Crohn disease is an idiopathic, chronic inflammatory process that can affect any part of the gastrointestinal tract from the mouth to the anus (see the image below). Individuals with this condition often experience periods of symptomatic relapse and remission.
Crohn disease. The colonoscopy image reveals a large ulcer and inflammation of the descending colon in a 12-year-old boy with Crohn disease.
See Autoimmune Disorders: Making Sense of Nonspecific Symptoms, a Critical Images slideshow, to help identify several diseases that can cause a variety of nonspecific symptoms.
Signs and symptoms
The characteristic presentation in Crohn disease is abdominal pain and diarrhea, which may be complicated by intestinal fistulization or obstruction. Unpredictable flares and remissions characterize the long-term course.
Other signs and symptoms of Crohn disease may include the following:
Weight loss, anorexia
Malnutrition, vitamin deficiencies
Psychosocial issues (eg, depression, anxiety, and coping difficulty); pediatric patients may also experience psychological issues regarding quality of life and body image
Growth failure in pediatric patients: May precede gastrointestinal symptoms by years
See Clinical Presentation for more detail.
Examination for Crohn disease includes the following:
Vital signs: Normal, but possible presence of tachycardia in anemic or dehydrated patients; possible chronic intermittent fever
Gastrointestinal: May vary from normal to those of an acute abdomen; assess for rectal sphincter tone, gross rectal mucosal abnormalities, presence of hematochezia
Genitourinary: May include presence of skin tags, fistulae, ulcers, abscesses, and scarring in the perianal region; nephrolithiasis, hydronephrosis, and enterovesical fistulae
Musculoskeletal: Possible arthritis and arthralgia, particularly of the large joints
Dermatologic: May show pallor or jaundice, mucocutaneous or aphthous ulcers, erythema nodosum, and pyoderma gangrenosum
Ophthalmologic: May reveal episcleritis; possible uveitis
Growth delay: Decreased growth velocity (eg, height), pubertal delay
Hematologic: Hypercoagulable state
Although laboratory results for Crohn disease are nonspecific and are of value principally for facilitating disease management, they may also be used as surrogate markers for inflammation and nutritional status and to screen for deficiencies of vitamins and minerals.
Routine laboratory studies include the following:
Liver function tests
Imaging modalities used for Crohn disease include the following:
Plain abdominal radiography
Barium contrast studies (eg, small bowel follow-through, barium enema, enteroclysis)
CT scanning of the abdomen
CT enterography or magnetic resonance enterography: Replacing small bowel follow-through studies
MRI of the pelvis
Abdominal and/or endoscopic ultrasonography
Nuclear imaging (eg, technetium-99m hexamethyl propylene amine oxime, indium-111)
Fluorine-18-2-fluoro-2-deoxy-D-glucose scanning combined with positron emission tomography or CT scanning
The following procedures may help in the evaluation of Crohn disease:
Endoscopic visualization and biopsy (eg, upper gastrointestinal endoscopy, esophagogastroduodenoscopy, endoscopic retrograde cholangiopancreatography)
Small bowel enteroscopy
Interventional radiology: For percutaneous drainages of abscesses
See Workup for more detail.
Medications used in the treatment of Crohn disease include the following:
5-Aminosalicylic acid derivative agents (eg, mesalamine rectal, mesalamine, sulfasalazine, balsalazide)
Corticosteroids (eg, prednisone, methylprednisolone, budesonide, hydrocortisone, prednisolone)
Immunosuppressive agents (eg, mercaptopurine, methotrexate, tacrolimus)
Monoclonal antibodies (eg, infliximab, adalimumab, certolizumab pegol, natalizumab, ustekinumab, vedolizumab)
Antibiotics (eg, metronidazole, ciprofloxacin)
Antidiarrheal agents (eg, loperamide, diphenoxylate-atropine)
Bile acid sequestrants (eg, cholestyramine, colestipol)
Anticholinergic agents (eg, dicyclomine, hyoscyamine, propantheline)
Unlike ulcerative colitis, Crohn disease has no surgical cure. Most patients with Crohn disease require surgical intervention during their lifetime.
Surgical management of the terminal ileum, ileocolon, and/or upper gastrointestinal tract may include the following
Resection of the affected bowel
Ileocolostomy or proximal loop ileostomy
Drainage of any septic foci with later definitive resection
Endoscopic dilatation of symptomatic, accessible strictures
Surgical management of the colon may include the following
Subtotal or total colectomy with end ileostomy (laparoscopic or open approach)
Segmental or total colectomy with or without primary anastomosis
Total proctocolectomy or proctectomy with stoma creation
See Treatment and Medication for more detail.