Rectal prolapse overview

# Overview
Rectal prolapse is when the tissue that lines the rectum falls down into or sticks through the anal opening. It starts from rectal intussusception, followed by external mucosal prolapse, and eventually a full protrusion of all layers of the rectum. Rectal prolapse occurs more frequently in the elderly and women and most common symptoms include pain, fullness or a lump inside rectum, fecal incontinence, constipation and bloody and/or mucous rectal discharge. Common causes of rectal prolapse include rectal denervation, perineal nerve injury, kinking of the redundant loop of sigmoid colon and altered colonic motility. Rectal prolapse must be differentiated from hemorrhoids, anal fissure and perianal abscess, anal cancer and condylomata acuminata. Rectal prolapse cannot be corrected nonoperatively. It has two different surgery approaches: abdominal surgery (lower recurrence rate and better functional outcomes) or perineal surgery (in elderly patients, significant comorbidities, high risk patients for general anesthesia, previous pelvic surgery or radiation).

# Historical Perspective
In medieval times, scientists suggested that rectal prolapse could be prevented by using a scar (through burning the anus) or by using a stick. In the 20th century, rectal prolapse was studied scientifically and Nowadays there are various surgical methods for rectal prolapse treatment.

# Classification
Rectal prolapse may be classified into complete and incomplete subtypes based on disease extension or be classified into pediatric and adult subtypes based on age of presentation. Also, it may be classified by disease grading.

# Pathophysiology
Rectal prolapse starts from rectal intussusception, followed by external mucosal prolapse, and eventually a full protrusion of all layers of the rectum. Rectal prolapse is associated with several coexisting anatomic abnormalities including diastasis of the levator ani, abnormally deep cul-de-sac and redundant sigmoid colon.

# Causes
Common causes of rectal prolapse include rectal denervation, perineal nerve injury, kinking of the redundant loop of sigmoid colon, loss of rectal compliance and altered colonic motility.

# Differentiating Rectal prolapse overview from Other Diseases
Rectal prolapse must be differentiated from other diseases that cause anal discomfort such as hemorrhoids, anal fissure and perianal abscess, anal cancer and condylomata acuminata.

# Epidemiology and Demographics
The prevalence of rectal prolapse is relatively low. It occurs more frequently in the elderly and women.

# Risk Factors
Common risk factors in the development of rectal prolapse include advanced age, female gender, obstetric history, hormonal status and long term increased intra-abdominal pressure.

# Natural History, Complications, and Prognosis

## Natural History
Hemorrhage occurs frequently if the prolapsed rectum is left unreduced. If rectal prolapse is persistent for a long time, urological impairments may be associated.

## Complications
Common complications of rectal prolapse include fecal incontinence, constipation and rectal incarceration or even strangulation.

## Prognosis
All women with prolapse can be treated and their symptoms improved, even if not completely resolved.

# Diagnosis

## History and Symptoms
Most common symptoms of rectal prolapse include pain, fullness or a lump inside rectum, fecal incontinence, constipation and bloody and/or mucous rectal discharge.

## Physical Examination
Patients with rectal prolapse usually have rectal mass, skin excoriation or irritation of anus in physical examination.

## Laboratory Findings
There are no diagnostic lab findings associated with rectal prolapse.

## Imaging Findings
- Based on the radiological characteristics, rectal prolapse may be graded as internal rectal prolapse (recto-rectal intussusception and recto-anal intussusception) or external rectal prolapse (exteriorized rectal prolapse).
- Dynamic pelvic MRI can evaluate pelvic floor anatomy, dynamic motion and rectal evacuation.
- Demonstration of anal sphincter defect by 3D-endoanal ultrasonography is helpful for sphincter reconstruction.

## Other Diagnostic Studies
In rectal prolapse, fluoroscopic defecography, MRI defecography, or balloon expulsion testing may be helpful for diagnosis. Pre-operatively, all patients should undergo anoscopy and colonoscopy.

# Treatment

## Medical Therapy
Rectal prolapse cannot be corrected nonoperatively, although some of the symptoms associated with this condition can be reduced medically. Nonoperative treatments of rectal prolapse such as medications reducing edema, correction of constipation, exercises straining the perineum are helpful.

## Surgery
Rectal prolapse surgery has two different approaches: Abdominal surgery (lower recurrence rate and better functional outcomes) or perineal surgery (in elderly patients, significant comorbidities, high risk patients for general anesthesia, previous pelvic surgery or radiation).

## Prevention
- Primary prevention: Constipation is one of the most common cause of rectal prolapse. Sufficient fiber intake and pharmacological treatment of constipation (laxatives) can prevent developing rectal prolapse
- Secondary prevention: Ultimate goal of treatment is to prevent progression of prolapse to incarceration or strangulation and to restore defecation function.