Approach Considerations
Rectal prolapse is usually only a symptom, and evaluation should focus on discovery of an underlying disorder.
In children, rectal prolapse is usually a benign condition that calls for evaluation of the underlying condition. Evaluate pediatric patients for cystic fibrosis; a significant percentage are affected with this disorder.
Laboratory Studies
The only pertinent laboratory studies for a patient with rectal prolapse are those studies that are dictated by the patient’s age and comorbidities. There are no specific tests that aid in the evaluation of rectal prolapse itself.
Perform a sweat chloride test for pediatric patients; as many as 11% of children with rectal prolapse have cystic fibrosis. Consider a stool examination and culture for infectious agents, particularly in pediatric patients.
Barium Enema and Colonoscopy
Before initiating surgical treatment of rectal prolapse (see Treatment), it is important to evaluate the entire colon in order to exclude any other colonic lesions that should be simultaneously addressed. The presence of such lesions may affect the choice of the procedure to be performed.
Evaluation of the colon may be accomplished by means of colonoscopy or barium enema. Barium enema is a better indicator of the redundancy of the colon.
Video Defecography
Video defecography is used to help document internal prolapse or to distinguish rectal prolapse from mucosal prolapse if it is not clinically obvious. It is not necessary for clinically diagnosed full-thickness rectal prolapse. Defecography may reveal intussusception of proximal colon or pelvic outlet obstruction.
Radiopaque material (usually barium paste) is instilled into the rectum, and the patient is asked to defecate on a radiolucent toilet. Spot films and videotapes are made and can be used to determine if the rectum intussuscepts on defecation.
Rigid Proctosigmoidoscopy
Rigid proctosigmoidoscopy should be performed to assess the rectum for additional lesions, especially solitary rectal ulcers. These ulcers are present in about 10-25% of patients with either internal or full-thickness prolapse. If ulceration is present, the area appears as a single ulcer or as multiple ulcers on the anterior rectal wall. The edges are often heaped up, and the area may be bleeding.
Biopsy should be performed to confirm the diagnosis and to exclude other pathology. Solitary rectal ulcers can usually be identified by an experienced pathologist. The prolapsed rectum may have ulcerated mucosa but is otherwise histologically normal.
Other Tests
Anal-rectal manometry is sometimes used to evaluate the anal sphincter muscles. In almost all patients, the results show a decrease in resting pressure in the internal sphincter and an absence of the anorectal inhibitory reflex. The significance of these results is unclear, and most surgeons do not use this test.
The Sitz marker study is occasionally used to measure colonic transit in a patient with constipation and rectal prolapse to help determine the need for colonic resection.
Pudendal nerve terminal motor latency assesses for neurologic injury or dysfunction.
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Rectal prolapse.
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Full-thickness rectal prolapse.
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Marlex rectopexy for rectal prolapse.
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Delorme mucosal sleeve resection for rectal prolapse.
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Altemeier perineal rectosigmoidectomy for rectal prolapse.
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Perineal rectosigmoidectomy for rectal prolapse. Procedure performed by Tracy Arnell, MD, ColumbiaDoctors, New York, NY. Video courtesy of ColumbiaDoctors (https://www.columbiadoctors.org).
