CBL 12 - A patient with diarrhoea

Question 1

Q1. What is the differential diagnosis?

Answer 1

UC
Crohns
Diverticulosis
Coeliac disease
Ischaemic colitis
Bowel cancer
Infective colitis
IBS
Haemorrhoids
Fistula
Giardia infection
Pancreatic enzyme insufficiency

Question 2

Haemorrhoids vs fistula presentation

Question 3

Blood in stool - how do you differentiate?

look up more

Answer 3

Mixed with stool?
Frank red bood

Question 4

What does mucus in the stool indication? [1]

Answer 4

Inflammation (of the stool)

Question 5

On examination, he looked a little pale, pulse rate 98 bpm and BP 110/70 mmHg. Abdomen is distended with slight tenderness throughout.

Q2. What were the abnormal findings you identified on general physical examination and abdominal examination?

Answer 5

• little pale
• BP 110/70 mmHg
• Abdomen is distended with slight tenderness throughout.

Question 6

Q3. What investigations should be requested? [+]

Answer 6

FBC
U&E
LFTs
Calcium, B12, RBC folate, ferritin levels
TFTS
ESR
CRP
antiTTG IgA levels
Faecal calprotectin
Stool culture - MCS (esp. C-diff)
Faecal elastase (pancreatic insufficiency)

Question 7

How do you specifically investigate stool cultures? [2]

Answer 7

Send three cultures, two days apart

Question 8

What the typical infective organisms that cause bloody diarrhoea? [5]

Answer 8

• Non-typhoidal salmonellosis (e.g. S. typhimurium, S. enteritidis)
• Campylobacter spp. (e.g. C. jejuni, C. coli)
• Shigella spp. (S. dysenteriae, S. flexneri, S. boydii, S. sonnei)
• Yersinia enterocolitica
• Enterohaemorrhagic Escherichia coli (EHEC)

Question 9

[] is the most common cause of gastroenteritis in children.

Answer 9

Rotavirus is the most common cause of gastroenteritis in children.

Question 10

[] is the most commonly implicated bacterial cause of gastroenteritis.

Answer 10

Campylobacter is the most commonly implicated bacterial cause of gastroenteritis.

Question 11

[] commonly causes a vomiting illness after reheating starchy food (e.g. rice).

Answer 11

Bacillus cereus commonly causes a vomiting illness after reheating starchy food (e.g. rice).

Question 12

[] is a classic cause of dysentery in young children.

Answer 12

Shigella is a classic cause of dysentery in young children.

Question 13

[] is commonly implicated in Travellers’ diarrhoea.

Answer 13

Giardia lamblia is commonly implicated in Travellers’ diarrhoea.

Question 14

A sigmoidoscopy is performed in clinic and reveals a friable, spontaneously haemorrhagic granular mucosa to the limit of view and a biopsy was taken. He is admitted to hospital from the clinic.

Q4. What is the differential diagnosis based on above?

Answer 14

UC [?]

Early in the disease, the mucous membrane is erythematous, finely granular, and friable, with loss of the normal vascular pattern and often with scattered hemorrhagic areas.

Question 15

Q5. List the abnormal findings on blood tests, and what do these abnormal results indicate regarding the underlying disease?

Answer 15

Low HB
- Anaemia

Raised white blood count - inflammation

Raised Platelets - active bleeding
Low Potassium - from diarrhoea

CRP - inflammation

Indicates active inflamation occurring.

Question 16

What imaging do you perform for UC? [2]

Answer 16

1. flexible sigmoidoscopy
2. full colonoscopy

A colonoscopy must be avoided in acute severe disease due to the increased risk of bowel perforation

Question 17

What are the macroscopic [5] and microscopic [2] changes seen in UC?

Answer 17

Macroscopic findings:
* Continuous, uniformly inflamed mucosa
* Erythematous, friable mucosa
* Abnormal vascular pattern
* Ulceration
* Inflammatory polyps (‘pseudopolyps’)

Microscopic findings (biopsy):
* Crypt abscesses
* Decreased goblet cell abundance

Question 18

Describe Truelove & Witt criteria of mild, moderate and severe to grade UC, based off:

• Bowel movements per day
• Blood in stool
• Pyrexia
• Pulse (>90BPM)
• Anaemia
• ESR

Answer 18

Question 19

Q6. Why was this patient admitted from the clinic?

Answer 19

He’s presenting with severe UC, which requires admission

Question 20

Which autoimmune antibody is associated with UC? [1]

Answer 20

pANCA (if PSC is suspected)

Question 21

Q7. Which is the next most appropriate investigation for this man while in ED and why?

Answer 21

Additional imaging modalities such as plain abdominal X-ray (AXR) and computed tomography (CT) may be important for the exclusion of UC complications in an acute presentation (e.g. toxic megacolon, bowel perforation).

Question 22

Q8. What does the XR abdomen show?

Answer 22

Toxic megacolon

This patient’s colon is very dilated and there are extensive ‘mucosal islands’ indicating bowel wall inflammation.

Question 23

What size toxic megacolon should you be concerned about? [1]

Answer 23

Diameter > 6cm

Question 24

Stool cultures return as negative. The gastroenterology team comes to review him.
Q9. Mr. R had given up smoking recently. Is that relevant to his clinical presentation?

Answer 24

Yes - smoking is protective in UC

? It has been reported that nicotine increases the thickness of colonic mucus, thus enhancing the protection of the intestinal mucosa [14], but this remains to be confirmed.

It is possible that nicotine may increase the production of this mucus

Question 25

What is the medical management for UC? [+]

Answer 25

Aminosalicylates (5-ASAs):
- (first line)
- mesalamine, sulfasalazine, and balsalazid

Corticosteroids:
- Prednisone, hydrocortisone, and budesonide

Biologic therapies:
- Anti-tumor necrosis factor (anti-TNF) agents: infliximab, adalimumab, golimumab
- anti-integrin agents: vedolizumab
- anti-interleukin-12/23 agents: ustekinumab
- janus kinase (JAK) inhibitors: tofacitinib

Question 26

What biopsy findings would you see in UC? [3]

Answer 26

Goblet cell depletion
No inflammation beyond submucosa
Neutrophils migrate to form cypry abcesses
Granulomas infrequent

Question 27

Q10. What management will take place in the hospital?

Answer 27

• Keep nil-by-mouth
• Consider NGT for decompression
• Supportive Tx (IV hydration; IV electrolyte replacement; transfuse if Hb < 80; pain killers
• Treat spetic shock if present (not in this case)
• IV corticosteroids 100mg 6 hrly

Question 29

Q12. What diagnostic features would you expect the biopsy taken on sigmoidoscopy to show?

Question 30

Q13. What are the two clinical subtypes of this bowel disease, and differences in their clinical presentation, histology and long term treatments options, medical and surgical?

Question 31

Q14. How is family history relevant in this case? Is there any other history you will like to find out in light of this family history?