Rectal prolapse is a painless protrusion of the rectum through the anus.
Rectal prolapse causes the rectum to turn inside out, so that the rectal lining is visible outside the body as a dark red, moist, fingerlike projection from the anus. Bleeding from the rectum can occur, and an uncontrolled loss of urine (urinary incontinence) is a frequent symptom. Less commonly, the rectum protrudes into the vagina (rectocele—see Pelvic Floor Disorders: Rectocele).
A temporary prolapse of only the rectal lining (mucosa) often occurs in otherwise healthy infants, probably when the infant strains during a bowel movement, and is rarely serious. In adults, prolapse of the rectal lining tends to persist and may worsen, so that more of the rectum protrudes. A complete prolapse of the rectum is called procidentia. This condition occurs most often in women older than age 60.
To determine the extent of a prolapse, a doctor examines the area while the person is standing or squatting and straining. By feeling the anal sphincter with a gloved finger, a doctor often detects diminished muscle tone. A sigmoidoscopy, colonoscopy, or barium enema x-rays (see Diagnosis of Digestive Disorders: Endoscopy) of the large intestine may reveal an underlying disease.
In infants and children, a stool softener eliminates the urge to strain. Strapping the buttocks together between bowel movements usually helps the prolapse heal on its own.
In adults, surgery is usually needed to correct the problem. Surgery often cures procidentia. During one kind of abdominal operation, the entire rectum is lifted, pulled back, and attached to the sacral bone in the pelvis. In another, a segment of the rectum is removed, and the remainder of the rectum is stitched to the sacral bone.
For people who are too weak to undergo surgery because of extreme old age or poor health, surgery on the rectum is preferred to surgery on the abdomen. One type of surgery on the rectum is done by inserting a wire or plastic loop to encircle the sphincter in a technique called the Thiersch procedure. Alternatively, a segment of the rectum or the excess lining of the rectum may be cut out (excised).
Last full review/revision May 2012 by Parswa Ansari, MD