Clinical decision support

Practice guidelines and risk calculators

Third-party guidelines and prediction tools relevant to Crohn’s disease, each independently verified against PubMed. These are external documents and tools — linked, not reproduced, and not evidence-gated by this site.

Practice guidelines

• ECCO Guidelines on Therapeutics in Crohn's Disease: Surgical Treatment ECCO · 2024 · PMID 38878002 · J Crohns Colitis
  When and how to operate: operative indications, preoperative drug management/optimisation, anastomotic technique, stricturing and penetrating disease, and combined medical-surgical management of perianal fistulising CD (introduces a severity/patient-goal stratification). Supersedes the 2018 ECCO-ESCP Consensus on Surgery for Crohn's Disease.
• The American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the Surgical Management of Crohn's Disease ASCRS · 2020 · PMID 32692069 · Dis Colon Rectum
  28 graded recommendations across operative indications, technique, and postoperative medical therapy — the primary US colorectal-surgical reference. CAVEAT: still the guideline ASCRS lists as current (confirmed no CD replacement; ASCRS's 2026 revision was for ulcerative colitis, DCR 69(8):2012-2039), but it is past ASCRS's nominal 5-year revision cycle and predates risankizumab/mirikizumab/guselkumab/upadacitinib.
• ECCO Guidelines on Therapeutics in Crohn's Disease: Medical Treatment ECCO · 2024 · PMID 38877997 · J Crohns Colitis
  Drug selection and sequencing for induction/maintenance, combination therapy, therapeutic drug monitoring and dietary strategies. Companion document to the ECCO surgical guideline; the two are designed to be read together.
• ACG Clinical Guideline: Management of Crohn's Disease in Adults ACG · 2025 · PMID 40701562 · Am J Gastroenterol
  Full-spectrum adult CD: diagnostics/biomarkers, luminal, stricturing and fistulising phenotypes, CRC surveillance in Crohn's colitis. Replaces the 2018 ACG guideline; notably drops the requirement to fail conventional therapy before advanced therapy.
• AGA Living Clinical Practice Guideline on the Pharmacologic Management of Moderate-to-Severe Crohn's Disease AGA · 2025 · PMID 41274746 · Gastroenterology
  16 recommendations on positioning of advanced therapies, early advanced therapy vs step-up, combination therapy, de-escalation, and treating to endoscopic vs clinical remission. CAVEAT: cite alongside its erratum (Gastroenterology 2026;170(2):441). Living format — the panel reviewed new evidence in March 2026 and issued no changes.
• British Society of Gastroenterology guidelines on inflammatory bowel disease in adults: 2025 BSG · 2025 · PMID 40550582 · Gut
  Comprehensive UK adult IBD guideline (101 pp.) replacing the 2019 BSG version; GRADE tables for CD induction/maintenance, faecal calprotectin interpretation, and service standards. Derivative condensed 'Part 1 – Crohn's disease' review articles exist but the Gut supplement is the primary document.
• American Gastroenterological Association Institute Guideline on the Management of Crohn's Disease After Surgical Resection AGA · 2017 · PMID 27840074 · Gastroenterology
  The only dedicated guideline on postoperative recurrence prophylaxis: early pharmacologic prophylaxis over endoscopy-guided treatment, anti-TNF and/or thiopurines preferred, ileocolonoscopy at 6–12 months. CAVEAT: still AGA's active guidance (no superseding AGA document found) but it is from 2017, restricted to asymptomatic patients with an accessible ileocolonic anastomosis and no residual disease, and predates every post-2017 agent; ECCO 2024 surgical and ACG 2025 are more current on the same question.
• AGA Clinical Practice Guideline on the Role of Biomarkers for the Management of Crohn's Disease AGA · 2023 · PMID 37981354 · Gastroenterology
  How to use faecal calprotectin and CRP instead of, or before, endoscopy — including detection of postoperative endoscopic recurrence (modified Rutgeerts ≥i2) in the surgically induced remission population. The practical companion to the postoperative monitoring recommendations.
• ECCO-ESGAR-ESP-IBUS Guideline on Diagnostics and Monitoring of Patients with Inflammatory Bowel Disease: Part 1 ECCO / ESGAR / ESP / IBUS · 2025 · PMID 40741688 · J Crohns Colitis
  Joint gastroenterology–radiology–pathology–ultrasound guideline on how to establish diagnosis and monitor disease: cross-sectional imaging, intestinal ultrasound, endoscopy and histology. The reference for characterising a stricture as inflammatory vs fibrotic before choosing dilation, strictureplasty or resection.
• ESPEN guideline on Clinical Nutrition in inflammatory bowel disease ESPEN · 2023 · PMID 36739756 · Clin Nutr
  71 recommendations on nutritional assessment, exclusive enteral nutrition, perioperative nutritional optimisation and micronutrient management — the evidence base for prehabilitation before Crohn's resection. Note the shorter 'practical' ESPEN version is still the 2020 edition; this 2023 scientific guideline is the current full document.

Risk calculators and prediction tools

• ACS NSQIP Surgical Risk Calculator (v4.0.4) live calculatorexternally validatedPredicts risk of death and of specific 30-day postoperative complications (serious complication, SSI, pneumonia, VTE, readmission, discharge to nursing facility, length of stay) from preoperative variables plus CPT code. Note: Externally validated in general surgical populations, NOT calibrated for Crohn's disease. It has no field for corticosteroid DOSE or duration, biologic/small-molecule exposure, penetrating vs stricturing phenotype, preoperative abscess, hypoalbuminaemia as a graded variable, number of prior resections, or nutritional status — i.e. it omits most of what actually drives risk in a Crohn's resection. Use it as a generic perioperative baseline for consent, never as a Crohn's-specific risk estimate.
• Postoperative Crohn's disease recurrence nomogram (Allez et al., biologic era) paywalledexternally validatedPredicts endoscopic recurrence (modified Rutgeerts score ≥i2b) within the first year after ileocolonic resection; the same cohort reports long-term clinically significant recurrence of 22.9% / 36.5% / 53.2% at 3 / 5 / 10 years. · PMID 41905522 Note: The best-validated postoperative recurrence tool available (prospective multicentre derivation, n=632, plus 2 independent international validation cohorts) — but discrimination is only modest, AUC 0.72, so it stratifies groups rather than resolving individual cases. The endpoint is 1-year ENDOSCOPIC recurrence, a surrogate for surgical recurrence. Published March 2026, so independent replication beyond the authors' own validation cohorts does not yet exist. There is no hosted implementation: the nomogram must be read off the figure in the paywalled paper.
• Nomogram for postoperative intra-abdominal septic complications after bowel resection and primary anastomosis in Crohn's disease (Zhu et al.) paywalledderivation cohort onlyPredicts intra-abdominal septic complications (anastomotic leak, intra-abdominal abscess, enterocutaneous fistula) after CD bowel resection with primary anastomosis — i.e. informs the decision to divert. · PMID 32032204 Note: DERIVATION ONLY — the authors themselves state that 'a major limitation of this model is the lack of external validation', so the reported AUC of 0.823 is apparent performance and will be optimistic. Single-centre Chinese cohort (n=949, 2011–2017) in which preoperative exclusive enteral nutrition was routine and strongly protective (OR 0.19); that practice pattern does not transfer to most Western centres, so the model's calibration elsewhere is unknown. Biologic exposure is captured only as infliximab. Do not use it to justify or to withhold a diverting stoma without local recalibration.