Rectal prolapse is when the mucosal layer, or full thickness layer of the rectal tissue, protrudes through the anus. It is often used to describe complete rectal prolapse when in actual sense, it is comprised of three different entities including internal prolapse, mucosal prolapse and full thickness prolapse.
The most common presenting complain is a mass protruding from the anus. At first, the mass protrudes only after defecation and it retracts spontaneously. As the disease progresses, it protrudes more often and even during normal daily activities like walking. Eventually there is a full prolapse that may require manual reduction. Sometimes, replacement becomes impossible due to incarceration of the prolapse but this is rare. Some patients may also complain of pain. Other presenting features are prolapse of other pelvic organs, constipation and fecal incontinence .
Physical examination will reveal decreased sphincter tone, protruding anal mucosa, thick concentric mucosal rings and sulcus between the rectum and anal canal.
With appropriate treatment, the prognosis is usually favorable. 90% of pediatric patients do well on conservative management. Post-surgical mortality is also very low but there may be complications like bleeding and dehiscence at the op site as well as mucosal ulceration and necrosis of the rectal wall. Recurrence rate ranges from 0% to 50% depending on the type of corrective procedure employed .
Even though the cause of this condition remains unclear, over half of the cases have been found to be associated with constipation and chronic straining on defecation. Other factors that may contribute to the development of this condition include previous anal surgery, pregnancy, diarrhea, chronic obstructive pulmonary disease, and benign prostatic hypertrophy. Others are pertussis, parasitic infections like schistosomiasis, neurologic disorder from previous pelvic trauma or spinal tumors and disordered defecation.
Some anatomic features that are present in some patients like patulous anal sphincter, levator diastasis, redundant sigmoid, posterior rectal fixation with a long mesentery and deep anterior Douglas cul-de-sac have been found during surgery for this condition. Whether these features are predisposing factors or results of the condition remains unclear .
Cases of rectal prolapse remain highly unreported and as such, the true incidence is unknown. It has a bimodal peak age of occurrence, occurring mostly in the 4th and 7th decades of life. It is primarily a disease of women as up to 80% of affected individuals are female and it occurs together with prolapse of some other organs, like uterus, and pelvic floor descent.
Pediatric patients can also be affected, most commonly in the first year of life. In pediatric age group, the incidence is distributed evenly among both sexes .
The following may help reduce chances of getting rectal prolapse: avoiding constipation by eating high fiber diet and staying hydrated, Kegel exercises to improve pelvic floor muscles and avoid delaying the urge to defecate .
Rectal prolapse is most commonly a disease of the elderly, especially elderly women. It presents with a wide array of symptoms although it could be asymptomatic in many cases .