Gastroenterologist Tim Buie provides insights on resolving the vicious cycle of chronic constipation and rectal prolapse
“Our 24-year-old son is severely affected by autism. I’m writing about his rectal prolapse, which we understand is associated with his chronic constipation. His doctor recommends surgery. But first I want to understand this more from someone who has experience working with patients who have autism. I greatly appreciate any information you can share.”
This week’s “Got Questions?” answer is by pediatric gastroenterologist Timothy Buie. Dr. Buie is the director of gastrointestinal and nutritional services at Massachusetts General Hospital’s Lurie Center for Autism, a member of the Autism Speaks Autism Treatment Network (ATN).
Editor’s note: The following information is not meant to diagnose or treat and should not take the place of personal consultation, as appropriate, with a qualified healthcare professional and/or behavioral therapist.
Thank you for your question. While surgery may be the right course for your son, I believe you are correct to want to understand the causes of his prolapse before making a decision.
For readers who may not be familiar, rectal prolapse is a condition where a portion of the rectum – the final section of the large intestine – telescopes down into the anal canal, sometimes even out of the anus.
Among adults – even young adults such as your son – prolapse typically results from years of chronic constipation and its associated straining during bowel movements. As many readers of this advice column know well, chronic constipation is particularly common among both children and adults affected by autism.
Also see Dr. Buie's Office Hours video and Q&A series.
However, it’s relatively unusual for rectal prolapse to occur in young children – even children with autism and chronic constipation.
When I see rectal prolapse in young children, I carefully screen for conditions that can cause malabsorption of nutrients. These conditions include cystic fibrosis and celiac disease. Prolapse can also result from certain parasitic intestinal infections. There are straightforward screening tests for all these conditions.
Consider the history
Still, whatever the age of the patient with rectal prolapse, it’s important to take a careful history. Did your son’s rectal prolapse develop progressively with constipation? That is, did it get gradually worse and worse over months and years?
Unfortunately, this classic scenario can set up a vicious cycle: The prolapse progresses to the point where it makes it harder for the person to make a bowel movement. So the constipation gets worse, too. This most frequently occurs when the prolapse is internal and creates a partial blockage. This blockage can produce the feeling that one needs to pass a bowel movement.
I have had several patients with autism with just this situation. Sometimes they try to reduce the feeling of blockage by inserting a finger into the rectum to push the prolapsed rectum out of the way. This allows the stool to pass, but caregivers often misinterpret the behavior as “playing with stool.” This is particularly the case with nonverbal or minimally verbal children and adults because they have difficulty explaining their discomfort and what they’re doing.
Once other medical causes for the prolapse have been ruled out, management typically starts with relieving the constipation – or bowel regulation. The goal is to get the stool soft and maintain a very regular schedule of bowel movements.
Working with your son’s doctor, I recommend using a stool softener such as aloe juice, a magnesium laxative or lactulose. If those don’t work, I would consider PEG-3350. Sometimes it’s helpful to add an over-the-counter bowel stimulant such as senna or bisacodyl to prompt bowel contractions.
I recommend working toward a daily schedule of one or two bowel movements a day to assure that things are clearing easily. This can significantly reduce the rectal pressure that causes the prolapse.
Also see the Autism Speaks ATN/AIR-P Guide for Managing Constipation in Children, available for free download.
Re-learning how to “push”
In addition, it can help to relearn how to make a bowel movement with less pressure on the rectum. Most of us bear down, or squeeze, at the rectum during a bowel movement. But we want to avoid that to lessen a rectal prolapse.
We’ve had success by coaching patients to tighten their core belly muscles – “as if you were blowing up a balloon” – but without squeezing the rectum. If possible, I highly recommend getting the help of a physical therapist that is experienced dealing with stool incontinence issues. Clinics that specialize in autism – such as those in the Autism Speaks ATN – are a good place to look for such expertise.
Find the ATN center nearest you here.
Even with regulation of the bowels, it may take a long time for the prolapse to resolve completely. But chances are good that it will reduce significantly once your son can pass stool without straining.
When bowel regulation isn’t enough
Sometimes, bowel regulation isn’t enough to reduce rectal prolapse. In these cases, I recommend further evaluation, as follows:
Some individuals with chronic prolapse have what we call an internal “lead point” that pulls the rectum downward when stool passes through. A gastroenterologist can investigate this possibility with sigmoidoscopy. In this routine outpatient procedure, the doctor examines the inside of the rectum and lower part of the colon using a flexible tube with a camera.
During the sigmoidoscopy, the doctor should also see whether the prolapse has caused ulceration or other damage to the inner wall of the rectum. Such damage can add to swelling and further the blockage. Treatment for a solitary ulcer includes softening the stool, but may also require medication to promote healing.
At times, constipation and straining can be the result of pelvic floor muscle function problems. A gastroenterologist can investigate this possibility by testing of the pressure produced by the anus, or rectal sphincter (rectal manometry). If the sphincter pressure is abnormal, treatment strategies such as training through biofeedback or physical therapy can work well for kids who are able to follow the associated directions. For children with intellectual disability, a program of regular sitting on the toilet with behavioral prompts tend to be more successful when done in combination with stool softening.
Also see the Autism Speaks ATN/AIR-P Parent’s Guide to Toilet Training, available for free download.
When it’s time for surgery
Lastly, there are times when rectal prolapse fails to respond to any of these behavioral or medical approaches. The good news is that there are several surgical approaches that can help. I strongly recommend consulting with an experienced gastroenterologist who can evaluate which type of surgical intervention is best for your son.
One option involves injecting a solution into the wall of the rectum to temporarily stiffen the rectal wall and hopefully ease the passing of stool.
Another approach involves surgically tacking the bowel higher in the abdomen to prevent its lower section dropping down into the rectum. This has helped some individuals. But prolapse recurs in many others who continue to strain with bowel movements. So this option should be done in combination with a rigorous plan to soften stools and avoid constipation and straining after surgery.
Difficult problems with prolapse require close medical management by a knowledgeable and experienced gastroenterologist and/or surgeon, who can help you consider all these strategies based on your son’s needs.
I hope this has proved helpful. Please let us know how you and your son are doing by sending us another email to GotQuestions@AutismSpeaks.org.