ANORECTAL CONDITIONS

Question 1

What are haemorrhoids?

Answer 1

Capillary bed cushion which result from enlarged venous plexuses at the lower end of the anal mucosa. They are caused by raised intra-abdominal pressure which inhibits venous return and hence causes venous engorgement.

Question 2

What are the risk factors for developing haemorrhoids?

Answer 2

Constipation
Low fibre diet
Excessive straining to pass urine or stool
Pregancy - both because of pressure and oestrogen-related venous dilation

Question 3

How do people with haemorrhoids typically present?

Answer 3

Rectal bleeding, which may coat the stool, drip into the toilet or just be on the toilet paper.
Perianal irritation and itching.
Symptoms are intermittent and precipitated by constipation.

Question 4

How might you investigate someone who presents with a history consistent with haemorrhoids?

Answer 4

Proctoscopy

Question 5

Where in the anal canal do haemorrhoids typically develop?

Answer 5

At the 3, 7 and 11 positions with the patient supine in the a trendelenberg position (face upwards with head below pelvis)

Question 6

How are haemorrhoids classified?

Answer 6

First degree - no prolapse
Second degree - prolapse on defecation but spontaneous reduce
Third degree - Require digital reduction or persistently prolapsed

Question 7

What are the complications of haemorrhoids?

Answer 7

Thrombosis of the haemorrhoids is painful and irreducible. It is however a self limiting condition that eventually results in atrophy and fibrosis. Leaves behind visible anal tags.

Question 8

How are haemorrhoids treated?

Answer 8

Mild cases can be improved by reversing constipation through diet advice or defecation therapy.
Injection of sclerosant or elastic band ligation may be needed in troublesome cases
Surgical resection is reserved for irreducible prolapsed and problematic cases.

Question 9

What is an anal fissure?

Answer 9

A tear or ulcer that develops in the lining of the anal canal. The pain associated with the tear causes anal spasm which in turn aggravates the constipation that caused the condition originally.

Question 10

Where in the anal canal are most anal fissures found?

Answer 10

90% are in the posterior margin

Question 11

What are the clinical features of an anal fissure?

Answer 11

Rectal pain during defecation
Rectal bleeding
Rectal examination is often not possible due to extreme pain.

Question 12

How are anal fissures treated?

Answer 12

Acute fissures - local anaesthetic and prevention of constipation with bulking agent or osmotic laxative

Chronic fissuring - surgical. Lateral internal sphincterotomy.
Glyceryl trinitrate ointment may help.

Question 13

What is pruritus ani?

Answer 13

Redness around the anus. Usually secondary to poor hygiene and incontinence. Associated conditions such as haemorrhoids, threadworm infestation or fungal infection should be excluded.

Question 14

How is pruritus ani treated?

Answer 14

Good personal hygiene
Keep area dry
Avoid topical steroids

Question 15

What is rectal prolapse?

Answer 15

Where the walls of the rectum begin to prolapse out through the anal canal. Partial prolapse is when the prolapse involves only the mucosa and the prolapse does not occur beyond the external sphincter. Complete prolapse involves both the mucosa and the muscles layers and they prolapse outside the anal sphincter.

Question 16

What causes rectal prolapse?

Answer 16

Excessive straining when opening bowels.

Question 17

What are the clinical features of rectal prolapse?

Answer 17

Tenesmus - feeling of incomplete defecation
Rectal bleeding - mucosal ulceration
Incontinence of faeces can be a factor

Prolapse can be seen when patient strains

Question 18

How would investigate someone with suspected rectal prolapse?

Answer 18

Sigmoidoscopy
Defecating proctogram
Endoscopic ultrasound - determines whether there is muscle damage

Question 19

How is rectal prolapse treated?

Answer 19

Mild - High fibre diet, Avoiding straining

Severe - posterior fixation of the rectum to the sacral wall. Sphincter repair may also be necessary with incontinence.

Question 20

What is an anorectal abscess?

Answer 20

An abscess adjacent to the anus. It arises from an infection at one of the anal glands which leads to inflammation and abscess formation which spreads along the anal duct through the external anal sphincter in the wall of the anal canal.

Question 21

Which chronic patients are more likely to develop an anorectal abscess?

Answer 21

Diabetes
Crohn’s disease
Immunosuppressed

Question 22

What are the clinical features of an anorectal abscess?

Answer 22

Pain
Fluctuant mass sitting just beneath inflamed skin - perianal or ischiorectal abscess
Tender mass on rectal examination - intersphincteric or pararectal abscess
Fever

Question 23

What investigations would you order for someone with a suspected anorectal abscess?

Answer 23

FBC
CRP
Flexible sigmoidoscopy to look for signs of Crohns
MRI to identify location if surgery required.

Question 24

How do you manage someone with an anorectal abscess?

Answer 24

Surgical drainage is required in all cases

Antibiotics to cover skin organisms such as Staph, and gut bacteria including anaerobes.

Question 25

What is an anal fistula (or fistula-in-ano)?

Answer 25

A chronic abnormal communication between the epithelialised surface of the anal canal and the perianal skin. It is a complication of anorectal abscesses. Associated with Crohn’s disease.

Question 26

What are the clinical features of an anal fistula?

Answer 26

Intermittent discharge over the peri-anal area from the fistula.
Fistula itself seen as small area of granulation tissue around anal margin.

Question 27

How is an anal fistula examined?

Answer 27

Often under anaesthesia using probe to establish the site of proximal opening. Can also use a dye which is inserted into the distal opening (fistulogram)

Question 28

How do you treat an anal fistula?

Answer 28

Proximal opening is identified (under anaesthetic) and is laid open and healing by secondary intention occurs. This is providing the external sphincter is not involved. If it is a anorectal surgeon is needed to preserve sphincter.