{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T23:30:41Z","timestamp":1787009441455,"version":"build-2736575974"},"reference-count":44,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,5,9]],"date-time":"2025-05-09T00:00:00Z","timestamp":1746748800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Victor Babes University of Medicine and Pharmacy"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diseases"],"abstract":"<jats:p>Background and Objectives: Secondary bacterial pneumonia can substantially worsen the clinical trajectory of patients hospitalized for Coronavirus Disease 2019 (COVID-19). This study aimed to characterize bacterial superinfections in COVID-19, including pathogen profiles, resistance patterns, inflammatory responses, severity scores, and ICU admission risk. Methods: In a retrospective cohort design, we reviewed 141 patients admitted to a single tertiary-care hospital between February 2021 and December 2024. A total of 58 patients had laboratory-confirmed bacterial superinfection by sputum, bronchoalveolar lavage, or blood cultures (superinfection group), whereas 83 had COVID-19 without any documented bacterial pathogens (COVID-only group). We collected detailed microbiological data from sputum, bronchoalveolar lavage (BAL), and blood cultures. Antibiotic sensitivity testing was performed using standard breakpoints for multidrug resistance (MDR). Inflammatory markers (C-reactive protein, procalcitonin, neutrophil-to-lymphocyte ratio, and systemic immune-inflammation index) and the severity indices Acute Physiology and Chronic Health Evaluation (APACHE) II, Confusion, Urea, Respiratory rate, Blood pressure (CURB), and National Early Warning Score (NEWS) were measured at admission. Primary outcomes included intensive care unit (ICU) admission, mechanical ventilation, and mortality. Results: Patients in the superinfection group showed significantly elevated inflammatory markers and severity scores compared to the COVID-only group (mean APACHE II of 17.2 vs. 13.8; p &lt; 0.001). Pathogens most frequently isolated from sputum and BAL included Klebsiella pneumoniae (27.6%) and Pseudomonas aeruginosa (20.7%). Multidrug-resistant strains were documented in 32.8% of isolates. The superinfection group had higher ICU admissions (37.9% vs. 19.3%; p = 0.01) and more frequent mechanical ventilation (25.9% vs. 9.6%; p = 0.01). Mortality trended higher among superinfected patients (15.5% vs. 7.2%; p = 0.09). A total of 34% of the cohort had prior antibiotic use, which independently predicted MDR (aOR 2.6, p = 0.01). The presence of MDR pathogens such as Klebsiella pneumoniae (OR 2.8), Pseudomonas aeruginosa (OR 2.5), and Staphylococcus aureus (OR 2.1) significantly increases the risk of ICU admission. Conclusions: Bacterial superinfection exacerbates inflammation and worsens outcomes in COVID-19 patients, such as a higher risk of ICU admission.<\/jats:p>","DOI":"10.3390\/diseases13050145","type":"journal-article","created":{"date-parts":[[2025,5,9]],"date-time":"2025-05-09T04:13:44Z","timestamp":1746764024000},"page":"145","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Bacterial Superinfections After SARS-CoV-2 Pneumonia: Antimicrobial Resistance Patterns, Impact on Inflammatory Profiles, Severity Scores, and Clinical Outcomes"],"prefix":"10.3390","volume":"13","author":[{"given":"Petrinela","family":"Daliu","sequence":"first","affiliation":[{"name":"Doctoral School, \u201cVictor Babes\u201d University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Iulia","family":"Bogdan","sequence":"additional","affiliation":[{"name":"Methodological and Infectious Diseases Research Center, Department of Infectious Diseases, \u201cVictor Babes\u201d University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8236-2205","authenticated-orcid":false,"given":"Ovidiu","family":"Rosca","sequence":"additional","affiliation":[{"name":"Methodological and Infectious Diseases Research Center, Department of Infectious Diseases, \u201cVictor Babes\u201d University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandra Laura","family":"Aelenei","sequence":"additional","affiliation":[{"name":"Methodological and Infectious Diseases Research Center, Department of Infectious Diseases, \u201cVictor Babes\u201d University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ioan","family":"S\u00eerbu","sequence":"additional","affiliation":[{"name":"Department of Oral Implantology, Faculty of Dental Medicine, University of Medicine and Pharmacy \u201cCarol Davila\u201d, 050474 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mihai Calin","family":"Bica","sequence":"additional","affiliation":[{"name":"Doctoral School, \u201cVictor Babes\u201d University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9245-5883","authenticated-orcid":false,"given":"Monica","family":"Licker","sequence":"additional","affiliation":[{"name":"Multidisciplinary Research Center of Antimicrobial Resistance, Department of Microbiology, Faculty of Medicine, \u201cVictor Babes\u201d University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"},{"name":"Microbiology Laboratory, \u201cPius Brinzeu\u201d County Clinical Emergency Hospital, 300723 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elena","family":"Hogea","sequence":"additional","affiliation":[{"name":"Multidisciplinary Research Center of Antimicrobial Resistance, Department of Microbiology, Faculty of Medicine, \u201cVictor Babes\u201d University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9100-4530","authenticated-orcid":false,"given":"Delia","family":"Muntean","sequence":"additional","affiliation":[{"name":"Multidisciplinary Research Center of Antimicrobial Resistance, Department of Microbiology, Faculty of Medicine, \u201cVictor Babes\u201d University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"351","DOI":"10.1016\/j.bpa.2020.12.011","article-title":"COVID-19-associated acute respiratory distress syndrome (CARDS): Current knowledge on pathophysiology and ICU treatment\u2014A narrative review","volume":"35","author":"Pfortmueller","year":"2021","journal-title":"Best Pract. 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