Gastroenterology
Crohn Disease
크론병
Transmural granulomatous IBD anywhere from mouth to anus
- How common
- 50–100 per 100,000
- Typical age
- Peak ages 15–30
What is it?
NOD2/CARD15 genetics, smoking, Th1/Th17 immune response cause transmural granulomatous inflammation anywhere in GI tract.
Commonly affected: Terminal ileum/right colon predominant (anywhere in GI)
How it develops
- Genetic/environmentalNOD2/CARD15 mutation; smoking is risk factor
- Barrier/microbiomeAberrant response to commensal bacteria
- Th1/Th17 immunityIFN-γ, IL-17, TNFα mediated
- Transmural granulomatous inflammationStrictures, fistulas, abscesses form
Symptoms
- Perianal fistula/abscessPathognomonic complication
- Chronic pain/diarrheaRLQ, non-bloody diarrhea
- Weight loss/feverResult of systemic inflammation
- Stricture/obstructionPostprandial pain/vomiting
- Aphthous ulcers/arthritisExtraintestinal manifestations
How it is examined
- Abdominal examRLQ mass or tenderness
- Perianal examCheck for fistula, abscess, fissure
- Ileocolonoscopy + biopsyConfirm non-caseating granulomas
Imaging
SBFT or CT/MR enterography for stricture, fistula, transmural disease.
- String sign
- Fistula/abscess
- Wall thickening
Colonoscopy shows skip lesions, aphthous ulcers, cobblestoning.
- Skip lesions
- Deep linear ulcers
- Cobblestoning
Non-surgical care
- Mild: budesonideEffective for ileocecal disease
- Moderate: immunomodulatorAzathioprine, 6-MP, methotrexate
- BiologicsInfliximab, adalimumab (anti-TNF), ustekinumab (IL-12/23), vedolizumab (α4β7)
- AntibioticsCiprofloxacin/metronidazole for fistula/abscess
- Nutrition/smoking cessationEnteral nutrition (peds); smoking is major risk
Conservative options are generally tried first. Medications listed here can have side effects — discuss them with your prescriber.
When surgery is considered
Stricture, fistula, abscess, perforation, medical failure
Procedures that may be discussed
- Strictureplasty
- Ileocecal resection
- Fistulotomy + seton drainage
Outlook
Relapsing course; 70% need surgery at least once. Biologics improve remission rates.