6. A patient with rectal bleed and abdominal pain

Question 1

A 40-year-old man sees his GP complaining of a two month history of increased bowel
frequency, which is associated with loose motions and rectal bleeding. He describes
the bleeding as fresh red, mixed with his motions and occasionally with mucus. He is
otherwise fit and well and had no past surgical history. He does not smoke nor drink
alcohol. He has two siblings aged 40 and 45 who have been diagnosed with polyps
and his father developed colorectal cancer at the age of 67.

Q1. What are the possible diagnoses based on history as above?

Answer 1

IBD
IBS unlikely as blood present
Diverticular disease
Haemorrhoids

Question 2

How can you structure different pathologies causing bleeding? [3]

Answer 2

Whole bowel:
- Crohns
- Coeliac

More common to large bowel:
- UC
- Diverticulitis
- Colorectal cancer
- Ulcerations around rectum

Anal pathologies:
- Haemorrhoids
- Fissures
- Fistulas
- Trauma

Question 3

What is the bleeding like in haemorrhoids? [3]

Answer 3

• Fresh / bright red blood
• Blood on surface of stool
• Blood when they wipe / toilet pan

Question 4

Q2. What investigations should the GP request?

Answer 4

Blood:
- FBC
- Hb
- MCV - microcytic / macrocytic?
- Anaemia
- ESR / CRP for inflammation
- Ferritin / Transferrin
- Clotting screen: check for blood disorder

U&Es

Stool:
- Faecal calprotectin: IBD
- MC & S: organic causes
- anti tTGA
- FIT test

PR exam:
- Blood
- Lumps
- Fissures
- Internal / external haemorrhoids
- If there is stool - colour and mucus

Colonoscopy

Question 5

What are causes of B12 and folate deficiency? [2]

Answer 5

Coeliac disease
Pernicious anaemia

Question 6

What is this? [1]

Answer 6

Anal fissure

Question 7

Which stool test would you use to investigate bowel malignancy? [1]

Answer 7

FiT Test

Question 8

A few days after seeing his GP, he presents to the Emergency Department with three
days of central abdominal pain and vomiting. On examination he is pale. Examination
of the abdomen is normal, there are no palpable groin herniae and examination of the
rectum is normal. Sigmoidoscopy examination is normal.

Q4. What is the differential diagnosis based on the clinical presentation in
ED? [5]

Answer 8

Bowel obstruction
Gastroenteritits
Appendicitis
Pancreatitis
Toxic megacolon
Ruptured AA
DKA

Question 9

Describe the symptoms of a ruptured AA [5]

Answer 9

classical triad of:
- pain in the flank or back, hypotension and a pulsatile abdominal mass; however, only about half have the full triad. The patient will complain of the pain and may feel cold, sweaty and faint on standing

Question 10

Explain these:
* Haemoglobin 9.1 g/dL (13 - 18)
* MCV 76 fL (80 - 99)

Answer 10

IDA microcytic anaemia

Question 11

Explain these results
* Sodium 149 mmol/L (135 - 145)
* Potassium 3.2 mmol/L (3.5 - 5)

Answer 11

Vomiting [1]

Question 12

Explain these results [1]

Creatinine 149 µmol/L (70 - 120) [1]

Answer 12

Pre-renal AKI from vomiting

Question 13

Explain these results:

ALT 338 u/L (3 - 35)
AST 102 u/L (3 - 35)
ALP 21 u/L (30 - 35)

Answer 13

Derenged LFTs

ALP low:

Question 14

What is a good marker for pancreatitis? [1]

Answer 14

Amylase

Question 15

Which is the next most appropriate investigation for this man while in ED?
Why? [3]

Answer 15

Erect CXR:
- Bowel obstruction / burst causing pneumoperitoneum

Abdominal XR:
- Bowel dilation
- Obstruction

CT Abdo Pelvis: shows more detailed scan, but takes longer to occur

Question 16

What does an AXR miss, which requires CT abdo/pelvis to diagnose? [1]

Answer 16

Small bowel obstruction: only 60% sensitive when using AXR

Question 17

Q7. What does the XR abdomen show?

Answer 17

Small bowel:
- More central
- Valvulae conniventes

Question 18

How can you tell if obstruction is large ro small bowel XR? [2]

Answer 18

Large bowel is normally around peripheries

Small bowel has valvulae conniventes (ring like structures all across the bowel)

Large bowel has haustra (go only half way across the bowel)

Question 19

Is this large or small bowel obstruction? [1]

Answer 19

The white lines passing across the full width of the bowel are ‘valvulae conniventes’ - these are only found in the small bowel.

Question 20

What is the 3, 6, 9 rule? [3]

Answer 20

Anything above these measurements would be dilation

< 3 cm: small bowel

< 6cm: colon

< 9cm caecum

Question 21

Q9. How can the diagnosis be confirmed for small bowel obstruction?

Answer 21

CT Abdo / Pelvis

Question 22

Q10. Outline your initial assessment of this man in the emergency department.

Answer 22

1. A-E
2. Fluid resuscitation: 0.9% saline 500 ml
3. IV anti-emetic
4. IV painkillers
5. NG tube: decompresses the stomach.
6. Urine catheter: measure urine input/outputs
7. Refer to general surgery

Question 23

Why is the patient nill by mouth? [1]

Answer 23

Due to bowel obstruction, anything that is given orally will get obstructed and vomited back up

Question 24

Describe the process of drip and suck

Question 25

Q11. What are the causes of small and large bowel obstruction?

Answer 25

Question 26

What is intussecption/

Question 27

What is a closed-loop obstruction?

Question 28

Q13. What are the implications of having a family history of bowel cancer? Is there any other history you will like to find out in light of this family history?

Answer 28

Investigate: **lynch syndrome**: Investigate: **Familial Adenomatous Polyposis** - Condition where you get multiple polyps in colon; increases risk of cancer by 90%

Question 29

How can you differentiate bwetween tumurs on left side of the bowel vs right side? [1] Which side is more common? [1]

Answer 29

**Brighter red coloured faeces** on **left side colon** **Left side** is more **common**: lumen smaller

Question 30

Red flag symptoms for colon cancers related to this case?

Answer 30

1. Unexplained weight loss 2. Blood in stool 3. Changes in bowel habit 4. FH 5. Abdo / rectal mass 6. Unexplained IDA

Question 31

Pneumonic for red flag symptoms? [6]

Answer 31

**ALARMS** Anaemia Loss of weight Anorexia Recent symptoms Masses / Malaena Swallowing difficulty