Pediatric Rectal Prolapse

Updated: Nov 13, 2017
  • Author: Jaime Shalkow, MD, FACS; Chief Editor: Carmen Cuffari, MD  more...
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Overview

Practice Essentials

Rectal prolapse refers to the extrusion of some or the entire rectal wall through the external anal sphincter.

Although less common in Western societies, pediatric rectal prolapse is a relatively common benign disorder in children. However, without proper treatment, it can become a lifestyle-limiting, chronic condition. Most cases are self-limiting, with prompt resolution after conservative measures aimed at correcting the associated underlying process.

In children, rectal prolapse should always be considered a presenting sign of an underlying condition, and not a disease entity unto itself.

Rectal prolapse starts as a mucosal extrusion from the mucocutaneous junction, which may eventually progress to full-thickness prolapse. It is one of the first surgical entities ever described in medicine. (see the image below).

Image of young patient with full-thickness rectal Image of young patient with full-thickness rectal prolapse with multiple circular folds seen on exposed mucosa.

 

Rectal prolapse and its etiology were first described in 1912 by Moschcowitz. Rectal prolapse in childhood was first highlighted in 1939 by Lockhart-Mummery, [1] who attributed the condition to malnutrition and careless nursing, but also acknowledged diarrheal and wasting illnesses as contributing factors. Lockhart-Mummery’s preferred operative treatment was linear cauterization of the prolapsed rectum, with recurrences treated by 5% phenol injection.

Loss of the normal sacral curvature that causes a vertical tube between the rectum and the anal canal has been described as a causative factor. Straining during defecation predisposes children with constipation, diarrhea, or parasitosis to prolapse, as does childhood laxative usage. About 60-70% of patients have fecal incontinence. [2] The prolapse can spontaneously reduce or may require digital reduction.

One classification of rectal prolapse divides the entity into true prolapse (protrusion of all layers of the rectum) and procidentia (herniation of only the mucosa). However, this classification is confusing and nonspecific and therefore, fallen out of use.

The most used classification for rectal prolapse was described in 1971 by Altemeier et al, who divided the entity into the following types [3] :

  • Type I - Protrusion of redundant mucosa, termed false prolapse; usually associated with hemorrhoids
  • Type II - Intussusception without sliding hernia of the cul-de-sac; it occupies the rectal ampulla but does not continue through the anal canal; the most common symptom is fecal incontinence, but solitary ulcers in the anterior rectal mucosa can be seen
  • Type III - Complete, full-thickness rectal wall prolapse, associated with a sliding hernia of the Douglas pouch. It is the most frequent type
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Anatomy

The anal canal extends cephalad from the anal verge to the anorectal ring. The rectum extends from this point to the sacral promontory.

Upon histologic examination, the anal canal consists of mucosa, submucosa, and 2 muscular layers: the internal anal sphincter (IAS), which is a continuation of the circular muscle of the rectum, and (2) the external anal sphincter (EAS), which lies outside the IAS as an elliptic cylinder, continuous with the puborectalis muscle superiorly. The surgical anal canal includes this entire muscular sphincter mechanism (see the images below).

Levator ani muscle is shown in red. It includes il Levator ani muscle is shown in red. It includes ileococcygeus (stretches during defecation and labor), pubococcygeus (maintains integrity of pelvic floor), and puborectalis muscles (closes the anorectal canal as a sling).
Deep, superficial, and subcutaneous external sphin Deep, superficial, and subcutaneous external sphincter.
Anatomy of internal and external anal sphincter me Anatomy of internal and external anal sphincter mechanisms.

The many and varied procedures described for the treatment of rectal prolapse attempt to create a fixation of the anorectal mucosa to the submucosa, or the rectal wall to perirectal tissues.

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Pathophysiology

A pelvic floor defect with levator ani muscle diastasis and a deep endopelvic fascia represent the pathophysiologic of the disease. Patients with rectal prolapse have lost the normal semihorizontal rectal position; they also have weak muscle insertions to the pelvic walls and sacrum, and an abnormally deep Douglas pouch. A redundant rectosigmoid and weaker / wider anal sphincter are common.

The normal resting tone of the anal sphincter decreases in response to rectal distention. In 1962, Porter found that patients with rectal prolapse have a profound and lengthy response and weakened tone of the levator ani muscles. [4] Whether this is a causative factor or a secondary finding is not clear, since the prolapse begins above the pelvic musculature.

Rectal prolapse has been associated with a myriad of conditions, including:

  • Increased intra-abdominal pressure due to straining (as often occurs in toilet training and constipation)
  • Parasitic disease (the most common cause of rectal prolapse in developing countries)
  • Neoplastic disease
  • Malnutrition (loss of ischiorectal fat pad) - Worldwide, this is possibly the most common condition associated with pediatric rectal prolapse; the loss of ischiorectal fat reduces perirectal support
  • Meningomyelocele
  • Surgical repair of anorectal malformation
  • Fecal incontinence and diarrhea [5, 6]
  • Chronic constipation [7]
  • Neuromuscular disorders
  • Mental challenge [8]
  • Poor sacral root innervation (Spina bifida)
  • Bladder or cloacal exstrophy [9]
  • Scleroderma [10]
  • Hirschsprung disease (especially in ultrashort aganglionic segment, which acts as subocclusion, favoring prolapse) [11]
  • Rectal polyps (the polyp acts as a leading point) [12]
  • Shigellosis in neonates [14]

Cystic fibrosis deserves special attention as cystic fibrosis may cause rectal prolapse in children. In the past, rectal prolapse was described in up to 20% of individuals with cystic fibrosis. However, current reports estimate an incidence of 3% of children with the disease. [15, 16] Potential mechanisms include bulky bowel movements, coughing paroxysms, and undernutrition. It is most frequently seen in toddlers, but it can occur at any age (triggered by cough)

Clinical clues to cystic fibrosis include oily, malodorous, or floating stools; poor growth; wheezing or other respiratory symptoms; and digital clubbing. The absence of respiratory symptoms and normal findings upon physical examination do not necessarily exclude this diagnostic possibility. Sweat chloride and genetic testing confirm the diagnosis.

Most cases of childhood rectal prolapse occur in children younger than 4 years, with the highest incidence during the first year of life. Anatomic considerations related to this early presentation include the vertical course of the rectum along the straight surface of the sacrum, a relatively low position of the rectum in relation to other pelvic organs, increased mobility of the sigmoid colon, relative lack of support by the levator ani muscle, loose attachment of the rectal mucosa to the underlying muscularis, and absence of Houston valves, seen in about 75% of infants.

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Etiology

Several predisposing factors have been identified, chronic constipation and straining being most common (52%).

Other causes include diarrhea (15%), [5] rectal parasites [17] , neuromuscular and pelvic nerve disorders, myelomeningocele, bladder and cloacal exstrophy, Hirschsprung disease, high anorectal malformations, [18] cystic fibrosis, chronic respiratory infections and cough, [19] lymphoid hyperplasia, rectal polyps, and shigellosis. [20] Rectal prolapse has been described in a case of Clostridium difficile –associated pseudomembranous colitis in a child. [21]

Broden and Snellman demonstrated cineradiographically, that the entity implies a circumferential intussusception of the rectum, with its origin 3 inches above the anal margin. [22]  

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Epidemiology

In adults, rectal prolapse is six times more common in females than in males. 75% of patients have history of constipation, which stretches the pelvic floor and the anal sphincter mechanism, predisposing them to the disease.

In children, incidence is higher during the first year of life, after which it becomes increasingly infrequent. It is slightly more common in boys than in girls. 

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Prognosis

Most cases reduce spontaneously. Otherwise, venous stasis, edema, and ulceration ensure. Longstanding or frequent recurrent prolapse episodes lead to proctitis.

Approximately 10% of patients who experience rectal prolapse as children continue to be symptomatic into adulthood. Over 90% of children who prolapsed during the first 3 years of life, respond to conservative treatment by age 6. Spontaneous resolution is much less likely in children who develop their first episode of prolapse after age 4 years.

After a surgical rectopexy, continence is achieved in 92% of patients. Resective procedures demonstrate lower recurrence rates. Recovery of continence after surgery is not immediate, it may take up to a year.

Nwako et al reported a 100% success rate with the Lockhart-Mummery procedure, which involves packing the presacral space with gauze through a posterior approach, with excision of the prolapsed mucosa. [23]

Hight et al recommend linear cauterization of the rectal mucosa, with a 98% success rate in 72 patients. [24]

 

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