Faeces is temporarily stored in the rectum and expelled from the body via the anus. An anal fissure is a tear or split in the lining of the anus. The symptoms and signs include pain when passing a bowel motion and bright red blood from the anus. The problem is common in children younger than one year, and affects around eight out of 10 babies. A person's susceptibility to anal fissures tends to decline with age. Common causes in adults include constipation and trauma to the anus. Around half of cases heal by themselves with proper self-care and avoidance of constipation. However, healing can be a problem if the pressure of passing bowel motions constantly reopens the fissure. Treatment options include surgery.
The symptoms and signs of an anal fissure include:
- Anal pain.
- Pain when passing a motion and for some time afterwards.
- Bright red blood from the anus.
- Blood on the surface of stools.
- Blood smears on the toilet paper.
The anus permits bowel continence, which is voluntary control over the passage of bowel motions. Waste is massaged down the length of the large intestine by waves of muscular contractions. Once the excess water is removed, the waste is temporarily stored in the rectum. The rectum joins to the anus, which is a short tube containing a muscular ring (sphincter) that can be opened at will to allow the expulsion of faeces (poo). The membranous lining of the anus is called the anal mucosa. An anal fissure is a tear in the anal mucosa.
A Range of causes
Some of the causes of an anal fissure include:
- Anal injury.
- Child birth.
- Crohn's disease.
- Chronic constipation.
- Cancer of the rectum.
- Inflammation of the anus and rectum.
- Passing a dry, hard stool.
- Rough or excessive wiping of the anus after passing a motion.
Anal fissures aren't associated with more serious diseases, such as bowel cancer. Some of the possible complications of an anal fissure can include:
- Chronic anal fissure - the tear fails to heal. Over time, this can cause extensive scar tissue at the site of the fissure.
- Anal fistulas - abnormal 'tunnels' join the anal canal to surrounding organs, usually other parts of the bowel.
- Anal stenosis - the anal canal becomes abnormally narrowed either due to spasm of the anal sphincter or contraction of the resultant scar tissue.
An anal fissure is diagnosed using a number of tests including:
- Physical examination
- Inspection of the anus and rectum with a slender instrument.
Medical treatment for an anal fissure may include:
- Pain killing medications.
- Anaesthetic creams.
- Nitroglycerin creams.
Self-help treatment options
Be guided by your health care professional, but general suggestions include:
- Apply petroleum jelly to the anus.
- Use baby wipes instead of toilet paper.
- Shower or bathe after every bowel motion.
- Drink six to eight glasses of water every day.
- See your chemist for advice on ointments specific for anal pain.
- Take regular sitz baths, which involves sitting in a shallow bath of warm water for around 20 minutes.
Many cases of anal fissures are caused by chronic constipation. Suggestions include:
- Eat a high fibre diet.
- Drink plenty of water to help soften stools.
- Consider using a fibre supplement.
- Make sure to wipe gently after going to the toilet.