Diarrhoea

Question 1

Acute diarrhoea

Answer 1

Abnormal passage of loose stools 3+ times a day.

Volume of stool 200g/day

Acute- lasts less than 4 weeks

Cause: Most likely infectious

Most likely to resolve, investigate after a week

Question 2

Chronic diarrhoea

Answer 2

Diarrhoea lasting more than 4 weeks.

Cause: chronic pathology like an inflammatory disease

Question 3

Viral cause of diarrhoea [3]

Answer 3

Most likely to cause acute diarrhoea:

• Rotavirus
• Norovirus
• Enteric adenovirus

Question 4

Bacterial cause of diarrhoea [4]

Answer 4

Salmonella

Shigella

Campylobacter

S.aureus

Question 5

Parasitic cause of diarrhoea [3]

Answer 5

Cryptosporidium parvum

Giardia lamblia

Entamoeba histolytica

Question 6

Colonic causes of chronic diarrhoea

Answer 6

Ulcerative and Crohn’s colitis.

Microscopic colitis.

Colorectal cancer

Question 7

Small bowel cause of chronic diarrhoea

Answer 7

Coeliac disease

Crohn’s disease

Bile salt malabsorption

Lactose intolerance

Small bowel bacterial overgrowth- small bowel is supposed to be sterile

Question 8

Pancreatic cause of chronic diarrhoea

Answer 8

Chronic pancreatitis

Pancreatic cancer

Cystic fibrosis

Question 9

Endocrine causes of chronic diarrhoea

Answer 9

Hyperthyroidism

Diabetes

Addison’s disease

Hormone secreting tumors.

Question 10

Mechanisms diarrhoea [7]

Answer 10

Osmotic: water is drawn from the blood. e.g lactose intolerance

Steatorrhoea: Fat malabsorption

Secretory: secretion of toxins/ hormone dysfunction.

• E.coli
• Cholera

Inflammatory: Crohn’s, ulcerative colitis

Neoplastic

Ischaemic

Post irradiation

Question 11

Investigations for diarrhoea

Answer 11

Stool tests

Blood test

Colonoscopy
CT
Video capsule
MRI small bowel

Question 12

Examination for diarrhoea

Answer 12

Tenderness when palpating abdomen?

Anal examination: visual inspection
- amount of stool in anus

Stool examination

Rigid sigmoidoscopy: inspects rectal mucosa to help exclude UC

Question 13

Ulcerative colitis

Answer 13

Continuous mucosal inflammation of the colon.

• No granulomas on biopsy
• Affects the rectum

Question 14

Crohn’s disease

Answer 14

Discontinuous inflammation affecting any area of the GI tract.

• Often transmural and contains granulomas

Distribution, mainly:
Terminal ileum
Colon
Ileo-colic

Question 15

Endoscopic appearance of Crohn’s disease

Answer 15

• Patchy erythema

- Cobblestone mucosa

Question 16

Stool test investigation

Answer 16

Used to diagnose cause of diarrhoea.

• Culture of microbes: bacteria?
• Faecal elastase:

Question 17

Symptoms of ulcerative colitis

[5]

Answer 17

Blood diarrhoea

Rectal bleeding

Mucus in faeces

Abdominal pain

Nocturnal defecation

Question 18

Extraintestinal manifestations of ulcerative colitis

Answer 18

Arthritis

Uveitis

Erythema nodosum

Pyoderma gangrenosum

Primary sclerosing cholangitis

Question 19

Treatment of severe ulcerative colitis

Answer 19

Hospital admission

Hydrocortisone

Heparin

Daily c-reactive protein test

Question 20

Drug to AVOID when treating sever UC

Answer 20

NSAIDs

Opiates

Antimotility agents

Question 21

Treatment for patients with severe UC who fail to respond to steroids

Answer 21

Infliximab

Cyclosporin

Colectomy

Question 22

Treatment for mild-moderate UC

Answer 22

Mesalazine

Prednisolone

Azathioprine

Anti-TNF agents

Surgery possibly

Question 23

Epidemiology of Crohn’s disease

Answer 23

Mainly affects teens/young adults

Affects both sexes equally

Presents in a relapsing/remitting course

Associated with smoking

Previous appendectomy

Risk increased with infectious gastroenteritis

Question 24

Crohn’s disease symptoms

Answer 24

Chronic diarrhoea

Abdominal pain and weight loss are very common

Anaemia

Growth failure in children

Question 25

Crohn’s disease pathology

Answer 25

Any part of the GI tract- discontinuous fashion

Transmural inflammation

Deep ulcers

Fissures

Fistulas

Abscesses

Perianal

Question 26

Similarities between UC and Crohn’s disease

Answer 26

Both affect any age and peak ages 20-40.

Both Inflammatory bowel diseases

Both show diarrhoea

Both have extraintestinal manifestation

Question 27

Differences between UC and Crohn’s disease [4]

Answer 27

UC: affects only the colon, continuously.
Crohn’s: affects any part of the GI, discontinuously.

UC affects more people in the population

UC: mucosal inflammation
Crohn’s: transmural inflammation

Crohn’s presents with deep ulcers and fissures, fistulas and abscesses- UC doesn’t really.