Anal fissures are small tears in the epithelium of the anus that can be intensely painful.
Most anal fissures are caused due to straining during bowel movements, constipation or repeated diarrhoea. They are
equally common in both sexes, and most frequently affect people aged 15 – 40 years.1 Women giving birth are
at increased risk of developing anal fissures due to pressure on the perineum. Spasm of the anal sphincter or local ischaemia
can predispose people to, or worsen, anal fissures.
Atypical anal fissures may develop in people with Crohn's disease, sexually transmitted diseases (particularly
HIV, syphilis and herpes simplex), anal cancer, local trauma (anal intercourse), tuberculosis or receiving chemotherapy.2,
Spontaneous resolution occurs in one-third of people, usually within six weeks. Anal fissures that persist longer than
this are considered chronic and should be managed more intensively. Topical glyceryl trinitrate is now available, fully
subsidised, with Special Authority, as a treatment option for people who have had an anal fissure for at least three weeks.
Where medical management fails to resolve symptoms and help heal the fissure, referral to secondary care for surgery or
botulinum toxin treatment is usually required.
Symptoms and history usually indicate anal fissures
Anal fissures can usually be diagnosed based on the patient’s description of their condition and a brief history, although
an examination is also required.
Intense pain during defecation that often persists for one to two hours afterwards is the primary symptom of an anal
fissure.1 Patients will usually also have noticed the presence of blood on the toilet paper, and may report
a tearing sensation during bowel movements.
Complications may occur in some people, including: failure to heal/chronic fissure, an anorectal fistula, infection
and/or abscesses may develop or faecal impaction can occur due to intense and intolerable pain during defecation.
Perform an examination to help confirm a diagnosis. Anal fissures are not always visible on examination;
however, examination is useful for ruling out other causes of pain and bleeding such as haemorrhoids, abscesses and viral
ulcers. In 90% of cases, anal fissures form on the posterior midline of the anus. Typical features of a chronic anal fissure
include an ulcerated lesion, a sentinel pile at the base of the fissure (resulting in a permanent skin tag) and enlargement
of the anal papillae.