{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T16:57:41Z","timestamp":1791910661715,"version":"4.3.4"},"reference-count":18,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,2,13]],"date-time":"2026-02-13T00:00:00Z","timestamp":1770940800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Post-infectious bronchiolitis obliterans (PIBO) is a rare but severe chronic lung disease of childhood, characterized by irreversible small-airway obstruction following severe lower respiratory tract infections early in life. The disease course is often progressive and associated with long-term respiratory morbidity, while effective disease-modifying therapies remain limited. We report the case of a young child who developed severe PIBO following adenovirus pneumonia complicated by prolonged respiratory failure and multisystem involvement. Diagnosis was based on persistent respiratory symptoms, characteristic radiologic findings, and poor response to conventional anti-inflammatory treatment. Given the severity of the clinical course and steroid-refractory disease, an individualized immunomodulatory strategy, including hydroxychloroquine, was initiated within a multidisciplinary framework. During follow-up, the patient showed progressive clinical improvement, with gradual weaning from continuous oxygen supplementation, fewer respiratory exacerbations, simplification of systemic therapies, and radiologic findings consistent with partial improvement. Although causal conclusions regarding treatment efficacy cannot be drawn from a single case, the overall disease trajectory appeared more favorable than typically reported in PIBO cohorts. This case supports the emerging view of PIBO as an immune-mediated airway fibrotic disorder and underscores the importance of integrating detailed clinical phenotyping with evolving molecular insights to inform future precision medicine in pediatric post-infectious airway disease.<\/jats:p>","DOI":"10.3390\/ijms27041804","type":"journal-article","created":{"date-parts":[[2026,2,13]],"date-time":"2026-02-13T12:06:59Z","timestamp":1770984419000},"page":"1804","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Post-Infectious Bronchiolitis Obliterans as a Model of Immune-Mediated Airway Fibrosis: A Pediatric Case Report"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-8589-956X","authenticated-orcid":false,"given":"Rosamaria","family":"Terracciano","sequence":"first","affiliation":[{"name":"Department of Translational Medicine, Section of Pediatrics, University of Naples \u201cFederico II\u201d, 80129 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-5024-2999","authenticated-orcid":false,"given":"Martina","family":"Mazzoni","sequence":"additional","affiliation":[{"name":"Department of Medicine, Surgery and Dentistry \u201cScuola Medica Salernitana\u201d, Pediatrics Section, University of Salerno, 84081 Baronissi, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1807-3884","authenticated-orcid":false,"given":"Alessandro","family":"Rossi","sequence":"additional","affiliation":[{"name":"Unit of Pediatric Pneumology and UTSIR, Santobono-Pausilipon Children\u2019s Hospital, 80129 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fabio","family":"Antonelli","sequence":"additional","affiliation":[{"name":"Unit of Pediatric Pneumology and UTSIR, Santobono-Pausilipon Children\u2019s Hospital, 80129 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pierluigi","family":"Vuilleumier","sequence":"additional","affiliation":[{"name":"Unit of Pediatric Pneumology and UTSIR, Santobono-Pausilipon Children\u2019s Hospital, 80129 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniela","family":"Melis","sequence":"additional","affiliation":[{"name":"Department of Medicine, Surgery and Dentistry \u201cScuola Medica Salernitana\u201d, Pediatrics Section, University of Salerno, 84081 Baronissi, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4685-7205","authenticated-orcid":false,"given":"Annalisa","family":"Allegorico","sequence":"additional","affiliation":[{"name":"Unit of Pediatric Pneumology and UTSIR, Santobono-Pausilipon Children\u2019s Hospital, 80129 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Wan, L., and Wang, Z. (2025). Postinfectious Bronchiolitis Obliterans in Children. Can. Respir. J., 2025.","DOI":"10.1155\/carj\/7790381"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"212","DOI":"10.1002\/ppul.24221","article-title":"Post-infectious bronchiolitis obliterans","volume":"54","author":"Colom","year":"2018","journal-title":"Pediatr. Pulmonol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"220188","DOI":"10.1183\/16000617.0188-2022","article-title":"Diagnostic workup of childhood interstitial lung disease","volume":"32","author":"Nathan","year":"2023","journal-title":"Eur. Respir. Rev."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1820","DOI":"10.1056\/NEJMra1204664","article-title":"Obliterative Bronchiolitis","volume":"370","author":"Barker","year":"2014","journal-title":"N. Engl. J. Med."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"290","DOI":"10.1016\/j.pharmthera.2013.07.008","article-title":"Bronchial epithelium as a target for innovative treatments in asthma","volume":"140","author":"Gras","year":"2013","journal-title":"Pharmacol. Ther."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"325","DOI":"10.1007\/s00430-019-00645-2","article-title":"Human adenovirus binding to host cell receptors: A structural view","volume":"209","author":"Stasiak","year":"2019","journal-title":"Med. Microbiol. Immunol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"507","DOI":"10.1080\/01902140701756604","article-title":"Interleukin-17 in pulmonary host defense","volume":"33","author":"Aujla","year":"2007","journal-title":"Exp. Lung Res."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Strunz, M., Simon, L.M., Ansari, M., Kathiriya, J.J., Angelidis, I., Mayr, C.H., Tsidiridis, G., Lange, M., Mattner, L.F., and Yee, M. (2020). Alveolar regeneration through a Krt8+ transitional stem cell state that persists in human lung fibrosis. Nat. Commun., 11.","DOI":"10.1038\/s41467-020-17358-3"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"934","DOI":"10.1038\/s41556-020-0542-8","article-title":"Persistence of a regeneration-associated, transitional alveolar epithelial cell state in pulmonary fibrosis","volume":"22","author":"Kobayashi","year":"2020","journal-title":"Nat. Cell Biol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1038\/mi.2008.85","article-title":"Pulmonary fibrosis: Pathogenesis, etiology and regulation","volume":"2","author":"Wilson","year":"2009","journal-title":"Mucosal Immunol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"eaba1972","DOI":"10.1126\/sciadv.aba1972","article-title":"Single-cell RNA sequencing reveals profibrotic roles of distinct epithelial and mesenchymal lineages in pulmonary fibrosis","volume":"6","author":"Habermann","year":"2020","journal-title":"Sci. Adv."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"eaba1983","DOI":"10.1126\/sciadv.aba1983","article-title":"Single-cell RNA-seq reveals ectopic and aberrant lung-resident cell populations in idiopathic pulmonary fibrosis","volume":"6","author":"Adams","year":"2020","journal-title":"Sci. Adv."},{"key":"ref_13","first-page":"58","article-title":"Post viral bronchiolitis obliterans in children: A rare and potentially devastating disease","volume":"52","author":"Mazenq","year":"2024","journal-title":"Paediatr. Respir. Rev."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Yuan, J., Wei, M., Chen, M., Wang, R., Diao, J., Tian, M., Zhao, D., and Chen, M. (2024). Risk factors for the development of bronchiolitis obliterans in children after suffering from adenovirus pneumonia. Front. Pediatr., 11.","DOI":"10.3389\/fped.2023.1335543"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"4101","DOI":"10.2147\/IDR.S372940","article-title":"Clinical Analysis and Risk Factors of Bronchiolitis Obliterans After Mycoplasma Pneumoniae Pneumonia","volume":"15","author":"Zheng","year":"2022","journal-title":"Infect. Drug Resist."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Zou, M., Zhai, Y., Mei, X., and Wei, X. (2023). Lactate dehydrogenase and the severity of adenoviral pneumonia in children: A meta-analysis. Front. Pediatr., 10.","DOI":"10.3389\/fped.2022.1059728"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"2387","DOI":"10.1084\/jem.20162152","article-title":"Monocyte-derived alveolar macrophages drive lung fibrosis and persist in the lung over the life span","volume":"214","author":"Misharin","year":"2017","journal-title":"J. Exp. Med."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"169","DOI":"10.1136\/thoraxjnl-2014-205328","article-title":"Pulmonary function of a paediatric cohort of patients with postinfectious bronchiolitis obliterans. A long term follow-up","volume":"70","author":"Colom","year":"2014","journal-title":"Thorax"}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/27\/4\/1804\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,2,13]],"date-time":"2026-02-13T12:07:28Z","timestamp":1770984448000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/27\/4\/1804"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,2,13]]},"references-count":18,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2026,2]]}},"alternative-id":["ijms27041804"],"URL":"https:\/\/doi.org\/10.3390\/ijms27041804","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,2,13]]}}}