{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T09:09:37Z","timestamp":1780304977378,"version":"3.54.0"},"reference-count":33,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,5,31]],"date-time":"2026-05-31T00:00:00Z","timestamp":1780185600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Clinics and Practice"],"abstract":"<jats:p>Background: Long COVID in children is increasingly recognized, yet its clinical predictors and objective biological correlates remain insufficiently characterized. Objectives: The objective was to compare clinical, demographic, and laboratory characteristics between children with and without long COVID and to identify associated variables. Methods: We conducted a retrospective observational case\u2013control study at the \u201cDr. Victor Gomoiu\u201d Children\u2019s Clinical Hospital, including pediatric patients with confirmed SARS-CoV-2 infection. Cases were defined as children with symptoms persisting \u226512 weeks after acute infection, while controls had no persistent symptoms at \u226512 weeks. Results: Eighty-nine children with long COVID and 88 matched controls were included. Children with long COVID were significantly older (1.79 \u00b1 0.90 vs. 1.14 \u00b1 0.80 years, p &lt; 0.001) and more frequently from urban areas (86.5% vs. 69.3%, p = 0.0099). Lymphocyte, monocyte, and basophil counts were significantly lower in the Long COVID group, while D-dimer, ferritin, serum iron, urea, and creatinine levels were significantly higher. A multivariate predictive model demonstrated excellent discrimination (AUC = 0.94), with optimal sensitivity (84.3%) and specificity (89.8%) at a probability threshold of 0.48. Conclusions: Long COVID in children was associated with identifiable clinicobiological features. An exploratory composite model showed good discrimination but requires external validation.<\/jats:p>","DOI":"10.3390\/clinpract16060105","type":"journal-article","created":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T08:09:16Z","timestamp":1780301356000},"page":"105","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Factors Associated with Long COVID in the Pediatric Population: A Retrospective Case\u2013Control Study"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-9107-6637","authenticated-orcid":false,"given":"Ioana Maria Otilia","family":"Lic\u0103","sequence":"first","affiliation":[{"name":"Pediatric Department, University of Medicine and Pharmacy \u201cCarol Davila\u201d, 020021 Bucharest, Romania"},{"name":"\u201cDr. Victor Gomoiu\u201d Children\u2019s Clinical Hospital, 022102 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4133-5726","authenticated-orcid":false,"given":"Iulia Florentina","family":"\u021aincu","sequence":"additional","affiliation":[{"name":"Pediatric Department, University of Medicine and Pharmacy \u201cCarol Davila\u201d, 020021 Bucharest, Romania"},{"name":"\u201cDr. Victor Gomoiu\u201d Children\u2019s Clinical Hospital, 022102 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anca Cristina","family":"Dr\u0103g\u0103nescu","sequence":"additional","affiliation":[{"name":"Pediatric Department, University of Medicine and Pharmacy \u201cCarol Davila\u201d, 020021 Bucharest, Romania"},{"name":"National Institute of Infectious Diseases \u201cProf. Dr. Matei Bal\u0219\u201d, 021105 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8849-6834","authenticated-orcid":false,"given":"Doina Anca","family":"Ple\u0219ca","sequence":"additional","affiliation":[{"name":"Pediatric Department, University of Medicine and Pharmacy \u201cCarol Davila\u201d, 020021 Bucharest, Romania"},{"name":"National Institute of Infectious Diseases \u201cProf. Dr. Matei Bal\u0219\u201d, 021105 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"314","DOI":"10.1016\/S2213-2600(23)00081-4","article-title":"Clinical case definition of post-COVID-19 condition in children: A good start, but improvements are needed","volume":"11","author":"Burki","year":"2023","journal-title":"Lancet Respir. 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