{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T12:17:30Z","timestamp":1787833050861,"version":"build-2784847793"},"reference-count":50,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T00:00:00Z","timestamp":1787788800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"University of Oradea"},{"id":[{"id":"https:\/\/ror.org\/00wzhv093","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Children"],"abstract":"<jats:p>Background\/Objectives: Distinguishing perforated from non-perforated appendicitis preoperatively is difficult, and routine scores diagnose appendicitis rather than grade severity. We examined whether two inflammatory markers and one sonographic sign, combined in a model, discriminate between perforated and non-perforated appendicitis, and how this compares with a bedside score. Methods: Retrospective single-center cohort of 142 children aged 3\u201317 years undergoing initially attempted laparoscopic appendectomy (October 2022\u2013December 2023). Log-transformed neutrophil-to-lymphocyte ratio (NLR) and C-reactive protein (CRP) were prespecified; sonographic free peritoneal fluid was selected from four signs using the outcome, and reported in-sample performance is an upper bound. Predictors were fitted by Firth penalized logistic regression with bootstrap validation. Results: Perforation occurred in 27 patients (19.0%). All three were independent predictors (odds ratios: CRP 2.583, NLR 3.045, free peritoneal fluid 3.638). The area under the curve was 0.900 (0.890 optimism-corrected). At the Youden-optimal threshold, sensitivity was 96.3% and negative predictive value 98.9%. The Pediatric Appendicitis Score reached 0.855 (difference not significant, p = 0.375); at matched sensitivity its specificity was 38.9% versus 74.8%. Conclusions: The model\u2019s potential value lies in excluding perforation rather than establishing it, and applies after the decision to operate has been taken, informing antibiotic selection, operative urgency and family counselling rather than the indication for surgery. Overall discrimination did not differ significantly from the Pediatric Appendicitis Score, the advantage lying in the operating point rather than in the area under the curve. These findings are hypothesis-generating and require external validation.<\/jats:p>","DOI":"10.3390\/children13091152","type":"journal-article","created":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T10:58:21Z","timestamp":1787828301000},"page":"1152","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Preoperative Inflammatory Markers and Sonographic Free Peritoneal Fluid in Relation to Histopathologically Confirmed Appendiceal Perforation in Children: A Retrospective Cohort Study"],"prefix":"10.3390","volume":"13","author":[{"given":"Paul","family":"Tchouala Tchakoute","sequence":"first","affiliation":[{"name":"Doctoral School of Biomedical Sciences, University of Oradea, 410073 Oradea, Romania"},{"name":"Department of Pediatric Surgery and Orthopedics, Bihor County Emergency Clinical Hospital, 410469 Oradea, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-6966-4920","authenticated-orcid":false,"given":"R\u0103zvan","family":"Ro\u0219ca","sequence":"additional","affiliation":[{"name":"Department for the Prevention and Control of Healthcare-Associated Infections (CPIAAM), Clinical Hospital of Infectious Diseases and Pulmonology \u201cDr. Victor Babe\u0219\u201d Timi\u0219oara, Gheorghe Adam Street No. 13, 300310 Timi\u0219oara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2463-8100","authenticated-orcid":false,"given":"Alin","family":"Iuhas","sequence":"additional","affiliation":[{"name":"Department of Medical Disciplines, Faculty of Medicine and Pharmacy, University of Oradea, 410087 Oradea, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3097-707X","authenticated-orcid":false,"given":"Vlad-Ionu\u021b","family":"Nechita","sequence":"additional","affiliation":[{"name":"Department of Fundamental Sciences, Discipline of Medical Informatics, Research Methodology and Data Analysis, Faculty of Nursing and Health Sciences (FAMSS), \u201cIuliu Ha\u021bieganu\u201d University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristian Phillip","family":"Marin\u0103u","sequence":"additional","affiliation":[{"name":"Department of Medical Disciplines, Faculty of Medicine and Pharmacy, University of Oradea, 410087 Oradea, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-2638-2021","authenticated-orcid":false,"given":"Mihaela \u0218tefania","family":"Buzdugan","sequence":"additional","affiliation":[{"name":"Doctoral School of Biomedical Sciences, University of Oradea, 410073 Oradea, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2638-9056","authenticated-orcid":false,"given":"Ion Cosmin","family":"Puia","sequence":"additional","affiliation":[{"name":"Doctoral School of Biomedical Sciences, University of Oradea, 410073 Oradea, Romania"},{"name":"Department of Surgery, \u201cOctavian Fodor\u201d Regional Institute of Gastroenterology and Hepatology, 400162 Cluj-Napoca, Romania"},{"name":"Department of Surgery, \u201cIuliu Ha\u021bieganu\u201d University of Medicine and Pharmacy, 400162 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,27]]},"reference":[{"key":"ref_1","unstructured":"Waseem, M., and Wang, C.F. 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