An anal fissure is a small split or tear in the anal mucosa that may cause painful bowel movements and bleeding . There may be blood on the outside of the stool or on the toilet tissue following a bowel movement.

Causes, incidence, and risk factors

Anal fissures are extremely common in young infants but may occur at any age. Studies suggest 80% of infants will have had an anal fissure by age one. Most fissures heal on their own and do not require treatment, aside from good diaper hygeine. However, some fissures may require medical treatment. The incidence of anal fissures decreases rapidly with age. Fissures are much less common among school-aged children than among infants. In adults, fissures may be caused by constipation , particularly when passing large, hard stools, or by prolonged diarrhea. In older adults, anal fissures may be caused by decreased blood flow to the area. Anal fissures are also common in women after childbirth and people with Crohn's disease .

Signs and tests

Inspection

of the rectum

Physical exam of the rectal

mucosa

Treatment

Stool softeners

Dietary adjustment (addition of

bulk -- substances that absorb water while in the intestinal tract)

Cleansing more gently

Petroleum jelly

Sitz bath

Anesthetic ointment, if pain interferes with normal bowel movement

Topical muscle relaxants

These measures generally heal more than 90% of anal fisssures. For fissures that do not heal with these home treatments, injection of botulinum toxin (Botox) into the anal sphincter may be used to temporarily paralyze the anal sphincter muscle and promote healing. Another option for nonhealing fissures is a minor surgicial procedure to relax the sphincter.

Expectations (prognosis)

Anal fissures generally heal quickly without residual problems. However, people who develop fissures are more likely to have them in the future.

Complications

Occasionally, a fissure becomes chronic and will not heal. Chronic fissures may require minor surgery to relax the sphincter.

Calling your health care provider

Call your health care provider if symptoms associated with anal fissure are present, or if the fissure does not heal appropriately with treatment.

Prevention

To prevent anal fissures in infants, be sure to change diapers frequently. To prevent fissures at any age:

Keep the anal area dry

Wipe with soft materials or a moistened cloth or cotton pad

Promptly treat any

constipation or diarrhea

Avoid irritating the rectum