Inflammatory bowel disease: Crohn's disease

Question 1

What is Crohn’s disease?

Answer 1

Crohn’s disease is a form of inflammatory bowel disease that commonly affects the terminal ileum and colon but may occur anywhere from the mouth to anus.

Question 2

What is the cause of Crohn’s disease?

Answer 2

The cause is unknown, but there is a strong genetic susceptibility.

Question 3

What layers of the gastrointestinal tract are affected by Crohn’s disease?

Answer 3

Inflammation occurs in all layers, down to the serosa.

Question 4

What complications are patients with Crohn’s disease prone to?

Answer 4

Patients are prone to strictures, fistulas, and adhesions.

Question 5

What percentage of Crohn’s disease patients have small bowel involvement?

Answer 5

80% of patients have small bowel involvement, usually in the ileum.

Question 6

What are the common presentations of Crohn’s disease?

Answer 6

Common presentations include weight loss, lethargy, diarrhea, abdominal pain, and perianal disease.

Question 7

What is the most prominent symptom of Crohn’s disease in adults?

Answer 7

Diarrhea is the most prominent symptom in adults.

Question 8

What is the most prominent symptom of Crohn’s disease in children?

Answer 8

Abdominal pain is the most prominent symptom in children.

Question 9

What investigations are commonly performed for Crohn’s disease?

Answer 9

Investigations include raised inflammatory markers, increased faecal calprotectin, anemia, and low vitamin B12 and vitamin D.

Question 10

What are common extra-intestinal features of Crohn’s disease?

Answer 10

Common features include arthritis, erythema nodosum, episcleritis, and osteoporosis.

Question 11

What type of arthritis is most common in Crohn’s disease?

Answer 11

Pauciarticular, asymmetric arthritis is related to disease activity.

Question 12

What extra-intestinal feature is more common in Crohn’s disease than in ulcerative colitis?

Answer 12

Episcleritis is more common in Crohn’s disease.

Question 13

What extra-intestinal features are unrelated to disease activity?

Answer 13

Unrelated features include polyarticular, symmetric arthritis, uveitis, pyoderma gangrenosum, clubbing, and primary sclerosing cholangitis.

Question 14

Which extra-intestinal feature is much more common in ulcerative colitis?

Answer 14

Primary sclerosing cholangitis is much more common in ulcerative colitis.

Question 15

Which extra-intestinal feature is more common in ulcerative colitis than in Crohn’s disease?

Answer 15

Uveitis is more common in ulcerative colitis.

Question 16

What is Crohn’s disease?

Answer 16

Crohn’s disease is a form of inflammatory bowel disease that commonly affects the terminal ileum and colon but may be seen anywhere from the mouth to anus.

Question 17

What blood test correlates well with Crohn’s disease activity?

Answer 17

C-reactive protein correlates well with disease activity.

Question 18

What is the investigation of choice for Crohn’s disease?

Answer 18

Colonoscopy is the investigation of choice.

Features suggestive of Crohn’s include deep ulcers and skip lesions.

Question 19

What histological features are associated with Crohn’s disease?

Answer 19

Inflammation in all layers from mucosa to serosa, goblet cells, and granulomas.

Question 20

What is the role of small bowel enema in Crohn’s disease?

Answer 20

It has high sensitivity and specificity for examination of the terminal ileum.

Strictures may present as ‘Kantor’s string sign’, proximal bowel dilation, ‘rose thorn’ ulcers, and fistulae.

Question 21

What is Crohn’s disease?

Answer 21

Crohn’s disease is a form of inflammatory bowel disease that commonly affects the terminal ileum and colon but may be seen anywhere from the mouth to anus.

Question 22

What guidelines were published for the management of Crohn’s disease?

Answer 22

NICE published guidelines on the management of Crohn’s disease in 2012.

Question 23

What general advice should be given to patients with Crohn’s disease?

Answer 23

Patients should be strongly advised to stop smoking. Some studies suggest an increased risk of relapse secondary to NSAIDs and the combined oral contraceptive pill, but the evidence is patchy.

Question 24

What is the first-line treatment to induce remission in Crohn’s disease?

Answer 24

Glucocorticoids (oral, topical, or intravenous) are generally used to induce remission.

Question 25

What alternative medication may be used in a subgroup of patients to induce remission?

Answer 25

Budesonide is an alternative in a subgroup of patients.

Question 26

What dietary approach may be used to induce remission?

Answer 26

Enteral feeding with an elemental diet may be used in addition to or instead of other measures to induce remission, particularly if there is concern regarding the side-effects of steroids.

Question 27

What second-line medication is used to induce remission?

Answer 27

5-ASA drugs (e.g. mesalazine) are used second-line to glucocorticoids but are not as effective.

Question 28

What medications may be used as add-on therapy to induce remission?

Answer 28

Azathioprine or mercaptopurine may be used as an add-on medication to induce remission but are not used as monotherapy. Methotrexate is an alternative to azathioprine.

Question 29

What is the role of infliximab in Crohn's disease?

Answer 29

Infliximab is useful in refractory disease and fistulating Crohn's. Patients typically continue on azathioprine or methotrexate.

Question 30

What is often used for isolated peri-anal disease?

Answer 30

Metronidazole is often used for isolated peri-anal disease.

Question 31

What is the priority for maintaining remission in Crohn's disease?

Answer 31

Stopping smoking is a priority.

Question 32

What is the first-line medication used to maintain remission?

Answer 32

Azathioprine or mercaptopurine is used first-line to maintain remission.

Question 33

What should be assessed before starting azathioprine or mercaptopurine?

Answer 33

+TPMT activity should be assessed before starting.

Question 34

What is used second-line to maintain remission?

Answer 34

Methotrexate is used second-line.

Question 35

What percentage of patients with Crohn's disease will eventually have surgery?

Answer 35

Around 80% of patients with Crohn's disease will eventually have surgery.

Question 36

What surgical procedure is performed for stricturing terminal ileal disease?

Answer 36

Ileocaecal resection.

Question 37

What is the investigation of choice for suspected perianal fistulae?

Answer 37

MRI is the investigation of choice for suspected perianal fistulae.

Question 38

What is a draining seton used for?

Answer 38

A draining seton is used for complex fistulae to keep the fistula open.

Question 39

What is required for a perianal abscess?

Answer 39

Incision and drainage combined with antibiotic therapy.

Question 40

What are some complications of Crohn's disease?

Answer 40

Patients are at risk of small bowel cancer, colorectal cancer, and osteoporosis.

Question 41

What is the standard incidence ratio for small bowel cancer in Crohn's disease?

Answer 41

Standard incidence ratio = 40.

Question 42

What is the standard incidence ratio for colorectal cancer in Crohn's disease?

Answer 42

Standard incidence ratio = 2.

Question 43

What are the two main types of inflammatory bowel disease?

Answer 43

Crohn's disease and ulcerative colitis.

Question 44

What are some common symptoms of Crohn's disease?

Answer 44

Diarrhoea usually non-bloody, weight loss more prominent, upper gastrointestinal symptoms, mouth ulcers, perianal disease, and abdominal mass palpable in the right iliac fossa.

Question 45

What are some common symptoms of ulcerative colitis?

Answer 45

Bloody diarrhoea more common, abdominal pain in the left lower quadrant, and tenesmus.

Question 46

What extra-intestinal manifestation is more common in Crohn's disease?

Answer 46

Gallstones are more common due to reduced bile acid reabsorption.

Question 47

What complications are associated with Crohn's disease?

Answer 47

Obstruction, fistula, and colorectal cancer.

Question 48

What complications are associated with ulcerative colitis?

Answer 48

Higher risk of colorectal cancer compared to Crohn's disease.

Question 49

Where can lesions be seen in Crohn's disease?

Answer 49

Lesions may be seen anywhere from the mouth to anus, with skip lesions present.

Question 50

Where does inflammation start in ulcerative colitis?

Answer 50

Inflammation always starts at the rectum and never spreads beyond the ileocaecal valve.

Question 51

What histological features are seen in Crohn's disease?

Answer 51

Inflammation in all layers from mucosa to serosa, increased goblet cells, granulomas.

Question 52

What histological features are seen in ulcerative colitis?

Answer 52

No inflammation beyond submucosa (unless fulminant disease), depletion of goblet cells and mucin from gland epithelium, granulomas are infrequent.

Question 53

What endoscopic findings are characteristic of Crohn's disease?

Answer 53

Deep ulcers, skip lesions, and 'cobble-stone' appearance.

Question 54

What endoscopic findings are characteristic of ulcerative colitis?

Answer 54

Widespread ulceration with preservation of adjacent mucosa, which has the appearance of polyps ('pseudopolyps').

Question 55

What radiological findings are associated with Crohn's disease?

Answer 55

Small bowel enema showing strictures, proximal bowel dilation, 'rose thorn' ulcers, and fistulae.

Question 56

What radiological findings are associated with ulcerative colitis?

Answer 56

Barium enema showing loss of haustrations, superficial ulceration, and 'pseudopolyps'.

Question 57

Which extra-intestinal manifestation is much more common in ulcerative colitis than in Crohn's disease?

Answer 57

Primary sclerosing cholangitis (82%).