Rectal bleeding

Question 1

How is the likely cause of rectal bleeding assessed according to the age of the patient?

Answer 1

Younger patients more likely to be inflammatory/anal fissure/haemorrhoids

Older patients (over 50) more likely to be malignant

Question 2

What are the key aspects of a rectal bleeding history?

Answer 2

Quantity and nature of the bleeding- e.g. colour, mixed with stool?
Unexplained weight loss
Change in bowel habit
Tenesmus
Anal symptoms e.g. pain, itching
FHx bowel problems
PMH and previous surgical history
Drug history e.g. anticoagulants, NSAIDs

Question 3

What blood tests might be appropriate in a patient with rectal bleeding?

Answer 3

Full blood count
Iron studies
Coagulation studies
CRP and white cell count
Faecal calprotectin
CEA

Question 4

What is the clinical usefulness of faecal calprotectin?

Answer 4

Has a high positive predictive value for inflammatory bowel disease

Question 5

Which investigations in secondary care may be indicated for patients with rectal bleeding?

Answer 5

Flexible sigmoidoscopy
Colonoscopy +/- biopsy
Virtual colonscopy (CT colonography)

Question 6

Malignant/pre-malignant causes of rectal bleeding? (2)

Answer 6

Anal intra-epithelial neoplasia/anal cancer

Adenoma/adenocarcinoma of the colon

Question 7

Ano-rectal causes of rectal bleeding? (2)

Answer 7

Haemorrhoids

Anal fissure

Question 8

How is faecal continence maintained?

Answer 8

Smooth muscle of the internal anal sphincter, under involuntary control
Striated muscle of the external anal sphincter, under voluntary control via the pudendal nerve

Question 9

Which muscle does the external anal sphincter blend with?

Answer 9

Puborectalis (of levator ani)

Question 10

What are haemorrhoids?

Answer 10

Prolapsed and enlarged anal cushions, containing arteriovenous communications

Question 11

Main clinical features of haemorrhoids?

Answer 11

Bleeding (separate from the stool)

Acheing pain on defaecation

Question 12

Clinical classification of haemorrhoids?

Answer 12

I- bleed but don’t prolapse
II- prolapse during defaecation but reduce spontaneously
III- prolapsed constantly but can be reduced manually
IV- irreducible

Question 13

Conservative management of piles?

Answer 13

If constipation is a feature, treat this (e.g. plenty of fluids, stool softener, dietary fibre)
Ligation of the mucosa proximal to the haemorrhoid (“pulls up” the prolapse)

Question 14

Surgical management of haemorrhoids?

Answer 14

Haemorrhoidectomy

Question 15

Where are anal fissures most commonly observed?

Answer 15

Posterior midline of the anal canal

Question 16

What is the underlying pathophysiology of anal fissuring?

Answer 16

Ischaemia in the base of the fissure ulcer, associated with high sphincter pressure

Question 17

Main clinical features of anal fissure?

Answer 17

Pain on defaecation and on wiping; may persist for many hours after
Constipation (may be provoking factor, or an involuntary response to the pain)
Bleeding (outlet-type)

Question 18

Management of anal fissure? (3)

Answer 18

Stool softeners and management of constipation
Chemical sphincter relaxation with GTN/diltiazem cream
Surgical- lateral sphincterotomy

Question 19

Inflammatory causes of rectal bleeding? (3)

Answer 19

Colitis/proctitis (Crohns/UC/indeterminate colitis)
Diverticulitis
Infective gastroenteritis (rarely)

Question 20

Rectal bleeding + abnormal blood vessels on colonscopy?

Answer 20

Angiodysplasia of the colon

Question 21

Treatment for angiodysplasia of the colon?

Answer 21

Endoscopic ablation of abnormal vessels