Crohn's disease

Background

  • Can involve any part of the GI tract from the mouth to the anus
  • Bimodal distribution: 15-22yr, 55-60yr
  • Pathology
    • All layers of the bowel are involved
      • Reason why fistulas and abscesses are common complications
    • "Skip lesions" are common

Diagnosis

GI Symptoms

  • Abdominal pain
  • Diarrhea
  • Wt loss
  • Perianal fissures or fistulas

Extraintestinal Symptoms (50%)

  • Arthritis
    • Peripheral arthritis
      • Migratory monarticular or polyarticular
    • Ankylosing spondylitis
      • Pain/stiffness of spine, hips, neck, rib cage
    • Sacroiliitis
    • Low back pain w/ morning stiffness
  • Ocular
    • Uveitis
      • Acute blurring of vision, photophobia, pain, perilimbic scleral injection
    • Episcleritis
      • Eye burning or itching w/o visual changes or pain; scleral and conj hyperemia
  • Dermatologic
    • Erythema nodosum
      • Painful, red, raised nodules on extensor surfaces of arms/legs
    • Pyoderma gangrenosum
      • Violacious, ulcerative lesions w/ necrotic center found in pretibial region or trunk
  • Hepatobiliary
    • Cholelithiasis (33%)
    • Fatty liver
    • Autoimmune hepatitis
    • Primary sclerosing cholangitis
    • Cholangiocarcinoma
  • Vascular
    • Thromboembolic disease

Work-Up

  • Labs
    • CBC
    • Chemistry
    • ESR/CRP
    • C.diff toxin
    • Type and Cross/Screen if any bleeding suspicion
  • Imaging:
    • Plain abdominal films - r/o obstruction, perforation and toxic megacolon
    • CT A/P
      • Most useful diagnostic test in pts w/ acute symptoms who have known or suspected Crohn
      • Findings: bowel wall thickening, mesenteric edema, local abscess, fistulas

DDx

  • Ulcerative colitis
  • Ischemic bowel disease
  • Pseudomembranous enterocolitis
  • Lymphoma
  • Ileocecal amebiasis
  • Sarcoidosis
  • Yersinia
  • Campylobacter

Management

Initial ED Management: IVF, bowel rest, analgesia, electrolyte correction, and NGT (if obstruction/ileus/toxic megacolon)

  • Rule-out complications:
    • Obstruction
      • Due to stricture or bowel wall edema
    • Abscess
      • Can be intraperitoneal, retroperitoneal, interloop, or intramesenteric
        • More severe abdominal pain than usual
        • Fever
        • Hip or back pain and difficulty walking (retroperitoneal abscess)
    • Fistula
      • Occurs due to extension of intestinal fissure into adjacent structures
      • Suspect if changes in pt's symptoms (e.g. BM frequency, amt of pain, wt loss)
    • Perianal disease
      • Abscess, fissures, fistulas, rectal prolapse
    • Hemorrhage
      • Erosion into a bowel wall vesel
    • Toxic megacolon
      • Can be associated w/ massive GI bleeding
  • Rule-out therapy complications:
    • Leukopenia /thrombocytopenia
    • Fever / infection
    • Pancreatitis
    • Renal / liver failure
  • Medications: Alterations should be discussed with GI
    • Aminosalicylates (5-ASA) - Mild-to-moderate Crohn's dz. Give with probiotics.
      • Sulfasalazine 3-5gm/day PO (sulfa drug)
        • Caution: Can cause folate deficiency so give with folic acid, and can cause hemolytic anemia in G6PD pts
      • Mesalamine 4gm/day PO
        • Active moiety of sulfasalazine, and formed from prodrug balsalazide
      • Balsalazide or Olsalazine - Bypasses small intestine to deliver drug into large intestine (better for UC)
    • Anti-diarrheal - Use caution in pts with active inflammation as can precipitate toxic megacolon
      • Loperamide 4-16mg/day
      • Diphenoxylate 5-20mg/day
      • Cholestyramine 4g once to six times daily
    • Glucocorticoids - Symptomatic relief (course not altered)
      • Prednisone - 40-60mg/day with taper once remission induced
      • Methylprednisolone 20mg IV q6hr
      • Hydrocortisone 100mg q8hr
        • Do not start if any suspicion of infection (ie C.diff colitis)
        • Double edge sword: Reduction of bone density in addition to underlying disease process(decreased Ca absorption)
    • Antibiotics - Induce remission
      • Ciprofloxacin 500mg q8-12hr OR
      • Metronidazole 500mg q6hr OR
      • Rifaximin 800mg BID
    • Immunomodulators - Steroid-sparing agents used in fistulas and pts w/ surgical contraindication. Slower onset.
      • 6-Mercaptopurine 1-1.5 mg/kg/day → Start at 50mg daily
      • Azathioprine 2-2.5mg/kg/day → Start at 50mg daily
      • Methotrexate IM
    • Anti-TNF - Medically resistant moderate-to-severe Crohn's dz
      • Infliximab (Remicade) 5mg/kg IV
      • Adalimumab (Humira), Natalizumab or certolizumab pegol can also be used

Disposition

Inpatient Admission

  • Metabolic derangements (ie electrolyte imbalance or severe dehydration)
  • Fulminate colitis
  • Obstruction
  • Peritonitis
  • Significant hemorrhage

===Surgical intervention Consult EARLY if any of the following suspicions

  • Perforation
  • Abscess/fistula formation
  • Toxic megacolon
  • Significant hemorrhage
  • Perianal disease
  • Failed medical management

See Also

References