Anal fissure

Question 1

What are anal fissures?

Answer 1

Anal fissures are longitudinal or elliptical tears of the squamous lining of the distal anal canal.

Question 2

How are anal fissures classified based on duration?

Answer 2

If present for less than 6 weeks, they are defined as acute; if present for more than 6 weeks, they are chronic.

Question 3

What are some risk factors for anal fissures?

Answer 3

Risk factors include constipation, inflammatory bowel disease, and sexually transmitted infections (e.g., HIV, syphilis, herpes).

Question 4

What are the features of anal fissures?

Answer 4

Features include painful, bright red rectal bleeding, and around 90% occur on the posterior midline.

If fissures are found in alternative locations, other underlying causes should be considered (e.g., Crohn’s disease).

Question 5

What is the management for an acute anal fissure?

Answer 5

Management includes softening stool, dietary advice (high-fibre diet with high fluid intake), bulk-forming laxatives, lubricants (e.g., petroleum jelly), topical anaesthetics, and analgesia.

Question 6

What is the first-line treatment for a chronic anal fissure?

Answer 6

Topical glyceryl trinitrate (GTN) is the first-line treatment for a chronic anal fissure.

Question 7

What should be considered if topical GTN is not effective after 8 weeks?

Answer 7

If topical GTN is not effective after 8 weeks, secondary care referral should be considered for surgery (sphincterotomy) or botulinum toxin.