Crohn's and Ulcerative colitis

Question 1

Crohns - definition

Answer 1

Chronic inflammatory disease characterised by transmural granulomatous inflammation.

It can affect any part of the GI tract from the mouth to the anus but favours the terminal ileum and proximal colon.

There are unaffected sections of bowel between areas of active disease – skip lesions.

Question 2

Crohns - causes

Answer 2

Unknown but mutations of the NOD2/CARD15 genes are thought to increase risk of disease. Smoking is known to increase the risk by 3-4 times (unlike UC) and NSAIDs may exacerbate disease.

Question 3

Crohns - symptoms

Answer 3

Diarrhoea, abdominal pain and weight loss are common – presents as failure to thrive in children. When there is active disease patients may also have fever, malaise and anorexia.

Question 4

Crohns - signs

Answer 4

Aphthous ulceration, abdominal tenderness or right iliac fossa pain, perianal abscesses, fistulae or skin tags or anal or rectal strictures.

Extra-intestinal – clubbing, erythema nodosum, pyroderma gangrenosum, eye disease (conjunctivitis, episcleritis or iritis), large joint arthritis, spondyloarthropathy (sacroilitis, ankylosing spondylitis), fatty liver, PSC, cholangiocarcinoma, renal stones or osteomalacia.

Question 5

Crohns - complications

Answer 5

Small bowel obstruction, toxic dilatation (colonic diameter >6cm), abscess formation, fistulae (in 10% e.g. colovesical or colovaginal), perforation, rectal haemorrhage or colonic carcinoma.

Question 6

Crohns - investigations

Answer 6

• Bloods – FBC, ESR, CRP, Us and Es, LFTs and blood cultures. If anaemic measure serum iron, B12 and red cell folate. Low Hb and albumin and raised WCC, CRP and ESR suggest active disease.
• Stool MC+S – to exclude infectious diarrhoea e.g. C difficile, Salmonella or Campylobacter.
• Sigmoidoscopy – if mucosa looks normal do rectal biopsy – 10% have microscopic granulomas.
• Capsule endoscopy – has an important and growing role in assessing the entire GI tract disease.
• Colonoscopy – preferred to barium enema to assess the extent of the disease.
• MRI – can be used to assess pelvic disease and fistulae and look for the presence of strictures.

Question 7

Crohns - management

Answer 7

Severity is more difficult to assess than in UC but if the patient presents with pyrexia, tachycardia, raised WCC, CRP and ESR or low albumin they may require admission.

• Mild attacks – patients are symptomatic but not systemically unwell – give 30mg Prednisalone PO OD for 1 week and 20mg OD for 1 month. If symptoms resolve decrease by 5mg per week.
• Severe attacks – admit for 100mg Hydrocortisone IV QDS and IV rehydration e.g. 1L 0.9% saline, 2L dextrose and 20mmol/L K+ per 24 hours. In addition the patient may require rectal steroids or IV Metronidazole, blood transfusion (if Hb is <10g/dL) or parenteral nutrition.

Question 8

Crohns - additional medical therapy

Answer 8

• Azathioprine – a useful steroid sparing agent if patient is having side effects or is experiencing multiple relapses. Give 2-2.5mg/kg/day PO but will take between 6-10 weeks to take effect.
• Sulfasalazine – efficacy of 5-ASAa in Crohn’s is unproven but may reduce the rate of relapses.
• Methotrexate – 25mg IM per week is recommended for induction of remission and complete withdrawal from steroids in patients with refractory disease – has no significant side effects.

Question 9

Crohns - surgery

Answer 9

50-80% will need at least 1 operation – indications include failure to respond to medical therapy, intestinal obstruction from stricture, perforation, fistulae or abscesses.

The aim of surgery is to defunction (rest) distal diseases e.g. with a temporary ileostomy or limited resection of the worse affected areas however ** short bowel syndrome** is a major complication.

Question 10

Crohns - TNFa inhibitors

Answer 10

e.g. infliximab or adalimumab decrease disease activity by preventing neutrophil accumulation and granuloma formation, activating complement and causing cytotoxicity to CD4+ cells.

The response to treatment may be short lived but it can be repeated after 8 weeks. Side effects – sepsis, deranged LFTs and it should not be given with malignancy.

Question 11

UC - definition

Answer 11

A relapsing and remitting inflammatory disorder of the colonic mucosa. In 50% only the rectum is affected (proctitis), in 30% it extends proximally to involve part of the colon (left sided colitis) and in the remaining 20% the entire colon is affected (pancolitis). It never passes the ileocaecal valve.

Question 12

UC - pathology

Answer 12

Hyperaemic or haemorrhagic granular colonic mucosa with pseudopolyps formed by inflammation. Punctate ulcers may extend deep into the lamina propria but is not transmural.

Question 13

UC - epidemiology

Answer 13

Incidence is 10-20 per 100,000 per year and men and women are affected equally. Most present at 15-30 years and UC is 3 times more common in non-smokers (opposite to Crohn’s).

Question 13

UC - symptoms

Answer 13

Gradual onset diarrhoea (± blood/mucus) and abdominal cramps. Urgency and tenesmus also occur with rectal disease.

Systemic features include fever, malaise, anorexia and weight loss.

Question 14

UC - signs

Answer 14

Can be none or in acute, severe UC there may be tachycardia and a tender, distended abdomen.

Extra-Intestinal signs – conjunctivitis, episcleritis, iritis, apthous oral ulcers, clubbing, erythema nodosum, pyoderma gangrenosum, arthritis, sacroiliitis, ankylosing spondylitis, fatty liver, primary sclerosing cholangitis, cholangiocarcinoma, nutritional deficitis or amyloidosis.

Question 15

UC - investigations

Answer 15

• Bloods – FBC, CRP, ESR, Us and Es, LFTs and blood cultures.
• Stool microscopy, culture and sensitivity – to exclude infections e.g. C. diff or Salmonella.
• Abdominal x-ray – show no faecal shadows, mucosal thickening and islands or colonic dilation.
• Sigmoidoscopy – will show inflamed mucosa and rectal biopsy will show inflammatory infiltrate, goblet cell depletion, glandular distortion, mucosal ulceration or crypt abscesses.
• Colonscopy – can be used to assess the extent of the disease and can also take a biopsy.

Question 16

UC - Truelove-Witts criteria

Answer 16

Used to assess the severity of ulcerative colitis:
criteria are mild, moderate or severe.

• Motions per day - <4, 4-6 or >6.
• Rectal bleeding - small, medium or large
• 6am temperature - apyrexial, 37.1-37.8 °C or >37.8 °C.
• Pulse rate – bpm <70, 70-90 or >90.
• Haemoglobin - >11 g/dL 10.5-11 g/dL or <10.5 g/dL.
• ESR - <30 mm/h or >30 mm/h.

Question 17

UC - complications

Answer 17

Perforation and bleeding, toxic dilatation of the colon, venous thrombosis or colonic cancer – with pancolitis risk is 15% within 20 years so 2-4 yearly surveillance colonscopy may be used.

Question 18

UC - inducing remission

Answer 18

Move up to the next level if there is no improvement in 2 weeks:

• Mild UC – give 20-40mg Prednisolone PO OD and 1g Mesalazine PO TDS. For mild distal disease could use steroid (hydrocortisone or prednisolone) retention enemas BD.
• Moderate UC – give 40mg Prednisolone PO OD and a 5-ASA and steroid enema BD.
• Severe UC – admit the patient, keep them nil by mouth and give IV rehydration, 100mg hydrocortisone IV QDS and 100mg/100mL in 0.9% saline hydrocortisone PR BD.

Question 19

UC - topical therapy

Answer 19

Proctitis may respond well to prednisolone or mesalazine suppositories. Procto-sigmoiditis is better relieved by foams with a disposable applicator to aid delivery.

Question 20

UC - surgery

Answer 20

Required by 20% and indications include perforation, haemorrhage, toxic dilation or failure to respond to medical therapy.

Possible procedures include proctocolectomy and terminal ileostomy (may be possible to retain iliocaecal valve to reduce fluid loss) or colectomy with ileo-anal pouch.

Surgical mortality is 2-7% but rises to 50% if there has been a perforation.

Question 21

UC - novel therapy

Answer 21

A short course of 2mg/kg Ciclosporin IV per day may help achieve remission in patients with steroid refractory UC (it is very nephrotoxic so cannot be used long term).

Question 22

UC - maintaining remission

Answer 22

All 5-ASAs e.g. 500mg Sulfasalazine PO QDS reduce relapse rate from 80% to 20% at 1 year. Azathioprine can be used where there are steroid side effects.

Question 23

IBS - definition

Answer 23

A mixed group of intestinal symptoms for which no organic cause can be found. Most cases are probably due to disorders of intestinal motility or enhanced visceral perception (the brain-gut axis). Prevalence is between 10-20%, the female : male ratio is 2:1 and the average age of onset is <40 years.

Question 24

IBS - diagnosis

Answer 24

There must be abdominal pain relieved by defecation or associated with altered stool form or bowel frequency and >2 of the following – urgency, incomplete evacuation, abdominal bloating or distension, mucous PR or worsening of symptoms after food.

Question 25

IBS - other symptoms and signs

Answer 25

• Symptoms – nausea, bladder symptoms or backache. Symptoms are usually chronic and can be exacerbated by stress, menstruation or gastroenteritis (post-infection IBS).
• Signs – examination often normal but generalised abdo tenderness is common. Insufflation of the bowel during sigmoidoscopy usually reproduces symptoms (but not usually needed).

Question 26

IBS - features suggesting other diagnosis

Answer 26

Age >40 years, history <6 months duration, anorexia, weight loss, waking at night with pain or diarrhoea, abnormal CRP/ESR, haemoglobin or coeliac serology.

Question 27

IBS - investigations

Answer 27

Important to make a positive diagnosis but also to exclude alternative diagnoses’:

• If classic history – FBC, CRP, ESR, LFTs and coeliac serology will be sufficient investigation.
• If >60 years or red flag symptoms – pyrexia, blood PR or weight loss do an urgent colonoscopy.

Question 28

IBS - referral

Answer 28

Should be made if diagnosis unsure, changing symptoms in known IBS, to surgeon if rectal mucosal prolapse, to dietician if food intolerance, to counsellor if stress or depression induced IBS, to gynaecologist if cyclical pain, dyspareunia or dysmenorrhoea (endometriosis often mimics IBS) or to a pain clinic if there is overlapping chronic pain syndromes.

Question 29

IBS - management

Answer 29

• Food intolerance – may be to bran, whole grains or fructose – try exclusion diets, drink 8 cups of fluid per day (avoid tea, coffee and fizzy drinks) and suggest a once daily probiotic drink.
• Constipation – increase fibre intake or try fybogel (non-fermenting so preferred to lactulose).
• Diarrhoea – avoid sorbitol (artificial sweetener) and try a bulking agent ± 2mg loperamide after each loose stool (max 16mg /day) but can cause colic, nausea, dizziness or constipation.
• Colic or bloating – antispasmotics e.g. 135mg mebeverine TDS (available over the counter).
• Dyspepsia – may respond to metoclopramide or antacids e.g. 20mg omeprazole BD.

Question 30

IBS - psychological management

Answer 30

Emphasize positive aspects e.g. in 50% symptoms improve or go away within a year and <5% worsen. CBT or gut-focus hypnotherapy may also have a role in tx.