Anal fissure causes severe pain on defecation, often described as 'like passing broken glass'. The pain may continue for 1 to 2 hours and can also be burning in nature.
A small amount of fresh red blood is often passed on the stool.
On examination of the anus, there is often marked spasm of the sphincter muscles, with significant tenderness often precluding digital examination.
Initial treatment should include either topical glyceryl trinitrate or diltiazem, along with a programme of supportive care.
Resistant or chronic fissures may benefit from botulinum toxin A, and most cases can be cured by surgical sphincterotomy or anal advancement flap.
Anal fissure is a split in the skin of the distal anal canal characterised by pain on defecation and rectal bleeding. It is a common condition in young to middle-aged adults and may occur in 1 in 350 people. It is the second commonest gastro-intestinal complication of pregnancy after haemorrhoids. The pain is described as severe (often described as 'like passing broken glass') and has a serious negative effect on quality of life.
History and exam
Key diagnostic factors
- presence of risk factors
- pain on defecation
- tearing sensation on passing stool
- fresh blood on stool or on paper
- anal spasm
Other diagnostic factors
- intermittent symptoms
- sentinel pile
- fissure visible on retraction of buttock
- hard stool
- opiate analgesia
1st investigations to order
- clinical diagnosis
Investigations to consider
- anal manometry
- anal ultrasound
- Crohn's disease
- Treatment algorithm for anal fissure
- Clinical practice guideline for the management of anal fissures
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