20. Diarrhoea

Question 1

What is the definition of diarrhoea?

Answer 1

Increase in amount of stool passed daily to > 300g- usually accompanied by increased frequency + loosening of the stools

Question 2

What can cause diarrhoea?

Answer 2

Infection
Inflammation: IBD, Diverticular disease
Increased bowel motility: Hyperthyroidism, anxiety, IBS
Malabsorption: Coeliac, pancreatic insufficiency
Obstruction only allowing fluid through
Medications: laxatives, colchicine, digoxin, metformin, thiazide diuretics + some Abx

Question 3

What are the most likely causes of diarrhoea in a young adult?

Going from most to least likely

Answer 3

Infective diarrhoea
IBS
Coeliac disease
Crohn's disease
UC
Medications
Hyperthyroidism

Question 4

What are the most likely causes of diarrhoea and elderly patients?

Answer 4

Neoplastic disease
Diverticular disease
Overflow diarrhoea secondary to constipation
Ischaemic colitis
Microscopic colitis
Bacterial overgrowth
IBD

Question 5

What questions would you ask to characterise the stool?

Answer 5

Is it jelly like/ got mucus in it?
Are they foul smelling + floating?
Are the faeces unusually pale?
Blood?

Question 6

What might mucoid diarrhoea suggest?

Answer 6

Salmonella

Question 7

What does foul smelling/ floating diarrhoea suggest?

Answer 7

Malabsorption

Question 8

What does pale diarrheoa suggest?

Answer 8

Biliary obstruction (lack of bile salts)

Question 9

What would you ask about the patient’s bowel habit if they are presenting with diarrhoea?

Answer 9

Nocturnal diarrhoea?
Do you rush to the toilet?
Tenesmus?
Varbaility in bowel habit
How frequently do you open your bowels?

Question 10

What does urgency in opening bowel suggest?

Answer 10

Infection

IBD

Question 11

What does tenesmus suggest?

Answer 11

space occupying lesion in the rectum- carcinoma

Question 12

What associated symptoms will you ask about in someone with diarrhoea?

Answer 12

FLAWS
vomiting
abdo pain
eye, skin, joint symptoms- IBD

Question 13

What will you ask about in the social history of someone with diarrhoea?

Answer 13

Travel
Close contacts
Changes in diet
Stress

Question 14

What are the blood markers for coeliac disease?

Answer 14

TTG

IgA

Question 15

What signs of IBD should you look for on examination of a patient with diarrhoea?

Answer 15

Clubbing
Iritis
Mouth ulcers (Crohn's)
Erythema nodosum
Anal ulcers/ fistulae (Crohn's)
Abdominal mass in RLQ (Crohn's)

Question 16

What signs of coeliac disease may be found on examination

Answer 16

Clubbing

Dermatitis herpetiformis

Question 17

What signs of malignancy should you look for on examination of a patient with diarrhoea?

Answer 17

Virchows lymphadenopathy

Abdominal masses

Question 18

What can predispose you to C. difficile?

Answer 18

Antibiotics

Question 19

Why should patients with UC be offered regular colonoscopies?

Answer 19

They have an increased risk of colon cancer

Question 20

What is the most likely infective organism in an outbreak of vomiting and diarrhoea in an old persons nursing home?

Answer 20

Norovirus

Question 21

What is the most likely infective organism in an outbreak of bloody diarrhoea at a primary school?

Answer 21

Shigella

E. Coli

Question 22

What is the most likely infective organism in a student with watery diarrhoea a few days after a BBQ?

Answer 22

Campylobacter jejuni

Question 23

What is the most likely infective organism in a group of people with sudden onset diarrhoea a few hours after a party?

Answer 23

Staphylococcus aureus

Bacillis cereus

Question 24

What causes the rapid or slow onset of diarrhoea in infection?

Answer 24

Rapid: bacteria have excreted active toxins
Slow: Bacterial growth in the bowel

Question 25

What is the most likely infective organism in an elderly patient in hospital receiving antibiotics for pneumonia?

Answer 25

Clostridium difficile

Question 26

What is the most likely infective organism in a young woman who has just returned from Ghana and has right iliac fossa pain?

Answer 26

Yersinia enterocolitica

Question 27

What are the 3 possible outcomes of a fluid challenge?

Answer 27

No response: hasn’t received enough fluid or weren’t hypovolaemic to begin with
Transient response: haven’t given enough fluid or is losing them rapidly e.g. haemorrhage
Sustained response: restoration to normal fluid balance