Rectal prolapse in children

INTRODUCTION — This topic discusses the clinical manifestations, diagnosis, and management of rectal prolapse in children.

Rectal prolapse in adults is discussed separately. (See "Overview of rectal procidentia (rectal prolapse)" and "Surgical approach to rectal procidentia (rectal prolapse)".)

DEFINITION AND EPIDEMIOLOGY — Rectal prolapse refers to the extrusion of some or all of the rectal mucosa through the external anal sphincter (figure 1) [1-4]. Rectal prolapse seldom occurs in children who do not have an underlying predisposing condition. Self-limited conditions are more common between infancy and four years of age, with the highest incidence in the first year of life [1,5]. Those presenting beyond 4 years of age usually have a chronic predisposing condition (see below). Observational reports suggest that during childhood, rectal prolapse occurs in higher frequency in boys [6,7].

TYPES — There are two types of rectal prolapse [4]:

●Type I – Type I, also called false procidentia, partial, or mucosal prolapse, involves protrusion of the mucosa only and usually is less than 2 cm long. Partial rectal prolapse produces radial folds at the junction with the anal skin (figure 1).

●Type II – Type II, also known as true procidentia, or complete prolapse, involves full thickness extrusion of the rectal wall and is characterized by concentric folds in the prolapsed mucosa (picture 1). This group is subdivided into three subsets according to the degree of the prolapse:

•First degree – First degree prolapse includes the mucocutaneous junction. The length of the protrusion from the anal verge usually is greater than 5 cm.

•Second degree – Second degree prolapse occurs without involvement of the mucocutaneous junction. The length of the protrusion from the anal verge usually is between 2 and 5 cm.

•Third degree – Third degree prolapse is internal, concealed, or occult and does not pass through the anal verge.

PATHOGENESIS — The following anatomic considerations may account for the increased incidence of rectal prolapse in early childhood [4,8-12]:

●The rectum has a vertical course along the surface of the sacrum and coccyx.

●The rectum is in a relatively lower position than are the other pelvic organs.

●The sigmoid colon has more mobility.

●The levator ani muscle offers relatively little support.

●The redundant rectal mucosa is attached only loosely to the underlying muscularis.

●Houston valves are absent in approximately 75 percent of infants younger than one year of age (Houston valves are prominent mucosal folds that provide structural integrity to the rectum).

Based upon information from anatomic studies in adults and manometry and dynamic radiologic studies in children [13], rectal prolapse is thought to develop as a result of circumferential intussusception of the upper rectum and rectosigmoid colon.

Predisposing conditions — The finding of rectal prolapse should be considered as a symptom of an underlying condition that predisposes to rectal prolapse [1-4,14-17]. These conditions include:

●Increased intraabdominal pressure (chronic constipation)

●Diarrheal disease

●Cystic fibrosis

●Malnutrition

●Pelvic floor weakness due to neurologic disorder or surgical intervention

In one retrospective review of 158 children with rectal prolapse managed in a resource-rich setting, prolapse was attributed to chronic constipation in 55 percent, to diarrheal disease in 7 percent, to cystic fibrosis in 3 percent, and to neurologic or anatomic conditions in 10 percent; no underlying cause was identified in 17 percent [17].

Intra-abdominal pressure — Factors that increase the intra-abdominal pressure include chronic constipation with increased straining as a major contributor [17], toilet training [12], protracted coughing (eg, pertussis, chronic lung disease), excessive vomiting, straining with urination (eg, in children with phimosis) [4] and, in rare cases, from abdominal tumors [18]. Constipation is associated with rectal prolapse in 15 to 65 percent of patients [19]. Increased intraabdominal pressure caused by forced vomiting may account in part for the association of rectal prolapse and bulimia nervosa; additional factors include diarrhea (from laxative use) and/or malnutrition [20].

Diarrheal disease — Acute or chronic diarrheal diseases caused by viruses, bacteria, or intestinal parasites can predispose to rectal prolapse [17,21-23]. (See "Shigella infection: Epidemiology, clinical manifestations, and diagnosis", section on 'Intestinal complications'.)

Intestinal parasites (eg, Ascaris lumbricoides and Trichuris trichiura) are a common cause of rectal prolapse in children, particularly in developing countries [21,24]. Rectal prolapse is a characteristic finding in individuals with trichuriasis, occurring mainly in heavily infected individuals (see "Enterobiasis (pinworm) and trichuriasis (whipworm)", section on 'Trichuriasis (whipworm)'). The development of rectal prolapse also has been reported in patients with hemolytic uremic syndrome [25,26] and malabsorption syndromes, such as celiac disease and short bowel syndrome [17,27].

Cystic fibrosis — Despite routine screening for cystic fibrosis (CF), clinical evaluation for CF is still warranted in all children who present with rectal prolapse unless there is another underlying condition that explains the prolapse. Based upon observational studies performed after routine neonatal screening in the region, approximately 2 to 3 percent of children with unknown CF status were diagnosed with CF after presenting with rectal prolapse, typically before age 5 years [17,28].

However, among children with CF, rectal prolapse is much less common than in the past, occurring in approximately 3 percent of children with CF. (See "Cystic fibrosis: Clinical manifestations and diagnosis", section on 'Rectal prolapse'.)

Malnutrition — Worldwide, malnutrition is the most common condition associated with the development of rectal prolapse. Several mechanisms are postulated [4,29]:

●Malnutrition causes hypoproteinemia, which may lead to mucosal edema and an increased potential for prolapse. Malnutrition also interferes with immune function and results in an increased susceptibility to enteric infections that cause diarrhea (see above).

●Protein-calorie deprivation can diminish the ischiorectal fat pad, thereby decreasing perirectal support.

In one controlled trial, 75 malnourished children with acute dysentery caused by shigellosis were randomly assigned to an energy-dense or control diet [30]. No differences existed between the groups in resolution of fever, dysenteric stools, or stool frequency. However, resolution of rectal prolapse was better in the treatment group (26 versus 8 percent after 5 days and 13 versus 6 percent after 10 days of dietary intervention), despite an increased frequency of vomiting in the treatment group (67 versus 41 percent).

Pelvic floor weakness — Pelvic floor weakness may occur as a result of neurologic disorders (eg, myelomeningocele, tethered cord, spinal cord injury) and surgical interventions for anorectal anomalies (eg, Hirschsprung disease or imperforate anus) [17,31]. Patients with these conditions may suffer from long-term rectal prolapse and fecal incontinence [32,33].

Other factors — Inflammatory polyps, polypoid lesions, ulcerative colitis-associated pseudopolyps, or lymphoid hyperplasia can act as lead points for rectal prolapse [17,34]. Cases of prolapse associated with neoplasms and solitary rectal ulcers also have been reported [4,34]. (See 'Complications' below.)

Other causes of rectal prolapse include Ehlers-Danlos syndrome [35], Williams syndrome [36], congenital hypothyroidism [37], anal penetration [17,38], Hirschsprung disease [39], and extensive perineal burns [40,41]. Because of the association with anal penetration, the possibility of sexual abuse must be considered in children who present with rectal prolapse [42]. If manual reduction is needed in these patients, then sedation as for other moderately painful procedures is warranted. (See "Evaluation of sexual abuse in children and adolescents" and "Procedural sedation in children: Selection of medications", section on 'Moderately or severely painful procedures'.)

Finally, behavioral and psychiatric conditions may make medical treatment of constipation or other underlying causes of rectal prolapse challenging [6].

CLINICAL MANIFESTATIONS — The presentation of rectal prolapse usually is obvious: a dark red mass with or without mucous and blood protrudes from the rectum during straining. The mass typically is detected by the parents, who bring the child urgently to medical attention [4]. As a general rule, prolapse is painless, but it can be associated with mild discomfort. A digital rectal examination may reveal decreased or absent anal tone initially, but normal tone returns within a few hours. In patients with a predisposing neurologic condition (particularly spinal lesions such as myelomeningocele), the decreased sphincter tone may persist.

The presentation of third-degree rectal prolapse (occult prolapse) is more subtle, and the diagnosis may be delayed unless a high degree of suspicion is present. The patients, usually adolescents, complain of tenesmus and anorectal pain, with the passage of blood and mucous [4].

The clinical presentation of 78 South African children with rectal prolapse was reviewed retrospectively [21]. Among those who did not have a mechanical or anatomic cause, 38 percent presented with bloody diarrhea and 36 percent with isolated rectal prolapse. Other presentations were blood per rectum with no diarrhea (17 percent), passing worms per rectum (12 percent), pain on defecation (7 percent), and vomiting (6 percent) [21].

DIAGNOSIS — The diagnosis of rectal prolapse can be made based upon the historical or physical examination findings. A painless, dark red mass at the anal verge with or without mucous is present on physical examination if the prolapse has not spontaneously reduced (picture 1).

On the other hand, if spontaneous reduction has occurred, the parents' description of such a mass that appeared during straining may suffice to make the diagnosis. Examining the child in the squatting position or asking them to strain may demonstrate the prolapse. Palpation of the prolapsed mucosa between the thumb and forefinger permits the examiner to distinguish between mucosal (Type I) or complete (Type II) rectal prolapse [4].

The diagnosis of occult rectal prolapse usually is made during sigmoidoscopy that reveals erythema and granularity of the distal rectum, or a polypoid white-topped mucosal lesion on the anterior rectal wall [43]. Alternatively, specialized imaging techniques such as fluoroscopic defecography or magnetic resonance imaging can be used to visualize the prolapse and associated pelvic floor anomalies which can guide surgical interventions [44-46].

Occult rectal prolapse may be an early finding in solitary ulcer of the rectum syndrome [43,47,48]. (See 'Complications' below.)

DIFFERENTIAL DIAGNOSIS — The following three entities must be considered in the differential diagnosis of rectal prolapse [49,50]:

●Ileocecal intussusception

●Prolapsing rectal polyp

●Rectal hemorrhoids

The child with intussusception typically appears ill and has complaints of intermittent severe abdominal pain, although some children may appear well between bouts of pain. In addition, the examiner's finger can be passed between the apex of the prolapsed bowel and the anal sphincter [4]. In contrast, in rectal prolapse, the protruding mucosa is continuous with the perianal skin (see "Intussusception in children", section on 'Clinical manifestations'). Examination of the prolapsed tissue can distinguish polyps and hemorrhoids from rectal prolapse because prolapsed polyps and hemorrhoids do not involve the entire rectal mucosa and do not have a hole in the middle.

MANAGEMENT

Approach — The management of rectal prolapse is conservative and directed toward diagnosing and treating the predisposing condition (eg, constipation, cystic fibrosis, parasitic infection). Manual reduction should be undertaken as soon as possible if spontaneous reduction does not occur [4]. If left untreated, the prolapsed rectum will be irritated by the child's undergarments, causing more bleeding; eventually, the exposed rectum will become ulcerated, congested, edematous, and more difficult to reduce.

Manual reduction — Manual reduction of rectal prolapse is performed with gloves, lubricant, gauze, and tape (figure 2). Use of sedation and analgesia may be necessary depending upon the size of the prolapse and the child's level of discomfort. (See "Procedural sedation in children: Approach".) The procedure is performed as follows:

●The child is placed prone in the knee-chest position on the examination table or the parent's lap.

●Well-lubricated gloves are used to apply gentle, but firm, persistent pressure to the prolapsed mucosa. A finger may be placed in the rectum to guide reversal of the prolapse. The prolapse should reduce in 5 to 15 minutes.

●Digital rectal examination is performed after reduction to ensure that the reduction is complete [4].

●A pressure dressing consisting of lubricant, gauze, and tape then may be applied. The buttocks may be taped together with adhesive tape for several hours if the prolapse recurs immediately after reduction [4].

●If the rectal prolapse is very large and/or difficult to reduce, application of up to one-half cup (113 g) of sugar can reduce the size of the swelling and allow for manual reduction [51].

Aftercare — Parents and patients can be taught to manually reduce the prolapse if it recurs. Patients should be sent home with a bowel regimen to treat the presumed underlying cause of the prolapse. As an example, stool softeners and increased dietary bulk are prescribed to children with constipation whereas an adjustment of pancreatic enzymes may be necessary for a child with cystic fibrosis.

For some patients, stimulant laxatives are an important part of the bowel regimen. For example, in a retrospective review of 47 children with constipation-related rectal prolapse, most of whom received simulant laxatives as part of their regimen, only three patients (6 percent) subsequently required surgical intervention [52]. Our approach is to add sennosides as the first stimulant laxative when osmotic laxatives are not sufficient to control the symptoms and escalate to bisacodyl when needed. The bowel regimen should continue until the child has regular bowel movements for several months without rectal prolapse.

During the recovery phase, providing adequate support to the buttocks and decreasing intraabdominal pressure during defecation are also important. Some authors recommend having children sit on the adult toilet (with a special seat insert to provide buttock support) or having the child use a fracture bedpan for bowel movements [4].

Surgical reduction — Surgical reduction may be necessary when prolapse recurs frequently or if manual reduction fails [4].

Emergency surgical referral is indicated if rectal prolapse cannot be manually reduced because long-term complications (eg, atonic rectal sphincter, incontinence, ulceration, bleeding, or gangrene of the bowel wall) may result [38].

Surgical correction — Multiple possible surgical interventions are used for recurrent prolapse that does not respond to nonoperative management [19,53-57]. These interventions include local therapy (eg, submucosal injections of sclerosing solutions [5,10,58-61] or anal cerclage) and surgical repair (eg, Ekehorn rectopexy, laparoscopic suture rectopexy, and posterior sagittal rectopexy) [62,63]. The choice of procedure is determined by multiple factors including the degree of prolapse, severity of symptoms, associated disorders, underlying conditions, and the treating physician's area of expertise.

Sclerotherapy is the least invasive procedure, with a success rate of up to 86 percent, and is the first choice for uncomplicated, recurrent prolapse [64-66]. Anal cerclage is uncommonly performed in children.

Surgical repair is typically reserved for patients in whom local therapy is unsuccessful [66]. Rectopexy is the most performed procedure for complicated, recurrent rectal prolapse and has an estimated success rate as high as 96 percent. In severe cases, a surgical resection of redundant rectosigmoid colon is also performed [65].

COMPLICATIONS — Local pain and self-limited mucosal bleeding are the most common complications in cases that reduce spontaneously or are manually reduced [2-4,14,49]. As mentioned above, prolonged exposure can lead to ulceration, venous obstruction, and thrombosis. In contrast to hernias, strangulation is a rare occurrence.

Solitary rectal ulcer syndrome is a rare complication of chronic rectal prolapse [67]. Solitary rectal ulcer syndrome is a benign condition usually diagnosed in adolescents who complain of rectal bleeding, pain, and passage of mucous. It may begin as an occult rectal prolapse with the above complaints and progress to the development of single or multiple localized areas of necrosis and ulceration of the mucosa, which are apparent on endoscopy [4,68]. (See "Solitary rectal ulcer syndrome".)

Inflammatory cloacogenic polyps also are associated with rectal prolapse. They are polypoid formations, usually 0.4 to 1.2 cm in diameter, that arise from the transitional zone between the columnar rectal and squamous anal epithelium and represent a regeneration process [4]. They usually present with rectal bleeding and are diagnosed endoscopically. Inflammatory cloacogenic polyps and the lesions of solitary rectal ulcer syndrome have been hypothesized to be caused by mucosal ischemia related to rectal prolapse [4,68].

PROGNOSIS — The prognosis of rectal prolapse, which depends upon the underlying etiology, usually is good. Approximately 90 percent of children who develop rectal prolapse between the age of nine months and three years respond to medical treatment and do not require surgery; recurrences rarely occur after six years of age. The remaining 10 percent of children with rectal prolapse have recurrences that persist into adulthood [4,23]. Children who present with rectal prolapse after four years of age usually have neurologic or musculoskeletal defects of the pelvis and are less likely to respond to nonoperative measures. These children warrant timely referral for surgical intervention [4,69].

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Rectal prolapse".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

●Basics topic (see "Patient education: Rectal prolapse in children (The Basics)")

SUMMARY AND RECOMMENDATIONS

●Definition – Rectal prolapse refers to the extrusion of some or all of the rectal mucosa through the external anal sphincter (figure 1). (See 'Types' above.)

●Predisposing conditions – The finding of rectal prolapse should be considered as a symptom of an underlying condition including increased intraabdominal pressure, diarrheal disease, cystic fibrosis, malnutrition, pelvic floor weakness, polyps, intestinal lymphoid hyperplasia, intestinal neoplasm, and sexual abuse. (See 'Predisposing conditions' above.)

●Clinical manifestations and diagnosis – Rectal prolapse is usually diagnosed at presentation by the presence of a dark red mass with or without mucous and blood protruding from the rectum during straining (picture 1). (See 'Clinical manifestations' above and 'Diagnosis' above.)

●Differential diagnosis – Important conditions that can mimic rectal prolapse include (see 'Differential diagnosis' above):

•Intussusception – The child with intussusception typically appears ill and has complaints of intermittent severe abdominal pain; unlike patients with rectal prolapse, the examiner’s finger can be passed between the apex of the prolapsed bowel and the anal sphincter.

•Prolapsed rectal polyp or rectal hemorrhoid – These conditions do not involve the entire rectal mucosa and do not have a hole in the middle.

●Management – Management consists of manual reduction as soon as possible if spontaneous reduction does not occur (figure 2) (see 'Manual reduction' above).

Emergency surgical referral is indicated if rectal prolapse cannot be manually reduced because long-term complications (eg, atonic rectal sphincter, incontinence, ulceration, bleeding, or gangrene of the bowel wall) may result. (See 'Surgical reduction' above.)

Once the rectal prolapse is reduced, patients require a bowel regimen to treat the presumed underlying cause of the prolapse such as increased fiber diet, stool softeners, and simulant laxatives in children with constipation or pancreatic enzyme supplementation in children with cystic fibrosis. (See 'Management' above and 'Manual reduction' above.)

Patients with recurrences of rectal prolapse despite appropriate nonoperative therapy warrant referral for surgical correction. (See 'Surgical correction' above.)

ACKNOWLEDGMENTS — The UpToDate editorial staff acknowledges Rana Kronfol, MD, who contributed to an earlier version of this topic review.