Gastrointestinal Issues, Part 2

Down Syndrome Center at UPMC Children’s Hospital of Pittsburgh

Arvind Srinath, MD, discusses issues related to constipation. It’s the second of a three part series about gastrointestinal issues that impact children with Down syndrome.

Released: 4/15/13


Dr. Vellody: Hello everyone and welcome back for another Down Syndrome Center podcast. As always, I am your host, Dr. Kishore Vellody. Today, we are joined again by Dr. Arvind Srinath who is a pediatric gastroenterologist here at Children’s Hospital of Pittsburgh of UPMC. Today, Dr. Srinath is going to be discussing issues related to constipation in Down syndrome. Hey Arvind, thanks again for being with us!

Dr. Srinath: Absolutely, thank you for inviting for this presentation. I really appreciate this opportunity.

Dr. Vellody: No problem, it’s a pleasure having you on board with us again. Well, let’s get right into this podcast, shall we? Can you give us your definition of constipation?

Dr. Srinath: There’s no uniform definition for constipation. It’s truly dependent on what a physician can glean on historical and physical findings. The factors that we consider are the stool frequency, size and consistency, how easy it is to pass a stool, the presence or absence of soiling (or unintentional stooling in the underwear), stool withholding behavior, and, on exam, the presence of hard stool when they do a rectal exam or a stool mass felt when they do a belly exam.

Dr. Vellody: Okay, thanks for that definition. But now let me give you a common case that we see in clinic and get your opinion. Let’s say there is a young, breastfed infant who is passing soft stools with no pain or straining every 3-4 days. Would that be constipation by your definition?

Dr. Srinath: So, that’s a great point. I think it’s really good to use an example in this case because its such a difficult diagnosis to make. First of all, I will say that frequency is one of the considerations we have when diagnosing or not diagnosing constipation. If an infant is stooling every 3 or 4 days, and the stools are soft, then I wouldn’t say that they’re constipated. If they’re stooling ever 3 to 4 days or even if they’re stooling every day and they’re having hard, pellet-like stools or even a sign of a fissure or a tear when they’re passing a stool, then I would say that they are constipated. The last thing I will bring up is the frequency of stooling changes with age. Some normal breastfed babies might not have a bowel movement for weeks.

Dr. Vellody: Well, I can tell you from experience as a parent that it certainly does take a lot of patience from a parent to wait that long for a baby to have a bowel movement. But let me give you one other brief scenario. What about a young infant who seems to struggle to stool but then passes a normal soft stool after all that apparent difficulty. Is that constipation?

Dr. Srinath: There is a condition where infants are still in the process of developing and they quite frankly can’t tell what to tighten and what to relax when they’re pooping. It appears that they’re struggling and really working hard to poop and then they have a normal bowel movement. This is a condition that is not constipation, will actually get better with time, and is nothing to really worry about. It’s just a developmental milestone, so to speak.

Dr. Vellody: Thanks for that explanation. Let me give you another scenario. We have many children who come in with what the parents say is normal stooling. However, what we discover is that the child is actually stooling 2-3 times per day, and the stools are often hard and painful when they come out. Because the child is technically stooling every day, the parents often don’t feel this is constipation. What do you think?

Dr. Srinath: If someone is having a poop for instance 3-4 times a day, and it is hard and they’re straining and they’re struggling, then despite the frequency which might seem like a decent amount within a day, I would still classify that as constipation. On the other hand, if someone is having a normal, soft bowel movement in the absence of straining, hard stools, or any tearing that occurs once every week, then that person isn’t constipated. That can be along the normal spectrum for that person.

Dr. Vellody: Great, thanks for clarifying that point. So, now that we know a little bit more about what constipation is, tell us how common it is in kids in general?

Dr. Srinath: Absolutely. Rates of constipation are up to 30 percent in the general population. They account for up to 5 percent of visits to the general pediatrician. Because we’re a subspecialty clinic they account for about 10-25 percent of visits to a pediatric gastroenterologist. With regards to what ages they usually occur, constipation usually peaks between the ages of one and four years. It’s major sequelae of soiling usually peaks between the ages of four and seven when kids are too busy to want to sit on the toilet. 95 percent of constipation in children is what I call functional nature, meaning there is no underlying medical problem leading to it. This will get better with time.

Dr. Vellody: Thanks, Arvind. You know, you just mentioned something that a lot of our listeners may not be too familiar with. You were talking about soiling, but in a child who is constipated. So, can you give us a little more of an example of what you mean by having the ability to both have loose stools and be constipated at the same time?

Dr. Srinath: That’s an excellent point. I appreciate the clarification. To go back, I think it’s worthwhile just briefly covering the normal physiology behind stooling. When stool is in the bottom of the large intestine (or the rectum), one can feel it. There is that certain sensation of fullness there. That sensation is felt in the brain and you decide whether or not you want to relax and push it out when it is a convenient time. If its inconvenient, you have the power to hold it in and wait for a more convenient time to let it out. The one issue is, the longer the stool stays in the gut, the more water is absorbed from it. It becomes harder and harder. The longer you wait, it’s harder to poop that little ball out. In some kids, especially in the toddler and older age range, who naturally would rather play or do something else other than sit on the toilet, this withholding behavior can lead to a pretty hard, large ball of stool in the last part of their gut (or rectum). This stool can effectively be difficult to poop out, then painful to poop out, which leads to a huge cycle of withholding even more and having the stool above it just accumulate. When the stool above it accumulates, there’s only two ways it can go – either out around the ball below it or up back where it came from. Going back up is not an option. What ends up happening is there is overflow of liquid stool around that hard ball leading to the unintentional passage of stool that it is liquid into the underwear.

Dr. Vellody: All right, well thanks for explaining that to us. You know, we know that constipation is very common in Down syndrome. Does anyone really know why that is the case?

Dr. Srinath: That’s a really good point. As I’ve touched upon in our previous podcast, it has been postulated that the nerves that control the movement of the gut are somewhat dysfunctional in patients with Down syndrome. This can lead to the slow movement of contents through the gut and potentially to the symptom of constipation. Why this happens is a little bit unclear. It may be a problem of the development of these nerves while the baby is in the womb. Other potential causes for constipation in patients with Down syndrome include hypothyroidism and an entity called Hirschsprung disease which I’ll touch upon in a little bit.

Dr. Vellody: Perfect. So now that we know how common constipation is and that it is more common in kids with Down syndrome, what can we do about it?

Dr. Srinath: That’s a great question. Americans spend over 400 million dollars per year in laxatives. So as a society we’re willing to spend an enormous of money to move our bowels. Treatment is not necessarily medications alone. Dietary changes that can be made can include increasing the fluid intake. In infants greater than the age of 6 months, you might consider prune or pear juice in small amounts and fruits and vegetables. Lifestyle changes can include adhering to what I call a stooling schedule or sitting on a toilet on a regular basis to sort of retrain the gut to evacuate on a regular basis. This can help restore order to the system. Other potential ways to treat constipation include medications. These can be stool softeners, lubricants, or even stimulants. An example of a stool softener is Miralax or polyethylene glycol. This works by drawing water into the gut and effectively making it easier for the body to flush the stool out. Lubricants can include mineral oil which, as their name suggests, helps facilitate the stool moving through the gut. Lastly, stimulants, examples include Senekot and Ex-Lax, cause the gut to contract and therefore facilitate expulsion of the stool.

Dr. Vellody: Thanks for that comprehensive look at the treatment options for constipation. But before we get too much further, I’d like to bring up a concern that has been circulating on the internet specifically about Miralax. There was an article in a newspaper that discussed that Miralax has not been tested in children, and it raised concerns about using it in children. What are your thoughts on this?

Dr. Srinath: Miralax and all these medications in general are just used as adjuncts to help children with constipation get better. What’s really going to help them get better is the dietary and lifestyle changes that I mentioned earlier. Hence, there’s probably not a good need to use Miralax long term if the right habits from a dietary and lifestyle standpoint can be treated.

Dr. Vellody: I couldn’t agree with you more. And it would be great if it was easy to get kids to change their dietary and lifestyle habits, but sometimes it is hard to get that done, especially with the kids that I follow at the center. Some of the kids just get set in their ways, so to say, and it makes it almost impossible to make those changes. In those cases, we have to make a judgment call regarding keeping them on a medication or having them struggle with their constipation. I’m personally not sure about whether there’s anything different about the Miralax versus any other medication in terms of how well they’ve been studied in children. That said, as soon as a child doesn’t need medication anymore for whatever reason, including constipation, we take them off of those medications as soon as possible. Well, all right, we’re getting close to the end of this podcast. Before we close, let me ask you this question. When should a pediatrician or family practitioner refer a child to the GI clinic for something like constipation?

Dr. Srinath: Excellent question. What I’d like to get at is what are the warning signs that something else is going on in those 5 percent of people with constipation that might not be attributed to just normal gut function. 2 potential causes for this include hypothyroidism and an entity called Hirschsprung disease which are relatively more common in children with Down syndrome and can lead to symptoms of constipation. Signs of these conditions do warrant consideration for a referral to a subspecialist. Some of these symptoms can include difficulty passing stool in the newborn period, distention or bloating, vomiting that’s green, poor growth, intermittent episodes of fever or bloody diarrhea, lethargy, or just generalized swelling. Hirschsprung disease which is more common in patients with Down syndrome, roughly occurring in 2-10 percent in patients with Down syndrome compared to 1/5000 to 1/10,000 in the general population, is a condition where there is an absence of nerves usually in the most distal part of the gut which paradoxically creates a permanently contracted area that prevents stool from being expelled. It needs to be treated to prevent more complications. Hence, the need for a referral.

Dr. Vellody: Excellent. Thanks for that summary. Can you tell us, is it possible for any of these conditions to show up later in life or do they always show up in the newborn period?

Dr. Srinath: Absolutely. Hypothyroidism can occur any time in children with Down syndrome, not necessarily in the newborn or infant period. Similarly, although Hirschsprung disease most commonly presents in the first couple months or years of life, it can go undetected. Or, due to the varying degrees of its involvement, not present until later on in life. Given it’s higher rate in patients with Down syndrome, one must always consider it when treating constipation.

Dr. Vellody: Thanks. I know we always have to keep those possibilities in mind for the kids that we follow with constipation at the Center. Well, Arvind, that wraps up the time we have for today’s podcast. Thanks so much for being here again with us today.

Dr. Srinath: It was my pleasure. Thank you again for this opportunity. I look forward to the next time.

Dr. Vellody: Well, we’ll look forward to having you join us for at least one more podcast. Until next time, we’ll keep on the lookout for any listener related questions that could be sent to Bye bye for now.

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