Food Allergy Living Blog Tagged Results

We’ve talked about Short Bowel Syndrome (SBS) in previous posts. Our last post on SBS talked about how the small intestine is the absorption hub on the GI tract. When part of the small intestine is removed, you lose that important area for water and nutrient absorption and your body is no longer able to utilize the food and liquid that you consume. For this reason, total parental nutrition (TPN) may be necessary at first. Remember that TPN is nutrition that is delivered straight into the blood stream, rather than going through the digestive tract. The digestion and absorption processes are skipped.

Although this can sustain someone, there are many risks associated with TPN and in order for the remaining portion of the small intestine to adapt, it is very important to start enteral nutrition (EN) as soon as possible. Recall that EN is where nutrition is delivered through the digestive tract, either through a feeding tube or by eating regularly. So what exactly does it mean for the small intestine to adapt? We’ll focus on this subject in today’s blog post!

What is intestinal adaptation?

After a significant portion of the small intestine is removed, the remaining small intestine goes through a process of adaptation that increases its ability to absorb water and nutrients. What changes are involved in adaptation?

• The remaining portion of the small intestine may grow slightly in length
• The remaining portion of the small intestine may grow in diameter (width)
• The inner lining of the small intestine grows, increasing in surface area and the ability to absorb

The growth of the inner lining and absorptive capacity is perhaps the most important feature. How does the growth of the inner lining improve the ability to absorb nutrients? Think about a sponge, which we use to absorb liquid. The reason that it absorbs so well is the nooks and crannies which give the sponge a large surface area. Think about a 2 by 2 inch sponge in comparison to a 2 by 2 inch wood block. The sponge will absorb much more due to the high surface area. The growth of the inner lining of the intestine increases the surface area to form nooks and crannies so that it can absorb efficiently, like a sponge.

The prognosis of a patient with SBS depends on how well their gut adapts. If the remaining portion adapts enough, it will be able to compensate for the lost portion of the intestine. Once this happens, TPN can be stopped because the digestive tract is now able to absorb enough nutrients and water from the diet.

Can you support the adaptation process or speed it up?

Intestinal adaptation can take up to 2 years to occur. The best way to support gut adaptation is to eat! Consuming some foods by mouth or through a feeding tube triggers the release of certain hormones and promotes blood flow to the GI tract. The hormones and blood flow promote the adaptation process. This is why it’s so important to start enteral nutrition as soon as possible. TPN continues to deliver the bulk of nutrients that the patient needs to live and be healthy, so the food in the digestive tract is not expected to fulfill this role yet. But little by little, the patient is able to tolerate more foods through the GI tract and able to absorb more and more nutrients until eventually, their gut has adapted enough to allow them to stop the TPN. Check out our previous post on how Neocate can help children with SBS wean off of TPN sooner.

Researchers are studying ways to help the gut adapt quicker and function better. You can check out some of the research being done on SBS online at clinicaltrials.gov.

To view a true story about a little girl with SBS who is in the adaptation process, check out this video, Elizabeth's story,fromJohns Hopkin's Children's Center.

I hope this post helps you to better understand SBS and how gut adaptation works. If you have any personal experiences, please share them with us!

-Mallory

As we’ve discussed in previous posts, short bowel syndrome (SBS) is a malabsorption syndrome that occurs in patients who have had a significant portion of their small intestine removed. In this post, I will explain a little more about how nutrient absorption works and why malabsorption is a problem for patients with SBS.

What exactly is Malabsorption?

Malabsorption is a difficulty in absorbing nutrients from food. There are 2 requirements for proper nutrition: 1) you must consume nutrients from food, supplements, formula etc. and 2) your body must absorb these nutrients from the digestive tract so that it can be used throughout the body. Without absorption, your body is not able to access any of the nutrients found in food that you consume.

The Small Intestine: The Absorption Hub of the Digestive Tract

The small intestine absorbs about 90 percent of the nutrients and fluids your body needs to function.Although it is smaller in width compared to the large intestine (hence the name small intestine), it is actually the longest portion of the digestive tract and composed of three sections: the duodenum, the jejunum and the ileum.

So what makes the small intestine so good at absorbing nutrients? The answer is its high quantity of surface area. Believe it or not, the small intestine has the surface area of a tennis court! The lining of the small intestine (known as the epithelium) is not flat; it has folds of skin called “mucosal folds”. It also has villi, which are small finger-like projections and microvilla, which are tiny, hair-like structures. The combination of these 3 features results in the small intestine’s vast quantity of surface area and its ability to absorb nutrients so well.

Short Bowel Syndrome, Intestinal Adaptation and Nutritional Stability

Since the small intestine is so important for nutrient absorption, removal of even a small portion can cause malabsorption, such is the case with SBS. The severity of malabsorption depends on how much and which portion of the small intestine was removed. There are two main goals in treating a patient with SBS:

• Intestinal Adaptation: The hope is that over time, the remaining small intestine will adapt by growing longer and increasing its ability to absorb nutrients. With successful adaptation, the patient will eventually be able to digest and absorb foods normally.
• Nutritional Stability: During this adaptation period (which may take years), amino acid-based formulas, such as Neocate, are used to provide nutritional stability. Because the nutrients in Neocate are in their simplest form, they are easiest to digest and absorb. Neocate provides all the necessary nutrients required for a child’s growth and development to support health and wellness until the small intestine adapts and begins to function properly. (Interestingly, children with SBS are more prone to food allergies which is another reason why Neocate may be used with children who have SBS).

Hopefully this explanation helps you to understand the underlying problem with SBS and how an elemental formula such as Neocate is used to manage SBS. Do any of your children have SBS? What has been your experience with adaptation and nutritional stability?

-Mallory