Fissures are a common condition, comprising roughly 5 percent to 15 percent of a colorectal surgeon’s practice. Men and women are equally affected. Usually the cause is a diet lacking in fiber and fluids, which leads to constipation. A lack of fruit, vegetables, whole grains and nuts in the diet can cause constipation, as can an overload of dairy products like cheese, milk and other calcium-rich foods.
Tears occur in the anoderm, which is a tissue that lines the anal canal and anus, The anoderm has no hair follicles, sweat glands or oily glands (termed sebaceous) and is a very sensitive area with lots of nerves. The anoderm runs the length of the anal canal until reaching the dentate line of the rectum.
People of any age can experience fissures, but they are most common in infants. While most fissures will be cured without any treatment within a couple of months, surgical intervention is sometimes needed to relieve discomfort.
Anal fissures typically are caused by passing hard or large stools; straining during bowel movements; diarrhea that won’t go away; an inflammation caused by Crohn’s disease or other inflammatory bowel movements; and pregnant women who strain during childbirth. In some cases, the fissure can be a sign of anal cancer, tuberculosis, syphilis, herpes, or HIV. In rare cases, insertion of a rectal thermometer, endoscope, ultrasound probe or enema tip can cause a fissure.
Symptoms of an anal fissure include pain during bowel movements that sometimes lasts for hours after the act; bright red blood on toilet paper or visible on the stool; an irritation around the anus, sometimes with itching; a crack in the skin around the anus; or a small skin tag or lump near the fissure.