13 March 2019 In most cases, when it is not associated with other diseases, an anal fissure consists of a single lesion , located on the posterior median line of the anus. For anatomical reasons, fissures located on the anterior median line are common in women and more frequent than in men. Anal fissures can occur at any age and affect men and women in similar numbers. They can be acute (appear suddenly) or chronic (remain for some time or reoccur frequently). What causes anal fissures? Anal fissures often occur in patients who suffer with constipation and are the result of trauma due to efforts during defecation and the passing of large, hard stools. They may also occur in patients with diarrhoea involving several daily episodes and in some inflammatory processes of the anorectal area. Although anal fissures are mainly caused by trauma, there are other possible causes , including: Rectal cancer; Crohn’s disease; Leukaemia; Various infectious diseases of bacterial and viral origin. Anal fissures may become chronic as a result of spasm or hypertonia (very strong contractions) of the anal sphincter muscle fibres. The relaxation of the sphincter as it allows the passage of the stool and subsequent return to a state of spasm causes the edges of the fissure to separate and become worse. In addition, permanent spasm of the sphincter creates an area of insufficient blood circulation in the mucous membrane that covers it. The separation of the edges of the fissure and inadequate blood circulation in the area are the 2 main factors preventing it from healing. What are the symptoms of anal fissures? Typical symptoms of anal fissure are as follows: Sharp pain during defecation, which may persist for some time afterwards; A small to moderate amount of bright red blood visible in stools and/or on toilet paper. Patients may avoid defecating as a result of the intense pain it causes. However, this usually leads to the formation of large, hard stools. Passing these stools will worsen the fissure , either directly by trauma or indirectly by aggravating sphincter pain and spasm. In some cases, patients may also experience anal itching and a foul-smelling discharge. How is anal fissure diagnosed? Anal fissure is diagnosed on the basis of: The patient's medical history; Symptoms present at the time of diagnosis; Observation of the anal region. Where symptoms persist and anal fissures are not located on the midline of the body, further examination is required. This is done under general anaesthesia , as there are also diseases in which anal fissures occur and/or which have similar symptoms. How are anal fissures treated? Anal cracks often heal spontaneously . In other cases, medical treatment and occasionally surgical treatment is required. In around 80% to 90% of cases, acute fissures can only be treated medically . However, in the case of chronic fissures , it is estimated that this treatment has only been successful in 40% of cases. The aim of medical treatment is to: Regulate intestinal transit; Relax the anal sphincter; Reduce pain; Promote healing. In the case of fissures that do not respond to medical treatment, in which pain and/or bleeding persists and fissures are recurrent, surgical treatment should be considered. Usually, surgery consists of a minor operation involving the division of a small section of the internal anal sphincter muscle (lateral internal sphincterotomy). The surgery aims to reduce sphincter spasm and complaints of pain , making it easier for the fissure to heal. Cutting this muscle rarely interferes with the sphincter's functional capacity (i.e. its capacity to control gas and stools). This operation can be performed at a day hospital ,without the patient having to spend the night in the hospital. Full healing takes 3 to 4 weeks, although the pain will go away within a few days. More than 90% of patients who undergo surgical treatment do not suffer with anal fissures again. How can you prevent anal fissures from developing? Ensuring regular bowel transit is one of the most important measures. Depending on the patient’s situation (constipation or diarrhoea), this can include making dietary changes with a view to producing softer stools (high fibre diet and increased fluid intake) or to correct the causes of diarrhoea. Sitting in warm water for 10-20 minutes several times a day can: Help relieve pain; Encourage relaxation of the anal sphincter and healing. Occasionally, depending on the patient's current situation, creams and suppositories may be used, together with other treatments with anti-inflammatory action or which counteract muscle spasm. The following measures can also help prevent anal fissures from occurring : Keeping the anal area clean; Using soft or moist toilet paper; Timely treatment of constipation or diarrhoea. Anal fissure are part of coloproctology, which is an area by gastroenterologists and general surgeons. This article was written with the support of general surgeons from the Hospital da Luz network. The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.
