Crohn disease
From IDWiki
Differential Diagnosis
- Irritable bowel syndrome (IBS)
- Lactose intolerance
- Infectious colitis
- Bacteria
- Shigella, Salmonella, Campylobacter, Escherichia coli O157:H7, Yersinia
- Clostridium difficile
- Ileocecal tuberculosis
- Chlamydria (more common), syphilis, and gonorrhea
- Protozoa
- Parasites, including Giardia
- Ileocecal amebiasis
- Viruses
- CMV (in immunocompromised)
- Common variable immunodeficiency (CVID)
- Bacteria
- Ulcerative colitis: from rectum extending proximally
- Others: appendicitis, diverticulitis, ischemic colitis, carcinoma with obstruction, lymphoma, chronic mesenteric ischemia, endometriosis, and carcinoid
Comparison to UC
| Feature | Crohn | UC |
|---|---|---|
| Symptoms | Abdo pain/cramping, diarrhea +/- blood | Tenesmus, bloody stool, mucous |
| Distribution | Discontinuous with skip lesions; 80% TI, 50% ileocolonic, 30% isolated ileal, 20% isolated colonic | Continuous; 30% pancolitis, 50% proctosigmoiditis |
| Muscosa | Transmural inflammation | Mucosal inflammation |
| Extraintestinal manifestations | More skin (pyoderma, EN), arthritis, osteopenia, fistulas, strictures | More PSC, more ophtho, arthritis, osteopenia |
Clinical Presentation
- Diarrhea frequency, consistency, bloody, steatorrhea
- Ileitis and Colitis: diarrhea, abdominal pain, weight loss, fever
- Crampy abdominal pain
- Bleeding less common than UC
- Fistulae: enteroenteric, enterovesicular, fistulae to psoas abscess
- Associated symptoms: aphthous ulcers, dysphagia, odynophagia, gastric outlet obstruction, fat malabsorption and steatorrhea, perianal disease
History
- Consider other causes
- Food poisoning: restaurant, foods
- Infectious: travel history, contacts, HIV risk factors, Yersinia, TB
- Ischemic: CAD and cardiac risk factors
- Drug induced: recent antibiotics
- Complications of IBD
- General: fever/chills/weight loss
- HEENT: eye for uveitis, episcleritis
- Chest: pulmonary fibrosis
- GI: PSC with elevated ALP, steatorrhea causing malnutrition, Vit D deficiency
- Massive hemorrhage, acute perforation, fistula, abscess, toxic megacolon
- Renal: oxalate stones due to increased oxalate absorption (Ca bound to free fatty acids)
- MSK: arthritis (large joints, ank spondylitis), osteoporosis
- Skin: erythema nodosum, pyoderma gangrenosum
- Heme: venous thromboembolism, vit B12 deficiency (ileal disease)
- PMH, Meds, Allergies, Smoking, Alcohol
- Family history of IBD
Physical
- Vitals: may be volume depleted or febrile
- H&N: uveitis, episcleritis, oral ulcers, lymphadenopathy
- Resp: pulmonary fibrosis
- GI: abdo pain, liver, jaundice, spleen, masses, acute abdomen
- MSK: arthritis, osteoporosis
- Skin: erythema nodosum, pyoderma gangrenosum
Management
- Mild
- Colonic: sulfasalazine
- Ileocolic: controlled-release budesonide
- Azathioprine or methotrexate for maintenance
- Fistulas
- Infliximab or other anti-TNF-alpha biologic
- Add antibiotics for perianal fistulas
- May be able to use antibiotics alone for simple fistulas
- Infliximab or other anti-TNF-alpha biologic
- Active
- Oral corticosteroids for remission followed by azathioprine for maintenance
- Can also consider methotrexate for maintenance
- If refractory, use infliximab
- Oral corticosteroids for remission followed by azathioprine for maintenance
Further Reading
- ACG Guidelines for the Management of Crohn’s Disease in Adults. Am J Gastroenterol. 2018 Apr;113(4):481-517.
- AGA Guideline on the Management of Crohn’s Disease After Surgical Resection. Gastroenterology. 2017 Jan;152(1):271-275.
- CAG Clinical Practice Guidelines: The use of tumour necrosis factor-alpha antagonist therapy in Crohn’s disease. Can J Gastroenterol. 2009 Mar;23(3):185-202.
