What is Congenital Sucrase-Isomaltase Deficiency (CSID)?
I attended a three day GI conference at the University of Michigan in September. It was an amazing conference packed full of presentations from some of the best GI doctors and dietitians. One presentation was on a topic I had never heard of, so I was intrigued and ready to learn more about it.
Congenital Sucrase-Isomaltase Deficiency (CSID) is a rare disorder that causes individuals the inability to digest certain sugars due to an absence or low levels of two digestive enzymes, sucrase and isomaltase. Both of these enzymes are involved in the digestion of sugar and starch. Table sugar is broken down into glucose and fructose with the help of the sucrase enzyme. Isomaltase is one of the several enzymes that help digest starches.
Both sucrose (found in fruits, and known as table sugar) and maltose (sugar found in grains) are disaccharides, which means they are made of two simple sugars. During digestion, intestinal enzymes break these down into simple sugars called monosaccharides. Sucrose=glucose + fructose and maltose=glucose + glucose. An individual with CSID has difficulty breaking down the disaccharides into monosaccharides that the body uses for fuel. These disaccharides are too large to be absorbed in the intestines by the microvilli (known as the brush border).
Starch can be a simple or complex carbohydrate. Simple carbohydrates have one or two sugar molecules, and complex carbohydrates have three or more sugars linked together.
Multiple enzymes are needed to properly digest starch. Digestion begins in the mouth with an enzyme in the saliva called amylase. Digestion continues in the stomach by further breaking down the food. In the small intestine, starch is processed by an enzyme called pancreatic amylase and converted into maltose and sucrose. The brush border contains numerous enzymes (sucrase, lactase, maltase) to continue the breakdown of digested food into smaller particles that can be better absorbed. The isomaltase enzyme breaks the bonds linking sugars into glucose, which can’t be broken down by amylase or maltase. This is one of the final steps in the digestion of starch to glucose.
To sum it up, those with CSID lack the sucrase and isomaltase enzymes to properly break down the food to a simpler form, so the body can absorb it.
Without the proper enzymes, digestion can’t take place correctly and individuals can have symptoms, such as:
So, what do you do if you suspect you have CSID?
Visit sucroseintolerance.com to take their quiz. On that site there is also an “ask your doctor” form to take to your physician. A sucrose breath test can help with the diagnosis. This can be ordered by your doctor or I can order a complimentary sucrose breath test to be sent to your home.
What if you have a positive breath test?
You will do a two-week elimination diet of sucrose and starch, followed by a gradual reintroduction of both. The reintroduction will help identify how much of these foods you can tolerate. Many like the guidance of a dietitian familiar with this deficiency to help them navigate through the elimination and reintroduction phases. Others also do the diet along with a test of the sucrase enzyme, Sucraid® (sacrosidase) Oral Solution. The sucrase enzyme can be purchased through One Patient Services, a subsidiary of QOL, Medical, LLC, the manufacturer of Sucraid® Oral Solution, at SucraidASSIST.com.
Please consult with your doctor regarding your symptoms and for a final diagnosis.
If you have any questions regarding Congenital Sucrase-Isomaltase Deficiency, please feel free to call or text me at 410-963-4782 or email at [email protected].
Registered Dietitian Nutritionist - CDN, RDN
My name is Valerie Polley. I am a Indianapolis-based registered dietitian and owner of Blue Tree Nutrition. I consult with clients both local and far away.
I have a bachelor’s degree in nutrition from Purdue University and I have been practicing for 20 years.
I thoroughly enjoy helping clients through their gut health journey. I see a range of GI issues including, but not limited to celiac disease, IBS and SIBO. I also specialize in the FODMAP elimination diet.
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I have suffered with an unhealthy gut for years and much likely due to my bad eating habits, I’m slowing improving. Y food choices but get discouraged easily when I can’t pinpoint the cause of my problems. Reading your article makes me think I have CSID. Can I do the complimentary hydrogen test? Thank you
There can be many reasons for gastrointestinal issues. I will email you at [email protected] so we can talk more about it.
I had an endoscopy last Sept. It said CSID. I haven’t really received much more help to live with this beast. I’m on the toilet more than I’m not. I weigh 92 lbs and sad at my body appearance. Saw Rochester Mayo Dr and he is making me take the breath test AND a fructose test too whenever they get in touch with me, because he thinks the biopsy was wrong last Sept. I’m a true mess. I know I do have Sucraid and it seems to help some, if I remember to take it.
I am sorry you are dealing with this. I see clients with varying degrees of SID. Some have SID with other things on top, such as IBS. Once you get the results of the breath tests, then you can go from there. There are dietitians that can help and I am happy to help as well depending on what state you live in. I would try to use the Sucraid now to see if it gets control of some of your symptoms. You are welcome to reach out to me at [email protected] or 410-963-4782.
Does anyone know of any CSID cookbooks?
I have never been asked this question, so I did some searching. I found one on Amazon called A Place to Start Without Sugar and Starch. It is for those with CSID. That is the only cookbook I found. Pinterest has some ideas as well. This looks like something that is lacking, but could be very helpful as more individuals are diagnosed with it.
My 13 year old daughter was diagnosed last July with CSID and lactase deficiency. She is on sucraid and lactaid. She lost 20 pounds the first few weeks when cutting many sugars and saw improvement. Now she’s back to cramping, bloating. Where can I find directions on how to do the 2 week elimination diet? Any help will.be appreciated. She is very frustrated and sad about her condition.
I am sorry your daughter is dealing with this. I know it can’t be easy for any of you. I am not sure what you mean by the 2 week elimination diet. Is that for SID or something else? Some individuals with SID also deal with other issues, such as IBS. I would need to evaluate what she is eating now and go from there. I am happy to help out or find another dietitian closer to you. You can reach out to me at [email protected] or 410-963-4782.