Diarrhoea

Question 1

What is the BSG definition of diarrhoea?

Answer 1

‘Diarrhoea is the abnormal passage of lloose or liquid stools more than three times daily and/or a volume of stool greater than 200 g/day’

Question 2

What is the difference between acute and chronic diarrhoea?

Answer 2

•Acute diarrhoea = less than 4 weeks

Mostly: infectious and self limiting

?investigate after 1 week

•Chronic diarrhoea = more than 4 weeks

Chronic pathology

Always investigate

Question 3

What are the viral, bacterial and parasitic causes of acute diarrhoea?

Answer 3

Viral:

• Rotavirus
• Norovirus
• Enteric adenovirus

Bacterial:

• Salmonella
• Shigella
• Campylobacter
• Staph.aureus

Parasitic:

•Cryptosporidium parvum

Question 4

Which parastitic causes can cause chronic diarrhoea?

Answer 4

Can be chronic -

• Giardia lamblia
• Entamoeba histolytica

Question 5

Name the colonic and small bowel causes of chronic diarrhoea?

Answer 5

Colonic:

• Ulcerative & Crohn’s colitis
• Microscopic colitis
• Colorectal cancer

Small bowel:

• Coeliac disease
• Crohn’s disease
• Bile salt malabsorption
• Lactose intolerance
• Small bowel bacterial overgrowth

Question 6

Name the pancreatic and endocrine causes of chronic diarrhoea

Answer 6

Pancreatic:

• Chronic pancreatitis
• Pancreatic cancer
• Cystic fibrosis

Endocrine:

• Hyperthyroidism
• Diabetes
• Addison’s disease
• Hormone secreting tumours (e.g. Carcinoid, VIPoma)

Question 7

What are the other causes of chronic diarrhoea?

Answer 7

• Drugs
• Alcohol
• Factitious (pretending to be ill)

Question 8

What are the different mechanisms of diarrhoea?

Answer 8

• Osmotic e.g. lactose intolerance
• Steatorrhoea
• Secretory e.g.Cholera, E. Coli, gut hormones
• Inflammatory e.g. UC, Crohn’s, infections
• Neoplastic
• Ischaemic
• Post irradiation

Question 9

What are the investigations for chronic diarrhoea?

Answer 9

•Stool tests: Microscopy & culture

Faecal elastase

Faecal calprotectin

• Blood tests: Many (e.g.FBC, CRP, TTG, TFT’s, B12 etc)
• Imaging: Colonoscopy,

CT, video capsule, MRI small bowel

(Ba enema, small bowel enema)

Question 10

What does this show?

Answer 10

Endoscopic appearance of Ulcerative colitis

Question 11

What does this show?

Answer 11

Endoscopic appearance of Crohn’s disease

Question 12

What is ulcerative collitis?

Answer 12

…continuous mucosal inflammation of the colon without granulomas on biopsy, affecting the rectum and a variable extent of the colon in continuity and characterised by a relapsing and remitting course.

Question 13

What is crohns disease?

Answer 13

…discontinuous and often granulomatous transmural inflammation affecting any area of the gastrointestinal tract.

Question 14

What is the distribution of CD throughout the GI tract?

Answer 14

Distribution: Terminal ileum – 30%

Colonic – 30%

Ileo-colic – 30%

Other

Question 15

Which is which IBD?

Answer 15

Question 16

What are the symptoms of UC?

Answer 16

• Bloody diarrhoea, rectal bleeding, mucus, faecal urgency, abdo pain, nocturnal defecation
• Extraintestinal manifestations (arthritis, uveitis, erythema nodosum, pyoderma gangrenosum)
• Primary sclerosing cholangitis (3-7% patients with UC)

Question 17

What is the onset of UC?

Answer 17

•Often insidious onset (not clear cut)

Question 18

What are the investigations for UC?

Answer 18

ØStool cultures + CDT

ØFaecal calprotectin

ØCRP

ØFBC

ØAlbumin

ØFlexible sigmoidoscopy/colonoscopy

Question 19

Who is most likely to get UC?

Answer 19

• Any age (peak teens/early adulthood)
• M:F 1:1
• Positive effect of smoking! (ex-smokers 70% increased risk of UC)
• Appendicectomy protective (before age 20)
• 10-15 fold risk in 1st degree relatives (2% lifetime risk)

Question 20

Does UC or CD have a relapsing/remitting course?

Answer 20

Both

Question 21

Whats the diagnosis?

Answer 21

Ulcerative Colitis

Question 22

What is the treatment for severe UC?

Answer 22

• Admit
• Hydrocortisone 100mg iv qds
• Heparin s.c.
• Stool chart
• AXR

Daily CRP

Question 23

What should be avoided in severe UC?

Answer 23

•AVOID: NSAID’s, opiates, anti-motility agents

Question 24

What percentage of severe UC admissions -

• Response to steroids
• Colectomy
• Mortality

Answer 24

• Response to steroids 67%
• Colectomy 29%
• Mortality 1%

Question 25

What is the treatment for severe UC in patients who fail to respond to steroids?

Answer 25

• Infliximab
• (Cyclosporin)
• Colectomy

Question 26

What is the treatment for mild-moderate UC?

Answer 26

•Mesalazine (5 ASA)

–Oral

–Topical: suppository, enema

• Prednisolone – reducing course
• Azathioprine
• Biologics:

–Anti-TNF agents e.g. Infliximab, adalimumab

–a4b7 integrin blocker: Vedolizumab

–Tyrosine kinase inhibitor: Tofacitinib (oral agent)

•(Surgery)

Question 27

Who is morest likely to develop Crohns disease?

Answer 27

• Any age (peak teens/early adulthood)
• M:F 1:1
• Smoking
• Previous appendicectomy
• Family history
• Infectious gastroenteritis (increase risk in following year)

Question 28

What are the symptoms of Crohns Disease?

Answer 28

–Chronic diarrhoea most common

–IBS type symptoms

–Abdo pain (in 70%)

–Weight loss (in 60%)

–Anaemia

–Growth failure in children

– Blood +/- mucus in stools (40-50% of Crohn’s colitis)

–Perianal disease

–Extraintestinal manifestations (e.g. arthritis, uveitis, erythema nodosum

Question 29

What are the 4 subtypes of Crohns disease?

Answer 29

• Inflammatory disease
• Stricturing disease: infammatory/fibrotic
• Fistulating disease
• Perianal disease

Question 30

Whats the diagnosis?

Answer 30

CD

Question 31

Whats the diagnosis?

Answer 31

CD

Question 32

What is the treatment for CD?

Answer 32

• (5 ASA preparations)
• Prednisolone/Budesonide (corticosteroids)
• Azathioprine/6-Mercaptopurine (purine analogue)
• Methotrexate (inhibits folic acid metabolism)
• Nutritional therapy (elemental diet)
• Antibiotics
• Biologics, e.g. Infliximab, adalimumab (anti-TNF), Vedolizumab (a4b7 integrin blocker), Ustekinumab (IL-12 &IL-23 inhibitor)
• Surgery

Question 33

How can you tell apart CD and UC?

Answer 33