What is rectal prolapse?

Rectal prolapse occurs when part or all of the wall of the rectum slides out of place, sometimes sticking out of the anus. See an illustration of rectal prolapse.

There are three types of rectal prolapse:

• Partial prolapse (also called mucosal prolapse). The lining (mucous membrane) of the rectum slides out of place and usually sticks out of the anus when you strain to have a bowel movement. The condition may be confused with internal hemorrhoids. (See an illustration of a hemorrhoid.) Partial prolapse is most common in children younger than 2 years.
• Complete prolapse. The entire wall of the rectum slides out of place and usually sticks out of the anus. At first, this may occur only during bowel movements. Eventually, it may occur when you stand or walk, and in some cases the prolapsed tissue may remain outside your body all the time.
• Internal prolapse (intussusception). One part of the wall of the large intestine (colon) or rectum may slide into or over another part, like the folding parts of a telescope. The rectum does not stick out of the anus. (See an illustration of intussusception.) Intussusception is most common in children and rarely affects adults. In children, the cause is usually not known. In adults, it is usually related to another intestinal problem, such as a growth of tissue in the wall of the intestines (such as a polyp or tumor).

In severe cases of rectal prolapse, a section of the large intestine drops from its normal position as the tissues that hold it in place stretch. Typically there is a sharp bend where the rectum begins. With rectal prolapse, this bend and other curves in the rectum may straighten, making it difficult to keep stool from leaking out (fecal incontinence).

Rectal prolapse is most common in children and older adults, especially women.

What causes rectal prolapse?

Many conditions increase the chance of developing rectal prolapse. Risk factors for children include:

• Cystic fibrosis. A child who has rectal prolapse with no obvious cause may need to be tested for cystic fibrosis.
• Having had surgery on the anus as an infant.
• Malnutrition.
• Deformities or physical development problems.
• Straining during bowel movements.
• Infections.

Risk factors for adults include:

• Straining during bowel movements because of constipation.
• Tissue damage caused by surgery or childbirth.
• Structural conditions present since birth.
• Weakness of pelvic floor muscles that occurs naturally with age.

What are the symptoms?

The first symptoms of rectal prolapse may be:

• Leakage of stool from the anus (fecal incontinence).
• Leakage of mucus or blood from the anus (wet anus).

Other symptoms of rectal prolapse include:

• A feeling of having full bowels and an urgent need to have a bowel movement.
• Passage of many very small stools.
• The feeling of not being able to empty the bowels completely.
• Anal pain, itching, irritation, and bleeding.
• Bright red tissue that sticks out of the anus.

How is rectal prolapse diagnosed?