{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,19]],"date-time":"2026-09-19T00:43:54Z","timestamp":1789778634665,"version":"4.0.1"},"reference-count":96,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,1,22]],"date-time":"2026-01-22T00:00:00Z","timestamp":1769040000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Life"],"abstract":"<jats:p>Perianal fistulizing Crohn\u2019s disease (pfCD) represents one of the most challenging manifestations of CD, often associated with severe phenotypes, refractory luminal inflammation, and a substantial reduction in quality of life. Its pathogenesis is multifactorial and incompletely understood, involving genetic susceptibility, epithelial and stromal dysfunction, and microbiome-related mechanisms. Diagnosis and monitoring rely on advanced imaging, while management requires coordinated medical\u2013surgical strategies. Significant unmet needs persist regarding standardized treatment targets, optimal imaging follow-up, and personalized therapeutic pathways. In this review, we aim to summarise and provide a comprehensive overview of the most recent evidence across pathogenesis, diagnosis, classification systems, and therapeutic approaches in pfCD. We highlight key advances in understanding epithelial\u2013mesenchymal transition, immune\u2013microbiome interactions, and genetic determinants of disease behaviour. Improvements in diagnostic modalities\u2014including MRI-based scores, ultrasound technologies, volumetric assessment, and AI-enhanced imaging\u2014are discussed alongside modern classification systems such as TOPClass. Evidence guiding medical therapy, seton management, and surgical decision-making is reviewed, emphasising integrated, goal-oriented care. Despite substantial progress, pfCD remains a difficult-to-treat condition with persistent gaps in early diagnosis, objective monitoring, and individualized management. Emerging imaging technologies, standardized treatment targets, and structured classification frameworks offer promising strategies to overcome current limitations and improve long-term outcomes.<\/jats:p>","DOI":"10.3390\/life16010182","type":"journal-article","created":{"date-parts":[[2026,1,23]],"date-time":"2026-01-23T10:41:34Z","timestamp":1769164894000},"page":"182","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Perianal Crohn\u2019s Disease in Inflammatory Bowel Disease: Diagnosis, Assessment and Treatment"],"prefix":"10.3390","volume":"16","author":[{"given":"Ilaria","family":"Faggiani","sequence":"first","affiliation":[{"name":"Department of Gastroenterology and Endoscopy, IRCCS San Raffaele Hospital and Vita-Salute San Raffaele University, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-7556-1111","authenticated-orcid":false,"given":"Isabel Lagos","family":"Villaseca","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, Clinica Las Condes, Santiago 7550000, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8591-6995","authenticated-orcid":false,"given":"Ferdinando","family":"D\u2019Amico","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Endoscopy, IRCCS San Raffaele Hospital and Vita-Salute San Raffaele University, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Federica","family":"Furfaro","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Endoscopy, IRCCS San Raffaele Hospital and Vita-Salute San Raffaele University, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandra","family":"Zilli","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Endoscopy, IRCCS San Raffaele Hospital and Vita-Salute San Raffaele University, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3214-8192","authenticated-orcid":false,"given":"Sara","family":"Massironi","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Endoscopy, IRCCS San Raffaele Hospital and Vita-Salute San Raffaele University, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tommaso Lorenzo","family":"Parigi","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Endoscopy, IRCCS San Raffaele Hospital and Vita-Salute San Raffaele University, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Virginia","family":"Solitano","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Endoscopy, IRCCS San Raffaele Hospital and Vita-Salute San Raffaele University, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-5400-2765","authenticated-orcid":false,"given":"Clelia","family":"Cicerone","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Endoscopy, IRCCS San Raffaele Hospital and Vita-Salute San Raffaele University, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laurent","family":"Peyrin-Biroulet","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, INFINY Institute, INSERM NGERE, CHRU Nancy, F-54500 Vandoeuvre-l\u00e8s-Nancy, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7341-1351","authenticated-orcid":false,"given":"Silvio","family":"Danese","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Endoscopy, IRCCS San Raffaele Hospital and Vita-Salute San Raffaele University, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mariangela","family":"Allocca","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Endoscopy, IRCCS San Raffaele Hospital and Vita-Salute San Raffaele University, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"101767","DOI":"10.4240\/wjgs.v17.i7.101767","article-title":"Epidemiology, Treatment Patterns, and Associated Risk Factors in Perianal Fistulizing Crohn\u2019s Disease: A Systematic Literature Review","volume":"17","author":"McKay","year":"2025","journal-title":"World J. 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