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Background Peri-anal sepsis may represent the first manifestation of Crohn’s disease, and diagnostic delay is associated with worse long-term outcomes. Recent consensus recommendations from the Top-Class (PREFAB) Consortium propose a structured diagnostic pathway to facilitate earlier identification of Crohn’s disease in this setting; however, real-world implementation remains uncertain.Methods Retrospective analysis of all adult (≥18 years) patients within a single NHS trust who underwent an emergency incision and drainage of peri-anal abscess from October 2020 – October 2025. Patients with a pre-existing diagnosis of inflammatory bowel disease (IBD) were excluded. Electronic records were reviewed for adherence to the Top-Class diagnostic pathway, including whether a faecal calprotectin (FC) was checked and presence of any high-risk criteria (weight loss, diarrhoea, primary sclerosing cholangitis, recurrent fistulation, fistulation involving other organs, proctitis, anal stenosis). In patients meeting high-risk criteria or with elevated FC (>150 µg/g), subsequent colonoscopy and Crohn’s diagnosis were assessed.Results Of 260 procedures, 239 unique patients were analysed following exclusion of those with pre-existing IBD (n=5) and repeat procedures (n=16). Seven patients (2.9%) were subsequently diagnosed with Crohn’s disease. FC was measured in 20 patients (8.4%), of whom 8 had values ≥150 µg/g. Thirty-six patients (15.1%) met at least one high-risk clinical criterion. In total, 44 patients were classified as high-risk. Of these, 25 (56.8%) underwent colonoscopy, with terminal ileal intubation achieved in 9 (36%). Six patients (13.6% of high-risk group) were subsequently diagnosed with Crohn’s disease, with median time to diagnosis (inter-quartile range) of 13 months (1-26 months). Among the remaining 195 patients without FC testing or high-risk features, one (0.5%) was subsequently diagnosed with Crohn’s disease at 18 months.Conclusion This audit demonstrates poor adherence to Top-Class guidance, particularly the low use of FC testing and incomplete investigation of high-risk patients. Despite this, the vast majority of Crohn’s disease diagnoses arose from the high-risk cohort. These findings suggest that clinical risk stratification is an effective triage approach in patients presenting with perianal sepsis, while routine FC testing in low-risk patients may have limited additional value.