{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,9]],"date-time":"2026-10-09T04:28:03Z","timestamp":1791520083458,"version":"4.3.4"},"reference-count":102,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,1,6]],"date-time":"2023-01-06T00:00:00Z","timestamp":1672963200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004543","name":"China Scholarship Council","doi-asserted-by":"publisher","award":["201806270259"],"award-info":[{"award-number":["201806270259"]}],"id":[{"id":"10.13039\/501100004543","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Perianal fistulas are defined as pathological connections between the anorectal canal and the perianal skin. Most perianal fistulas are cryptoglandular fistulas, which are thought to originate from infected anal glands. The remainder of the fistulas mainly arises as complications of Crohn\u2019s disease (CD), trauma, or as a result of malignancies. Fistulas in CD are considered as a consequence of a chronic and transmural inflammatory process in the distal bowel and can, in some cases, even precede the diagnosis of CD. Although both cryptoglandular and CD-associated fistulas might look similar macroscopically, they differ considerably in their complexity, treatment options, and healing rate. Therefore, it is of crucial importance to differentiate between these two types of fistulas. In this review, the differences between CD-associated and cryptoglandular perianal fistulas in epidemiology, pathogenesis, and clinical management are discussed. Finally, a flow chart is provided for physicians to guide them when dealing with patients displaying their first episode of perianal fistulas.<\/jats:p>","DOI":"10.3390\/jcm12020466","type":"journal-article","created":{"date-parts":[[2023,1,6]],"date-time":"2023-01-06T03:31:28Z","timestamp":1672975888000},"page":"466","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":44,"title":["Crohn\u2019s Disease-Associated and Cryptoglandular Fistulas: Differences and Similarities"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5914-1340","authenticated-orcid":false,"given":"Zhou","family":"Zhou","sequence":"first","affiliation":[{"name":"Department of Gastroenterology and Hepatology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7584-5644","authenticated-orcid":false,"given":"Laura F.","family":"Ouboter","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Hepatology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands"},{"name":"Department of Immunology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Koen C. M. J.","family":"Peeters","sequence":"additional","affiliation":[{"name":"Department of Surgery, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2274-9325","authenticated-orcid":false,"given":"Lukas J. A. C.","family":"Hawinkels","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Hepatology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fabian","family":"Holman","sequence":"additional","affiliation":[{"name":"Department of Surgery, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria F.","family":"Pascutti","sequence":"additional","affiliation":[{"name":"Department of Immunology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marieke C.","family":"Barnhoorn","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Hepatology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea E.","family":"van der Meulen-de Jong","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Hepatology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,6]]},"reference":[{"key":"ref_1","first-page":"175","article-title":"MR imaging evaluation of perianal fistulas: Spectrum of imaging features","volume":"32","author":"Rivas","year":"2012","journal-title":"Radiogr. 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