An anal fissure is a tear in the lining of the anal canal, which may occur following the passage of a hard stool.
This can result in often severe pain with the passage of stool. The pain is typically ‘sharp’, ‘tearing’, ‘like passing glass’ or can be a deep-seated throbbing pain. The pain may last minutes to hours. There may be an associated small amount of bright-red bleeding seen on the toilet paper.
THE TEAR RESULTS FROM INITIAL TRAUMA
The tear results from an initial trauma, which may be due to the passage of a hard stool, or the precipitating event may not be recognised. The pain results in muscle spasm, which exacerbates the pain. Furthermore, the muscle spasm impairs blood flow to the fissure, which in turn prevents healing. This allows a continuous cycle of tearing, pain, muscle spasm, lack of blood flow, poor healing and further tearing.
Treatment is aimed to break the cycle. Initial treatment may be topical creams to relax the muscle sphincter (e.g. topical GTN (Rectogesic) or topical diltiazem). Warm baths may help lower the muscle pain and provide symptomatic relief. Strong pain killers should be avoided as they can result in constipation leading to further trauma.
UNLIKELY TO HEAL ON ITS OWN
An acute fissure is unlikely to heal on its own if the symptoms have persisted after six weeks. At this stage, a more definitive relaxation of the sphincter muscle is required. This can be through an injection of botox to the sphincter, or with a minor surgical technique known as a sphincterotomy. The precise course of treatment needs to be tailored to the individual patient.
An anal fissure may be associated with other diseases (such as Crohn’s disease, an inflammatory condition), or the symptoms may reflect an alternative diagnosis. If the symptoms fail to respond to a single short-course of treatment (e.g. topical creams), then investigation is usually warranted. Particular warning symptoms include pain NOT associated with defecation, bleeding mixed in with the stool, new incontinence, a recent change in bowel habits, or a personal or family history of colonic polyps, bowel cancer or inflammatory bowel disease.
OTHER CONDITIONS WE TREAT
n anal fistula is an abnormal connection from just inside the anal canal usually extending to the skin overlying the buttock
Haemorrhoids are the the enlargement of a small network of blood vessels just beneath the lining of the anal canal.