P272 Reduced delay in diagnosis of Crohn’s disease in patients presenting with perianal disease: results of a retrospective cohort study at a non-academic, IBD-expert centre in the Netherlands

Munster, L.(1)*;de Groof, E.J.(1);van Dieren, S.(2);Mundt, M.W.(3);D’Haens, G.R.A.M.(4);Bemelman, W.A.(5);Buskens, C.J.(5);van der Bilt, J.D.W.(1);

(1)Flevoziekenhuis/Amsterdam UMC- location AMC, Department of Surgery, Almere/Amsterdam, The Netherlands;(2)Amsterdam UMC- location AMC, Department of Clinical Epidemiology, Amsterdam, The Netherlands;(3)Flevoziekenhuis, Department of Gastroenterology, Almere, The Netherlands;(4)Amsterdam UMC- location AMC, Department of Gastroenterology, Amsterdam, The Netherlands;(5)Amsterdam UMC- location AMC, Department of Surgery, Amsterdam, The Netherlands;


In up to 10% of patients with Crohn’s disease (CD), a perianal fistula (PAF) or perianal abscess (PAA) is the first presenting symptom. Delay in diagnosis in those patients is common and twice as long as in the general CD population. For the majority of patients (>70%) diagnosis takes >12 months. Delay is associated with more complex fistula formation impairing opportunities for clinical and radiological fistula closure, currently only successful in 65% and 30% respectively (combining anti-TNF and surgery). Moreover, delay in diagnosis is associated with worse outcomes and impaired quality of life (QoL). Since 2017, a low threshold for diagnostic work-up (ileocolonoscopy) for CD in patients presenting with perianal disease was introduced by a dedicated IBD surgeon in order to reduce delay in diagnosis of CD.


Patient records of all consecutive patients ≥16 years presenting with perianal disease (before diagnosis of CD) were retrospectively assessed. Differences in delay of diagnosis, defined as the time between first presentation with a PAA/PAF and confirmed diagnosis of CD, and differences in outcome measurements between the period 2007-2016 and 2017-2021 were determined in those eventually diagnosed with CD.


A total of 25 patients were included in this study (n=13 in 2007-2016 and n=12 in 2017-2021, 52% male) with median age at presentation of 27 years (IQR 21,5-38,5). In the period 2007-2016, a median delay of 33 months (IQR 23-64) in CD diagnosis was observed and less than 20% of patients were diagnosed within one year after the first perianal surgical procedure. In the period 2017-2021 the median time to diagnosis significantly decreased to only 3 months (IQR 0-5, p=,000) and the proportion of patients diagnosed within one year increased drastically up to 79% (p=,000). Due to the relatively limited number of patients, no significant differences in outcome measurements (e.g. (re)interventions before CD diagnosis, number of successful fistula closure rates (clinical/radiological), and stomas/proctectomies) could be demonstrated between the two periods.


This study showed a significantly reduced delay in diagnosis of CD in patients presenting with perianal disease by introducing a low threshold for diagnostic work-up for CD. The promising results of this study were reason to continue data collection in a larger prospective study (currently ongoing) that forms the basis for the international development of an evidence based clinical decision tool including a perianal Red Flag Index and calprotectin measurement to select those at risk of having CD. Reducing delay in diagnosis by using such a clinical decision tool may improve outcomes and QoL in patients with perianal Crohn de novo.