Overview
What are the signs and symptoms of Crohn disease?
Which physical exams should be performed if Crohn disease is suspected?
Which routine lab studies are useful in the diagnosis and management of Crohn disease?
Which imaging studies are useful for Crohn disease?
Which procedures may be useful in the evaluation of Crohn disease?
Which medications are used in the treatment of Crohn disease?
Which surgical procedures may be performed for the management of Crohn disease?
Which factors may trigger Crohn disease?
Which parts of the GI tract are involved in Crohn disease?
What are the characteristics of Crohn disease?
What is the role of lab tests in Crohn disease?
Which imaging studies are performed in the diagnosis of Crohn disease?
What are the goals of treatment in Crohn disease?
How is therapy for Crohn disease typically administered?
What is the role of surgery in the treatment of Crohn disease?
What is the pathogenesis of Crohn disease?
What is the role of granuloma in the pathogenesis of Crohn disease?
What causes bowel obstruction in Crohn disease?
Where are fistulae found in Crohn disease?
Which factors may increase the risk of developing Crohn disease?
What are the roles of the genes IBD1 and NOD2 (CARD15) in the etiology of Crohn disease?
What the role of the gene IL23R in the etiology of Crohn disease?
What are the roles of the genes ITLN1, ATG16L1, IRGM, and PTGER4 in the etiology of Crohn disease?
What are the roles of the genes BSN, MST1, NKX2-3, and PTPN2 in the etiology of Crohn disease?
Which infectious agents may have a role in the etiology of Crohn disease?
What are the roles of interleukins and tumor necrosis factor (TNF) in the etiology of Crohn disease?
What is the prevalence of Crohn disease in the US?
What is the global incidence of Crohn disease?
At what age does the onset of Crohn disease typically occur?
Is Crohn disease more common in males or females?
Does Crohn disease have a racial predilection?
What is the prognosis of Crohn disease?
What is the life expectancy of patients with Crohn disease?
What is the relapse rate for Crohn disease?
Which patients with Crohn disease are at a higher risk of mortality?
How is acute Crohn disease diagnosed and treated?
Are specific genes prognostic factors in Crohn disease?
Where can families and patients obtain educational materials about Crohn disease?
Presentation
What factors determine the clinical presentation of Crohn disease?
What is the focus of medical history in adults and children with suspected Crohn disease?
What is the initial presentation of Crohn disease?
What is the usual presentation of Crohn disease of the small intestine?
What are the signs and symptoms of enterovesical fistulae in Crohn disease?
How often is the terminal ileum involved in Crohn disease in children?
What should be the focus of the physical exam for suspected Crohn disease?
Which abdominal findings suggest Crohn disease?
Which findings of the perineal and rectal exams suggest Crohn disease?
What are the possible extraintestinal manifestations (EIMs) that suggest Crohn disease?
Which skin and oral mucosa findings suggest Crohn disease?
How are growth abnormalities detected in children with suspected Crohn disease?
What is the etiology of major intestinal complications of Crohn disease?
Where does microperforation typically occur in Crohn disease?
What are the signs and symptoms of frank perforation in Crohn disease?
Is colon cancer a possible complication of Crohn disease?
What is the cumulative risk of colon cancer in Crohn disease?
What is the standard of care for colon cancer prevention in Crohn disease?
What is the risk of small bowel cancer in Crohn disease?
When is arthritis likely to occur in adults with Crohn disease?
How often do dermatologic extraintestinal manifestations (EIMs) occur in Crohn disease?
What is the presentation of erythema nodosum in Crohn disease?
What are the dermatologic manifestations of Crohn disease?
What is the most common oral manifestation of Crohn disease?
When do ophthalmologic manifestations of Crohn disease occur?
What are the less common ophthalmologic manifestations of Crohn disease?
What are the urologic extraintestinal manifestations (EIMs) of Crohn disease?
How are gallstones formed in patients with Crohn disease?
What is the most common extraintestinal manifestation (EIM) of Crohn disease?
Which manifestations of liver disease occur in children with Crohn disease?
How common is cholelithiasis (gallstones) in patients with Crohn disease?
What are the symptoms of primary sclerosing cholangitis in patients with Crohn disease?
Does primary sclerosing cholangitis increase the risk of developing Crohn disease?
What are pancreatic or hepatobiliary manifestations of Crohn disease?
What is the etiology of thromboembolic disease in Crohn disease?
What are the risk factors for thromboembolism in Crohn disease?
What are the hematologic and genitourinary manifestations of Crohn disease?
What is the role of malabsorption in Crohn disease?
How is inflammatory bowel disease (IBD) classified?
How is disease activity in adults with Crohn disease assessed?
Which indices are used to assess disease activity in adults with Crohn disease?
DDX
How is Crohn disease differentiated from ulcerative colitis?
What are the differential diagnoses for Crohn Disease?
Workup
How is Crohn disease diagnosed?
What is the role of imaging studies in the diagnosis of Crohn disease?
Which procedures may be useful in the diagnosis of Crohn disease?
What is the role of lab testing in Crohn disease?
What is the role of a CBC count in the diagnosis of Crohn disease?
Which common abnormalities observed on a chemistry panel suggest Crohn disease?
Which acute inflammatory markers may indicate disease activity in Crohn disease?
What is the role of stool sample testing in the evaluation of Crohn disease?
Which serologic tests are useful in differentiating ulcerative colitis from Crohn disease?
Which serologic test results indicate that ulcerative colitis is more likely than Crohn disease?
In addition to ASCAs and p-ANCA, which serologic markers may suggest Crohn disease?
What is the role of abdominal radiography in the diagnosis of Crohn disease?
What is the role of barium contrast studies in the diagnosis of Crohn disease?
What is the role of small bowel follow-through (SBFT) in the diagnosis of Crohn disease?
What is the role of barium enema in the diagnosis of Crohn disease?
What is the role of CT scanning in the diagnosis of Crohn disease?
What is the role of CT enterography in the diagnosis of Crohn disease?
Why is CT scanning the study of choice for the diagnosis of Crohn disease?
What is the role of MRI in the diagnosis of Crohn disease?
Why is MRI the study of choice for evaluation and management of perianal Crohn disease?
Which studies are used for the evaluation of the small bowel in the diagnosis of Crohn disease?
What is the role of ultrasonography in the diagnosis and management of Crohn disease?
Can ultrasonography be used to assess perianal Crohn disease?
What is the role of colonoscopy in the diagnosis and management of Crohn disease?
How effective is an ileocolonoscopy in the assessment of Crohn disease?
What is the role of upper GI endoscopy in the diagnosis of Crohn disease?
What is the role of ERCP in the diagnosis and management of Crohn disease?
What is the role of small bowel enteroscopy or capsule endoscopy in the diagnosis Crohn disease?
What is the role of radionucleotide scanning in the diagnosis and management Crohn disease?
Which test is performed to assess active bowel inflammation in IBD?
What are the common characteristics of inflammation in Crohn disease?
How is upper GI tract Crohn disease typically characterized?
Treatment
What are the general goals of Crohn disease treatment?
How has the development of new therapies affected the treatment of Crohn disease?
Is stem cell transplantation an effective treatment for Crohn disease?
When is resection of malignant bowl strictures indicated in the management of Crohn disease?
When is hospitalization indicated in the management of Crohn disease?
What are the therapy options for mild Crohn disease?
What is the treatment approach for moderate to severe Crohn disease?
In which patient groups is a top-down therapy indicated for the management of Crohn disease?
What are causes of diarrhea in Crohn disease and how is it treated?
How are abdominal cramps reduced in Crohn disease?
How is colon and small bowel inflammation treated in Crohn disease?
What are the indications for corticosteroid therapy in Crohn disease?
What are the possible complications of corticosteroid therapy in Crohn disease?
Which treatments are effective for ileal and cecal Crohn disease?
When are immunosuppressants useful in the treatment of Crohn disease?
What is the role of methotrexate in inducing and maintaining remission in Crohn disease?
When is infliximab indicated in the treatment of Crohn disease?
Is infliximab effective in the treatment of Crohn disease?
What are the possible adverse effects of infliximab in the treatment of Crohn disease?
What are the risk factors for relapse of Crohn disease after successful treatment with infliximab?
Are adalimumab and certolizumab pegol effective in the treatment of Crohn disease?
What is the efficacy of adalimumab in the treatment of Crohn disease?
What is the recommended dosage regimen for adalimumab in the treatment of Crohn disease?
What is the efficacy of certolizumab in the treatment of Crohn disease?
Is natalizumab effective in the treatment of Crohn disease and how is it administered?
Are there restrictions on the use of natalizumab for the treatment of Crohn disease?
When is natalizumab therapy indicated for patients with Crohn disease?
Is vedolizumab effective for the treatment of Crohn disease?
When is ustekinumab indicated for the treatment of Crohn disease?
Is tacrolimus an effective treatment for Crohn disease?
What is the dosing for mycophenolate mofetil in the treatment of Crohn disease?
What is the role of T suis in the treatment of Crohn disease?
Is low-dose oral naltrexone effective for treatment of Crohn disease?
How are fistulae managed in Crohn disease?
How is systemic sepsis managed in Crohn disease?
How are perianal fistulae managed in Crohn disease?
What is the role of nutritional therapy in the treatment of Crohn disease?
Which nutritional therapies are effective in the treatment of Crohn disease?
How is appetite suppression managed in Crohn disease?
Which nutritional supplements are beneficial for patients with Crohn disease?
When is surgery indicated in the management of Crohn disease?
How often is surgical intervention performed in Crohn disease?
What are the ASCRS guidelines for surgical procedures for Crohn disease?
What is the most common complication of Crohn disease and when is surgical intervention required?
How is strictureplasty performed in patients with Crohn disease?
Which complications of Crohn disease may require surgical intervention?
How are abscesses in Crohn disease treated?
How are fistulae treated in Crohn disease?
How are toxic megacolon and massive hemorrhage treated in Crohn disease?
Does segmental bowel resection increase the risk of recurrence of Crohn disease?
What are the possible complications of perianal Crohn disease?
What is the role of a seton in the management of Crohn disease?
What is the efficacy of a laparoscopic surgical approach in Crohn disease?
How does the laparoscopic approach compare to open resection for management of Crohn disease?
What are preoperative steps for resection in patients with Crohn disease?
What is the goal of surgical resection in Crohn disease?
How is laparoscopic resection performed in Crohn disease?
What is the postoperative management of Crohn disease?
What are the most common complications of surgical intervention in Crohn disease?
Which specialists should be involved in the treatment of Crohn disease?
Guidelines
What are the American College of Gastroenterology treatment guidelines for Crohn disease?
What are the guidelines for use of CTE and MRE in patients with small bowel Crohn disease?
Medications
What are the goals of pharmacotherapy in Crohn disease?
How is chronic diarrhea managed in Crohn disease?
When are bile acid sequestrants indicated in the management of Crohn disease?
Which medications may be used to reduce abdominal cramps in Crohn disease?
Which medications may be used to reduce inflammation in Crohn disease?
Which medications have been shown to induce remission in active Crohn disease?
What is the role of mesalamine in the treatment of Crohn disease?
What are the possible complications of steroids in Crohn disease?
How are fistulae between bowel loops managed in Crohn disease?
When is infliximab indicated in the management of Crohn disease?
Which medications in the drug class Corticosteroids are used in the treatment of Crohn Disease?
Which medications in the drug class Immunosuppressants are used in the treatment of Crohn Disease?
Which medications in the drug class Antibiotics are used in the treatment of Crohn Disease?
Which medications in the drug class Antidiarrheals are used in the treatment of Crohn Disease?
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Crohn disease. The colonoscopy image reveals a large ulcer and inflammation of the descending colon in a 12-year-old boy with Crohn disease.
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Crohn disease. This laparoscopic view depicts creeping fat along the mesentery of the terminal ileum.
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Crohn disease. On this laparoscopic photograph, the mesentery of the terminal ileum is being coagulated with a sealing device (LigaSure). Note that the ligation of the mesentery proceeds near the border of the ileum rather than at the base of the mesentery.
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Crohn disease. This postoperative photograph depicts incisions used for laparoscopic ileocolectomy in a 14-year-old male adolescent with obstruction of the terminal ileum. Note the 2-cm incision in the right lower abdomen, through which the specimen was extracted and extracorporeal anastomosis performed. A 12-mm umbilical incision is nicely hidden in the depths of the umbilicus. A 5-mm incision is visible in the left lower abdomen, and another is in the left suprapubic region just above the top of the pants.
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Crohn disease. Colonic granuloma in a patient with Crohn disease is shown (hematoxylin-eosin staining). Image courtesy of Dr E. Ruchelli.
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Crohn disease. Aphthous ulcers. A double-contrast barium enema examination in a patient with Crohn colitis demonstrates numerous aphthous ulcers.
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Crohn disease. This double-contrast barium enema study demonstrates marked ulceration, inflammatory changes, and narrowing of the right colon in a patient with Crohn colitis.
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Crohn disease. Cobblestoning in Crohn disease. This is a spot view of the terminal ileum from a small bowel follow-through study. It demonstrates linear longitudinal and transverse ulcerations that create a cobblestone appearance. Also, note the relatively greater involvement of the mesenteric side of the terminal ileum and the displacement of the involved loop away from the normal small bowel secondary to mesenteric inflammation and fibrofatty proliferation.
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Crohn disease. Crohn disease of terminal ileum. The small bowel follow-through study demonstrates the string sign in the terminal ileum. Also, note the pseudodiverticula of the antimesenteric wall of the terminal ileum, secondary to greater distensibility of this less-involved wall segment.
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Crohn disease. This spot view of the terminal ileum from a small bowel follow-through study in a patient with Crohn disease demonstrates the string sign, consistent with narrowing and stricturing. Also, note a sinus tract originating from the medial wall of the terminal ileum and the involvement of the medial wall of the cecum.
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Crohn disease. Enterocolic fistula in a patient with Crohn disease. The double-contrast barium enema study demonstrates multiple fistulous tracts between the terminal ileum and the right colon adjacent to the ileocecal valve (so-called double-tracking of the ileocecal valve).
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Crohn disease. Active small bowel inflammation in a patient with Crohn disease. This computed tomography scan demonstrates small bowel wall thickening, mesenteric inflammatory stranding, and mesenteric adenopathy.
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Crohn disease. This computed tomography scan from a patient with terminal ileal Crohn disease shows an enteroenteral fistula (arrow) between loops of diseased small intestine.
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Crohn disease. A teenaged patient with Crohn disease underwent contrast-enhanced, upper gastrointestinal computed tomography scanning with small-bowel follow-through. Several loops of small bowel are in the pelvis. Note the loop of distal bowel with thickened wall (solid arrow), which is contrasted with a less-involved loop of bowel in which the intestinal wall is not thickened at all (dotted arrow).
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Crohn disease. This computed tomography scan depicts Crohn disease in the fundus of the stomach.
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Crohn disease. This magnetic resonance image demonstrates an inflamed terminal ileum in 10-year-old girl with Crohn disease.
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Crohn disease. The histologic image shows granuloma in the mucosa of a patient with Crohn disease.