IBD, in full.

Two current US guidelines govern Crohn's disease and should be read together. ACG 2025 (Lichtenstein et al.) remains the reference for diagnosis, mild-to-moderate disease, perianal, postoperative and abscess management. DIAGNOSIS: fecal calprotectin (>50-100 μg/g) separates inflammatory from noninflammatory disease of the colon. Workup is ileocolonoscopy with biopsies, including uninvolved mucosa, plus small-bowel imaging. CTE and MRE are comparable; prefer MRE in patients <35 y and when serial exams are likely. Intestinal ultrasound is an ungraded adjunct. Do routine CRC surveillance in Crohn's colitis. MILD-TO-MODERATE: recommend against oral mesalamine; sulfasalazine only for symptomatic mild colonic CD; ileal-release budesonide 9 mg for induction in ileocecal disease but not for maintenance. MODERATE-TO-SEVERE (AGA Living Guideline, Scott et al., Gastroenterology 2025;169(7):1397-1448, 16 recommendations: 1 strong, 9 conditional, 6 knowledge gaps; updated quarterly, adult outpatients only): RECOMMEND infliximab, adalimumab, ustekinumab, risankizumab, mirikizumab, guselkumab or upadacitinib over no treatment; SUGGEST certolizumab pegol or vedolizumab over no treatment. Advanced-therapy-naive: suggest higher-efficacy agents (infliximab, adalimumab, vedolizumab, ustekinumab, risankizumab, mirikizumab, guselkumab) over lower-efficacy ones (certolizumab pegol, upadacitinib). Prior advanced-therapy (especially anti-TNF) exposure: suggest higher- or intermediate-efficacy agents (adalimumab, risankizumab, guselkumab, upadacitinib; ustekinumab, mirikizumab) over lower-efficacy ones (vedolizumab, certolizumab pegol). Suggest against thiopurine monotherapy for induction; suggest it for maintenance of remission. Suggest SC/IM methotrexate monotherapy; suggest against oral methotrexate. In thiopurine-naive patients starting infliximab, suggest infliximab + thiopurine over infliximab alone. No recommendation on IFX + MTX, adalimumab + immunomodulator, or non-TNF biologic + immunomodulator. After ≥6 months of steroid-free remission on anti-TNF + immunomodulator, suggest withdrawing the immunomodulator and suggest against withdrawing the anti-TNF. SUGGEST upfront advanced therapy over step-up therapy (corticosteroids and/or immunomodulator first). No recommendation on treating to endoscopic vs symptomatic remission. The ACG 2025 moderate-to-severe recommendations (anti-TNF, IFX + thiopurine combination and IL-12/23/IL-23 agents, each strong/moderate; upadacitinib after anti-TNF exposure; steroids for short-term induction only; TPMT/NUDT15 testing before thiopurines) still stand alongside AGA. ACG perianal (infliximab first; drain abscesses and place setons before escalating), postoperative (endoscopy at 6-12 months; anti-TNF strong, vedolizumab conditional in high-risk patients) and intra-abdominal abscess (>2 cm: antibiotics plus drainage, hold immunosuppression) positions are unchanged. THERAPEUTIC ENDOSCOPY (AGA Clinical Practice Update, CGH 2026; details below come from AGA news coverage, not the full text, and are ungraded advice): get cross-sectional imaging before the procedure. Endoscopic balloon dilation is first-line for short strictures (about ≤4-5 cm) with few risk factors (fistula, prestenotic dilation >5 cm, high CRP, prior anti-TNF). Longer or multiple strictures, or ≥3 risk factors, favor surgery.

Outpatient positioning is unchanged from the ACG 2025 UC guideline and the AGA living guideline for moderate-to-severe UC. Confirm UC with endoscopy showing continuous colonic inflammation from the rectum plus histology, after excluding infection with two-step C. difficile testing. Treat mild-moderate disease with 5-ASA chosen by route and extent: suppository for proctitis, enema for left-sided disease, oral plus rectal for extensive disease. If 5-ASA fails, treat as moderate-to-severe rather than stepping up gradually. Position advanced therapy by efficacy tier, not by an anti-TNF-first rule. Advanced-therapy-naive, higher efficacy: infliximab, vedolizumab, ozanimod, etrasimod, upadacitinib, risankizumab, guselkumab. Intermediate: golimumab, ustekinumab, tofacitinib, filgotinib, mirikizumab. Lower: adalimumab. Previously TNF-exposed, higher efficacy: tofacitinib, upadacitinib, ustekinumab. Lower: adalimumab, vedolizumab, ozanimod, etrasimod. After anti-TNF primary non-response, switch mechanism rather than cycling within the class. Treat to target (STRIDE-II): endoscopic improvement, Mayo endoscopic subscore 0-1. Begin CRC surveillance 8-10 years after diagnosis for extensive or left-sided disease; isolated proctitis follows average-risk screening. Inpatient care now follows the 2026 AGA Clinical Practice Update (13 best-practice statements). Admit for severe symptoms refractory to outpatient therapy, suspected complications (obstruction, abscess, toxic megacolon) or significant malnutrition, and identify acute severe UC by Truelove-Witts. Give every patient admitted with diarrhea two-step C. difficile testing. Test for CMV, with early endoscopy, if symptoms worsen, the patient is systemically toxic or disease is steroid-refractory. Give routine VTE prophylaxis with LMWH or fondaparinux unless contraindicated, and individualize post-discharge extension. Give IV methylprednisolone 60 mg/day or equivalent; the AGA living guideline says 40-60 mg/day, and higher doses add no benefit. Do not give adjunctive antibiotics without infection. Involve surgery early. Assess response by day 3 (72 h) using stool frequency and CRP (Oxford criteria); do not continue IV steroids beyond about 7 days without response. Rescue steroid non-responders with infliximab (accelerated or intensified dosing in selected patients with high inflammatory burden or protein-losing colopathy), cyclosporine, or a JAK inhibitor at standard or intensified dosing, or with colectomy. Before discharge, the response should be stable and a transition plan should be in place.

Two current US guidelines govern Crohn's disease and should be read together. ACG 2025 (Lichtenstein et al.) remains the reference for diagnosis, mild-to-moderate disease, perianal, postoperative and abscess management. DIAGNOSIS: fecal calprotectin (>50-100 μg/g) separates inflammatory from noninflammatory disease of the colon. Workup is ileocolonoscopy with biopsies, including uninvolved mucosa, plus small-bowel imaging. CTE and MRE are comparable; prefer MRE in patients <35 y and when serial exams are likely. Intestinal ultrasound is an ungraded adjunct. Do routine CRC surveillance in Crohn's colitis. MILD-TO-MODERATE: recommend against oral mesalamine; sulfasalazine only for symptomatic mild colonic CD; ileal-release budesonide 9 mg for induction in ileocecal disease but not for maintenance. MODERATE-TO-SEVERE (AGA Living Guideline, Scott et al., Gastroenterology 2025;169(7):1397-1448, 16 recommendations: 1 strong, 9 conditional, 6 knowledge gaps; updated quarterly, adult outpatients only): RECOMMEND infliximab, adalimumab, ustekinumab, risankizumab, mirikizumab, guselkumab or upadacitinib over no treatment; SUGGEST certolizumab pegol or vedolizumab over no treatment. Advanced-therapy-naive: suggest higher-efficacy agents (infliximab, adalimumab, vedolizumab, ustekinumab, risankizumab, mirikizumab, guselkumab) over lower-efficacy ones (certolizumab pegol, upadacitinib). Prior advanced-therapy (especially anti-TNF) exposure: suggest higher- or intermediate-efficacy agents (adalimumab, risankizumab, guselkumab, upadacitinib; ustekinumab, mirikizumab) over lower-efficacy ones (vedolizumab, certolizumab pegol). Suggest against thiopurine monotherapy for induction; suggest it for maintenance of remission. Suggest SC/IM methotrexate monotherapy; suggest against oral methotrexate. In thiopurine-naive patients starting infliximab, suggest infliximab + thiopurine over infliximab alone. No recommendation on IFX + MTX, adalimumab + immunomodulator, or non-TNF biologic + immunomodulator. After ≥6 months of steroid-free remission on anti-TNF + immunomodulator, suggest withdrawing the immunomodulator and suggest against withdrawing the anti-TNF. SUGGEST upfront advanced therapy over step-up therapy (corticosteroids and/or immunomodulator first). No recommendation on treating to endoscopic vs symptomatic remission. The ACG 2025 moderate-to-severe recommendations (anti-TNF, IFX + thiopurine combination and IL-12/23/IL-23 agents, each strong/moderate; upadacitinib after anti-TNF exposure; steroids for short-term induction only; TPMT/NUDT15 testing before thiopurines) still stand alongside AGA. ACG perianal (infliximab first; drain abscesses and place setons before escalating), postoperative (endoscopy at 6-12 months; anti-TNF strong, vedolizumab conditional in high-risk patients) and intra-abdominal abscess (>2 cm: antibiotics plus drainage, hold immunosuppression) positions are unchanged. THERAPEUTIC ENDOSCOPY (AGA Clinical Practice Update, CGH 2026; details below come from AGA news coverage, not the full text, and are ungraded advice): get cross-sectional imaging before the procedure. Endoscopic balloon dilation is first-line for short strictures (about ≤4-5 cm) with few risk factors (fistula, prestenotic dilation >5 cm, high CRP, prior anti-TNF). Longer or multiple strictures, or ≥3 risk factors, favor surgery.

Suspected small-bowel bleeding (SSBB), bleeding between the ampulla of Vater and the ileocecal valve, suspected when GI bleeding persists after negative upper and lower endoscopy. Small-bowel capsule endoscopy (SBCE) is recommended as the FIRST-LINE examination, before other endoscopic and radiological tests (strong, moderate). ESGE does NOT recommend routine second-look endoscopy prior to SBCE in suspected small-bowel bleeding or iron-deficiency anemia (strong, low). In OVERT suspected small-bowel bleeding, perform SBCE as soon as possible after the bleeding episode, ideally within 48 hours, to maximize diagnostic and therapeutic yield (strong, high). Device-assisted enteroscopy (DAE) is recommended to confirm and possibly treat lesions identified by SBCE (strong, high); in overt suspected small-bowel bleeding, DAE should optimally be performed within 48-72 hours of the bleeding episode (strong, high). Where SBCE is unavailable or contraindicated, DAE and/or dedicated small-bowel cross-sectional imaging may be considered first, depending on availability, expertise and clinical suspicion (weak, low). After a HIGH-QUALITY NEGATIVE SBCE, ESGE recommends conservative management (strong, moderate), the 2015 wording qualified this as patients without ongoing bleeding evidenced by overt bleeding or continued transfusion requirement, and the 2022 update carries this qualifier as a separate companion recommendation: for patients with a high-quality negative SBCE who have ONGOING overt bleeding or a continued need for blood transfusions, ESGE recommends further investigation using repeat SBCE, DAE, or dedicated small-bowel cross-sectional imaging (strong, moderate). SBCE is also recommended first-line in iron-deficiency anemia when small-bowel evaluation is indicated (strong, high), and after unremarkable or nondiagnostic dedicated small-bowel cross-sectional imaging if likely to influence management (strong, low). CROHN'S DISEASE: in SUSPECTED Crohn's with negative ileocolonoscopy, SBCE is the initial small-bowel modality ONLY in the absence of obstructive symptoms or known bowel stenosis (strong, high); in that group ESGE explicitly does NOT recommend routine cross-sectional imaging or a patency capsule before SBCE (strong, HIGH quality). With obstructive symptoms or known stenosis, dedicated cross-sectional imaging (MRE/MR-enteroclysis or CTE/CT-enteroclysis) is used FIRST (strong, moderate), and a patency capsule is recommended before SBCE in suspected Crohn's with obstructive symptoms (strong, low), even when cross-sectional imaging is negative. In ESTABLISHED Crohn's, a patency capsule before SBCE is recommended to decrease the retention rate (strong, moderate). SMALL-BOWEL TUMORS: SBCE is recommended where there is increased risk of a small-bowel tumor (strong, moderate); ESGE does NOT recommend specific investigations before SBCE in suspected small-bowel tumor UNLESS the patient is considered at risk of capsule retention (strong, low). If imaging has ALREADY demonstrated a suspected small-bowel tumor, DAE is preferred over SBCE (strong, low). Cross-sectional imaging is recommended for staging and operability when SBCE shows a tumor with high diagnostic certainty (strong, low); where the capsule diagnosis is uncertain, biopsy sampling AND tattooing of the location by DAE is recommended (strong, low); for a subepithelial mass, confirm by DAE and/or cross-sectional imaging per local availability/expertise (strong, low). SBCE is NOT recommended for follow-up of treated small-bowel tumors, for lack of data (strong, low). PATENCY/RETENTION generally: GI obstruction is an absolute contraindication to SBCE. If the patency capsule is egested intact, retention of a real capsule is unlikely; if not egested within 30 hours, cross-sectional imaging (not plain abdominal radiography) is favored to localize it. In Peutz-Jeghers syndrome, routine patency capsule use is NOT recommended and should be considered case-by-case.

Outpatient positioning is unchanged from the ACG 2025 UC guideline and the AGA living guideline for moderate-to-severe UC. Confirm UC with endoscopy showing continuous colonic inflammation from the rectum plus histology, after excluding infection with two-step C. difficile testing. Treat mild-moderate disease with 5-ASA chosen by route and extent: suppository for proctitis, enema for left-sided disease, oral plus rectal for extensive disease. If 5-ASA fails, treat as moderate-to-severe rather than stepping up gradually. Position advanced therapy by efficacy tier, not by an anti-TNF-first rule. Advanced-therapy-naive, higher efficacy: infliximab, vedolizumab, ozanimod, etrasimod, upadacitinib, risankizumab, guselkumab. Intermediate: golimumab, ustekinumab, tofacitinib, filgotinib, mirikizumab. Lower: adalimumab. Previously TNF-exposed, higher efficacy: tofacitinib, upadacitinib, ustekinumab. Lower: adalimumab, vedolizumab, ozanimod, etrasimod. After anti-TNF primary non-response, switch mechanism rather than cycling within the class. Treat to target (STRIDE-II): endoscopic improvement, Mayo endoscopic subscore 0-1. Begin CRC surveillance 8-10 years after diagnosis for extensive or left-sided disease; isolated proctitis follows average-risk screening. Inpatient care now follows the 2026 AGA Clinical Practice Update (13 best-practice statements). Admit for severe symptoms refractory to outpatient therapy, suspected complications (obstruction, abscess, toxic megacolon) or significant malnutrition, and identify acute severe UC by Truelove-Witts. Give every patient admitted with diarrhea two-step C. difficile testing. Test for CMV, with early endoscopy, if symptoms worsen, the patient is systemically toxic or disease is steroid-refractory. Give routine VTE prophylaxis with LMWH or fondaparinux unless contraindicated, and individualize post-discharge extension. Give IV methylprednisolone 60 mg/day or equivalent; the AGA living guideline says 40-60 mg/day, and higher doses add no benefit. Do not give adjunctive antibiotics without infection. Involve surgery early. Assess response by day 3 (72 h) using stool frequency and CRP (Oxford criteria); do not continue IV steroids beyond about 7 days without response. Rescue steroid non-responders with infliximab (accelerated or intensified dosing in selected patients with high inflammatory burden or protein-losing colopathy), cyclosporine, or a JAK inhibitor at standard or intensified dosing, or with colectomy. Before discharge, the response should be stable and a transition plan should be in place.

Two current US guidelines govern Crohn's disease and should be read together. ACG 2025 (Lichtenstein et al.) remains the reference for diagnosis, mild-to-moderate disease, perianal, postoperative and abscess management. DIAGNOSIS: fecal calprotectin (>50-100 μg/g) separates inflammatory from noninflammatory disease of the colon. Workup is ileocolonoscopy with biopsies, including uninvolved mucosa, plus small-bowel imaging. CTE and MRE are comparable; prefer MRE in patients <35 y and when serial exams are likely. Intestinal ultrasound is an ungraded adjunct. Do routine CRC surveillance in Crohn's colitis. MILD-TO-MODERATE: recommend against oral mesalamine; sulfasalazine only for symptomatic mild colonic CD; ileal-release budesonide 9 mg for induction in ileocecal disease but not for maintenance. MODERATE-TO-SEVERE (AGA Living Guideline, Scott et al., Gastroenterology 2025;169(7):1397-1448, 16 recommendations: 1 strong, 9 conditional, 6 knowledge gaps; updated quarterly, adult outpatients only): RECOMMEND infliximab, adalimumab, ustekinumab, risankizumab, mirikizumab, guselkumab or upadacitinib over no treatment; SUGGEST certolizumab pegol or vedolizumab over no treatment. Advanced-therapy-naive: suggest higher-efficacy agents (infliximab, adalimumab, vedolizumab, ustekinumab, risankizumab, mirikizumab, guselkumab) over lower-efficacy ones (certolizumab pegol, upadacitinib). Prior advanced-therapy (especially anti-TNF) exposure: suggest higher- or intermediate-efficacy agents (adalimumab, risankizumab, guselkumab, upadacitinib; ustekinumab, mirikizumab) over lower-efficacy ones (vedolizumab, certolizumab pegol). Suggest against thiopurine monotherapy for induction; suggest it for maintenance of remission. Suggest SC/IM methotrexate monotherapy; suggest against oral methotrexate. In thiopurine-naive patients starting infliximab, suggest infliximab + thiopurine over infliximab alone. No recommendation on IFX + MTX, adalimumab + immunomodulator, or non-TNF biologic + immunomodulator. After ≥6 months of steroid-free remission on anti-TNF + immunomodulator, suggest withdrawing the immunomodulator and suggest against withdrawing the anti-TNF. SUGGEST upfront advanced therapy over step-up therapy (corticosteroids and/or immunomodulator first). No recommendation on treating to endoscopic vs symptomatic remission. The ACG 2025 moderate-to-severe recommendations (anti-TNF, IFX + thiopurine combination and IL-12/23/IL-23 agents, each strong/moderate; upadacitinib after anti-TNF exposure; steroids for short-term induction only; TPMT/NUDT15 testing before thiopurines) still stand alongside AGA. ACG perianal (infliximab first; drain abscesses and place setons before escalating), postoperative (endoscopy at 6-12 months; anti-TNF strong, vedolizumab conditional in high-risk patients) and intra-abdominal abscess (>2 cm: antibiotics plus drainage, hold immunosuppression) positions are unchanged. THERAPEUTIC ENDOSCOPY (AGA Clinical Practice Update, CGH 2026; details below come from AGA news coverage, not the full text, and are ungraded advice): get cross-sectional imaging before the procedure. Endoscopic balloon dilation is first-line for short strictures (about ≤4-5 cm) with few risk factors (fistula, prestenotic dilation >5 cm, high CRP, prior anti-TNF). Longer or multiple strictures, or ≥3 risk factors, favor surgery.