351.4 ð ç« æ«éèš Summary
351.4.1 ð äžå¥è©±çžœçµ
IBD includes Crohnâs disease (CD) + ulcerative colitis (UC) â autoimmune chronic relapsing-remitting GI inflammation; 0.5% prevalence Western, increasing globallyïŒCDïŒtransmural inflammation + skip lesions + any GI tract (ileum + colon most) + fistula/stricture/abscess complications + granulomas + smoking worsensïŒUCïŒmucosal inflammation + continuous from rectum proximally + colorectum only + bloody diarrhea hallmark + no granulomas + smoking protective + colectomy curativeïŒpresentationïŒbloody diarrhea + cramping + weight loss + extraintestinal manifestations (joints #1 â type 1/type 2/AS; skin EN/PG/Sweet; eye uveitis; PSC strongly UC-associated; renal oxalate stones CD; hematologic anemia/hypercoagulable)ïŒdiagnosisïŒcolonoscopy + ileal intubation + biopsy (gold standard) + fecal calprotectin + MR enterography (MRE) for CD; pANCA (UC), ASCA (CD)ïŒtreatment 2024 paradigmïŒ(1) 5-ASA (mesalamine) UC mild-moderate mainstay; (2) corticosteroids for induction (not maintenance); (3) immunomodulators (thiopurines AZA/6-MP, methotrexate) for maintenance; (4) biologics era â anti-TNF (infliximab/adalimumab/certolizumab/golimumab), anti-integrin (vedolizumab gut-selective), anti-IL-12/23 (ustekinumab), anti-IL-23 selective (risankizumab FDA 2022 CD/2024 UC, mirikizumab FDA 2023 UC, guselkumab emerging), JAK inhibitors (tofacitinib UC, upadacitinib UC+CD), S1P modulators (ozanimod FDA 2021, etrasimod FDA 2023); top-down approach for moderate-severe; treat-to-target mucosal healing; toxic megacolon (severe UC) â IV steroids + abx + cyclosporine/infliximab rescue + colectomy; perianal fistulizing CD â infliximab + drainage/setons; UC colectomy curative; CRC surveillance every 1-2 yr after 8-10 yr disease; pregnancy continue biologics, stop methotrexate; pouchitis post-IPAA â metronidazole + ciproã
351.4.2 ð æ²»ç粟èŠ
- mild-moderate UCïŒ5-ASA (mesalamine, sulfasalazine) oral + topical (suppositories, enemas) for distal disease + topical corticosteroids (budesonide) for active disease
- moderate-severe IBDïŒsystemic corticosteroids (prednisone, IV methylpred) for induction (not maintenance) + immunomodulators (thiopurines AZA/6-MP with TPMT testing, methotrexate for CD) for maintenance + biologics
- biologics & small molecules (2024)ïŒ
- anti-TNFïŒinfliximab, adalimumab, certolizumab, golimumab (UC); pre-treatment TB + HBV screen
- vedolizumab (Entyvio) anti-integrin gut-selective
- ustekinumab (Stelara) anti-IL-12/23
- risankizumab (Skyrizi) anti-IL-23p19 â CD FDA 2022 + UC FDA 2024
- mirikizumab (Omvoh) anti-IL-23 â UC FDA 2023
- tofacitinib (Xeljanz) + upadacitinib (Rinvoq) JAK inhibitors â UC + CD; black box CV/thrombotic events
- ozanimod (Zeposia) + etrasimod (Velsipity) S1P modulators â UC oral options
- toxic megacolonïŒIV steroids + broad antibiotics + cyclosporine or infliximab rescue + colectomy if refractory 24-72 h
- perianal fistulizing CDïŒinfliximab (best evidence) + surgical drainage + setons + combination immunomodulator + selected surgery
- UC colectomy with IPAA (J-pouch) curative for UC; pouchitis treated with metronidazole + ciprofloxacin
- CD surgery not curative: limited resection for complications + strictureplasty + endoscopic balloon dilation
- pregnancy + IBD: continue TNF inhibitors through pregnancy + stop methotrexate (teratogenic) + plan with specialist
- CRC surveillance: colonoscopy q 1-2 yr starting 8-10 yr after disease onset (earlier with PSC)
351.4.3 ð¯ ç§é«åž«çèåæé
- CD vs UC éå¥å¿ èïŒCD transmural + skip lesions + any GI (ileocolic most) + fistula/stricture + granulomas + smoking worsens; UC mucosal + continuous from rectum + colorectum only + bloody diarrhea + no granulomas + smoking protective + colectomy curative
- PSC strongly UC-associated (especially pancolitis with positive ANCA); increases CRC + cholangiocarcinoma risk; monitor CA 19-9
- fecal calprotectin > 250 suggests IBD activity (vs IBS); useful for monitoring + screening; CRP also helpful but less specific
- MR enterography (MRE) preferred for CD evaluation (small bowel, fistula characterization); CT enterography alternative; US emerging
- biologic era 2010s-2024 revolutionïŒanti-TNF first generation â vedolizumab (gut-selective) â ustekinumab (IL-12/23) â anti-IL-23 selective (risankizumab, mirikizumab) + JAK inhibitors (tofacitinib, upadacitinib) + S1P modulators (ozanimod, etrasimod) 2021-2024
- anti-IL-23 selective newer agentsïŒrisankizumab (Skyrizi) CD FDA 2022 + UC FDA 2024; mirikizumab (Omvoh) UC FDA 2023; potentially better safety than broader anti-IL-12/23 (ustekinumab)
- JAK inhibitor black box warningïŒCV events + thrombotic + malignancy + mortality (especially ⥠50, RA history, smokers, tofacitinib > upadacitinib); careful patient selection + monitoring (lipids, CBC, infection)
- S1P modulators (ozanimod, etrasimod) for UC oral optionsïŒsphingosine-1-phosphate receptor modulator â lymphocyte sequestration in lymph nodes; first-dose bradycardia + macular edema + lymphopenia monitoring
- top-down approach for moderate-severe IBDïŒearly biologic + immunomodulator combo (vs traditional step-up); SONIC trial in CD showed infliximab + AZA superior; reduces complications + surgery
- CRC surveillance in IBDïŒcolonoscopy every 1-2 years starting 8-10 years after disease onset (UC and CD-colitis); earlier and more frequent with PSC; random + targeted (chromoendoscopy) biopsies; confirmed dysplasia â colectomy consideration