Geldof J, Iqbal N, LeBlanc JF, Anandabaskaran S, Sawyer R, Buskens C, Bemelman W, Gecse K, Lundby L, Lightner AL, Danese S, Spinelli A, Carvello M, Faiz O, Warusavitarne J, Lung P, De Looze D, D'Hoore A, Vermeire S, Hart A, and Tozer P
Perianal fistulising Crohn's disease is an aggressive disease phenotype that can have a substantial detrimental impact on patients' quality of life. Current biological understanding of perianal fistulising Crohn's disease remains inadequate and previous classification systems have not provided clear guidance on therapy in clinical practice nor on defining patient cohorts within clinical trials. We propose a new classification system for perianal fistulising Crohn's disease that was developed through a modified nominal group technique expert consensus process. The classification identifies four groups of patients. Key elements include stratification according to disease severity as well as disease outcome; synchronisation of patient and clinician goals in decision making, with a proactive, combined medical and surgical approach, on a treat to patient goal basis; and identification of indications for curative fistula treatment, diverting ostomy, and proctectomy. The new classification retains an element of flexibility, in which patients can cycle through different classes over time. Furthermore, with each specific class comes a paired treatment strategy suggestion and description of clinical trial suitability. The proposed classification system is the first of its kind and is an important step towards tailored standardisation of clinical practice and research in patients with perianal fistulising Crohn's disease., Competing Interests: Declaration of interests JG has served as an advisory board member or speaker for Arena and Janssen. NI is funded by a Royal College of Surgeons research fellowship, sponsored by the Ileostomy & Internal Pouch Association. JFL has served as a speaker for Janssen. SA is supported through an Australian Government Research Training Program Scholarship. CJB has an unrestricted grant from Boehringer Ingelheim and Roche, and has received speaker fees from Takeda, Tillotts, and Galapagos. KBG has received grants from Pfizer Inc and Celltrion; consultancy fees from AbbVie, Arena Pharmaceuticals, Galapagos, Gilead, ImmunicTherapeutics, Janssen Pharmaceuticals, Novartis, Pfizer Inc, Samsung Bioepis, and Takeda, and speaker's honoraria from Celltrion, Ferring, Janssen Pharmaceuticals, Novartis, Pfizer Inc, Samsung Bioepis, Takeda, and Tillotts. ALL has served as a consultant for Takeda. SD reports consultancy fees from AbbVie, Alimentiv, Allergan, Amgen, AstraZeneca, Athos Therapeutics, Biogen, Boehringer Ingelheim, Celgene, Celltrion, Eli Lilly, Enthera, Ferring Pharmaceuticals Inc., Gilead, Hospira, Inotrem, Janssen, Johnson & Johnson, MSD, Mundipharma, Mylan, Pfizer, Roche, Sandoz, Sublimity Therapeutics, Takeda, TiGenix, UCB Inc, and Vifor. AS has served as speaker for Takeda, Johnson and Johnson, and Pfizer. MC has served as speaker for Pfizer. AD'H has served as speaker for Johnson & Johnson and Takeda. SV has received grants from AbbVie, J&J, Pfizer, and Takeda; and has received consulting and/or speaking fees from AbbVie, Arena Pharmaceuticals, Avaxia, Boehringer Ingelheim, Celgene, Dr Falk Pharma, Ferring, Galapagos, Genentech-Roche, Gilead, Hospira, Janssen, Mundipharma, MSD, Pfizer, Prodigest, Progenity, Prometheus, Robarts Clinical Trials, Second Genome, Shire, Takeda, Theravance, and Tillots Pharma AG. AH has served as consultant, advisory board member or speaker for AbbVie, Arena, Atlantic, Bristol-Myers Squibb, Celgene, Celltrion, Falk, Ferring, Janssen, MSD, Napp Pharmaceuticals, Pfizer, Pharmacosmos, Shire, and Takeda, and serves on the global steering committee for Genentech. PT has acted as speaker and/or served on advisory boards for Takeda and Ferring. All other authors declared no competing interests., (Copyright © 2022 Elsevier Ltd. All rights reserved.)