect. Dis., ciaa1041.","DOI":"10.1093\/cid\/ciaa1041"},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"WHO Solidarity Trial Consortium, Pan, H., Peto, R., Henao-Restrepo, A.M., Preziosi, M.P., Sathiyamoorthy, V., Abdool Karim, Q., Alejandria, M.M., Hern\u00e1n-dez Garc\u00eda, C., and Kieny, M.P. (2021). Repurposed Antiviral Drugs for Covid-19\u2014Interim WHO Solidarity Trial Results. N. Engl. J. Med., 384, 497\u2013511.","DOI":"10.1056\/NEJMoa2023184"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"e440","DOI":"10.1097\/CCM.0000000000004363","article-title":"Surviving Sepsis Campaign: Guidelines on the Management of Critically Ill Adults with Coronavirus Disease 2019 (COVID-19)","volume":"48","author":"Alhazzani","year":"2020","journal-title":"Crit. Care Med."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"880","DOI":"10.1016\/j.cmi.2020.04.031","article-title":"Balancing evidence and frontline experience in the early phases of the COVID-19 pandemic: Current position of the Italian Society of Anti-Infective Therapy (SITA) and the Italian Society of Pulmonology (SIP)","volume":"26","author":"Bassetti","year":"2020","journal-title":"Clin. Microbiol. Infect."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1209","DOI":"10.1016\/S2213-2600(20)30366-0","article-title":"Prevalence of phenotypes of acute respiratory distress syndrome in critically ill patients with COVID-19: A prospective observational study","volume":"8","author":"Sinha","year":"2020","journal-title":"Lancet Respir. Med."}],"container-title":["Diagnostics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2075-4418\/11\/8\/1368\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:36:58Z","timestamp":1760164618000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2075-4418\/11\/8\/1368"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,7,29]]},"references-count":37,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2021,8]]}},"alternative-id":["diagnostics11081368"],"URL":"https:\/\/doi.org\/10.3390\/diagnostics11081368","relation":{},"ISSN":["2075-4418"],"issn-type":[{"value":"2075-4418","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,7,29]]}}}