How to Order
Important Safety Information
Prescribing Information
Healthcare Provider Site

Understanding the genetics of Congenital Sucrase-Isomaltase Deficiency

All individuals inherit two copies of most genes in their DNA. You inherit one set of genes from your mother (maternal genes) and one set from your father (paternal genes). Each gene is a code or set of instructions that your body’s cells follow to make proteins, including enzymes. These proteins and enzymes determine how your cells and tissues grow, develop, and function.

Try Sucraid® 
4-Day Trial

If you have been diagnosed with CSID, ask your GI doctor if Sucraid® is right for you.

Try Sucraid®

Sometimes a gene’s 
code is altered.

Genes that have been altered are called variants. Most human genes contain many naturally-occurring gene variants.

A gene variant may alter how a cell makes the protein or enzyme that is coded by that particular gene. Most gene variants are benign, which means they do not cause an alteration in the function of the protein or enzyme. Sometimes, the gene variant results in an altered protein or enzyme that doesn’t function normally. These variants are considered pathogenic when the dysfunctional protein causes a disease.

Congenital Sucrase-Isomaltase Deficiency (CSID) is an inherited disorder caused by a variation in the gene that codes for the enzyme sucrase-isomaltase. This means that in individuals who are affected by CSID, the gene that codes for the sucrase-isomaltase enzyme is altered in such a way that the individual’s cells are unable to produce functional sucrase-isomaltase.

Many genetic disorders, including CSID, result from a recessive pattern of inheritance.

One may inherit one copy of a gene variant from one parent, or two copies of a gene variant, one from each parent.

The sucrase-isomaltase gene (SI) is a very large gene, made up of more than 100,000 base pairs of DNA. As a result, there are many possible variants of the gene that codes for the enzyme sucrase-isomaltase. Most of these SI variants are benign, which means they do not impair the enzyme’s function. However, in a number of studies of individuals diagnosed with CSID, researchers have identified 37 gene variants that code for an impaired form of the enzyme sucrase-isomaltase, causing CSID.1-9Among these 37 known gene variants, four gene variants were the most common variants identified.9

As the name implies, sucrase-isomaltase is a complex enzyme containing two parts or subunits, sucrase and isomaltase. A genetic variant affecting either the sucrase or isomaltase region of the enzyme may affect the cell’s ability to produce the enzyme or the enzymatic activity of either sucrase or isomaltase, or both.10

Researchers have not yet studied all the gene variants that cause CSID. For this reason, there may be individuals who have had CSID symptoms from when they first ate solid food or early childhood who do not have one of the gene variants currently known to be associated with CSID.

The estimated prevalence of 
CSID in various populations

The prevalence of a CSID diagnosis, based on results from disaccharidase assays of intestinal tissue samples, was found to be relatively high in certain demographic groups:11

2% to 10% in indigenous Greenlanders
3% to 7% in indigenous people of Canada
3% in Alaskans of native ancestry

The prevalence of CSID in other North American and European populations has been estimated to be lower than in these groups, approximately 1 in 500 to 1 in 2,000 among non-Hispanic whites. This translates to a prevalence of approximately 0.05% to 0.2%. The prevalence is thought to be even lower in African-Americans and whites of Hispanic descent.12

It is possible that a significant proportion of children and adults affected with CSID are not being tested for CSID, and therefore are not being properly diagnosed or adequately treated. Because the gastrointestinal (GI) symptoms associated with CSID are similar to many other GI disorders, such as irritable bowel syndrome (IBS) or toddler’s diarrhea, and because CSID is rare, some researchers believe that many of those who are diagnosed with IBS may actually have undiagnosed CSID.

Our specialty
pharmacy

Learn how you can get Sucraid®
from our specialty pharmacy.

How to Order
References
  1. Alfalah M, Keiser M, Leeb T, et al. Compound heterozygous mutations affect protein folding and function in patients with congenital sucrase-isomaltase deficiency. Gastroenterology. 2009;136(3):883-92. doi:10.1053/j.gastro.2008.11.038
  2. Gericke B, Amiri M, Naim HY. The multiple roles of sucrase-isomaltase in the intestinal physiology. Mol Cell Pediatr. 2016;3(1):2. doi: 10.1186/s40348-016-0033-y
  3. Jacob R, Zimmer KP, Schmitz J, et al. Congenital sucrase-isomaltase deficiency arising from cleavage and secretion of a mutant form of the enzyme. J Clin Invest. 2000;106(2):281-7. doi:10.1172/JCI9677
  4. Keiser M, Alfalah M, Pröpsting MJ, et al. Altered folding, turnover, and polarized sorting act in concert to define a novel pathomechanism of congenital sucrase-isomaltase deficiency. J Biol Chem. 2006;281(20):14393-9. doi:10.1074/jbc.M513631200
  5. Naim HY, Heine M, Zimmer KP. Congenital sucrase-isomaltase deficiency: heterogeneity of inheritance, trafficking, and function of an intestinal enzyme complex. J Pediatr Gastroenterol Nutr. 2012;55(suppl 2):S13-20. doi: 10.1097/01.mpg.0000421402.57633.4b
  6. Ritz V, Alfalah M, Zimmer KP, et al. Congenital sucrase-isomaltase deficiency because of an accumulation of the mutant enzyme in the endoplasmic reticulum. Gastroenterology. 2003;125(6):1678-85. doi:10.1053/j.gastro.2003.09.022
  7. Sander P, Alfalah M, Keiser M, et al. Novel mutations in the human sucrase-isomaltase gene (SI) that cause congenital carbohydrate malabsorption. Human Mutat. 2006;27(1):119. doi: 10.1002/humu.9392
  8. Spodsberg N, Jacob R, Alfalah M, et al. Molecular basis of aberrant apical protein transport in an intestinal enzyme disorder. J Biol Chem. 2001;276(26):23506-10. doi:10.1074/jbc.C100219200
  9. Uhrich S, Wu Z, Huang J, Scott CR. Four mutations in the SI gene are responsible for the majority of clinical symptoms of CSID. J Pediatr Gastroenterol Nutr. 2012; 55(2):S34-5. doi:10.1097/01.mpg.0000421408.65257.b5
  10. Naim HY, Roth J, Sterchi EE, et al. Sucrase-isomaltase deficiency in humans. Different mutations disrupt intracellular transport, processing, and function of an intestinal brush border enzyme. J Clin Invest. 1988;82(2):667-679. doi:10.1172/JCI113646
  11. Treem WR. Congenital sucrase-isomaltase deficiency. J Pediatr Gastroenterol Nutr. 1995;21(1):1-14. doi:10.1097/00005176-199507000-00001
  12. Treem WR. Clinical aspects and treatment congenital sucrase-isomaltase deficiency. J Pediatr Gastroenterol Nutr. 2012;55(suppl 2):S7-S13. doi:10.1097/01.mpg.0000421401.57633.9

IMPORTANT SAFETY INFORMATION:

Important Safety Information for Sucraid® (sacrosidase) Oral Solution

  • Tell your doctor if you are allergic to, have ever had a reaction to, or have ever had difficulty taking yeast, yeast products, papain, or glycerin (glycerol).
  • Sucraid® may cause a serious allergic reaction. If you notice any swelling or have difficulty breathing, get emergency help right away.
  • Sucraid® does not break down some sugars that come from the digestion of starch. You may need to restrict the amount of starch in your diet. Your doctor will tell you if you should restrict starch in your diet.
  • Tell your doctor if you have diabetes, as your blood glucose levels may change if you begin taking Sucraid®. Your doctor will tell you if your diet or diabetes medicines need to be changed.
  • Some patients treated with Sucraid® may have worse abdominal pain, vomiting, nausea, or diarrhea. Constipation, difficulty sleeping, headache, nervousness, and dehydration have also occurred in patients treated with Sucraid®. Check with your doctor if you notice these or other side effects.
  • Sucraid® has not been tested to see if it works in patients with secondary (acquired) sucrase deficiency.
  • NEVER HEAT SUCRAID® OR PUT IT IN WARM OR HOT BEVERAGES OR INFANT FORMULA. Do not mix Sucraid® with fruit juice or take it with fruit juice. Take Sucraid® as prescribed by your doctor. Normally, half of the dose of Sucraid® is taken just before a meal or snack and the other half is taken during the meal or snack.
  • Sucraid® should be refrigerated at 36°F-46°F (2°C-8°C) and should be protected from heat and light; single-use containers can be removed from refrigeration and stored at 59°F-77°F (15°C-25°C) for up to 3 days (72 hours). Refer to Instructions for Use for full information on how to take Sucraid®.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.FDA.gov/medwatch or call 1-800-FDA-1088.

Indication

Sucraid® (sacrosidase) Oral Solution is indicated for the treatment of sucrase deficiency, which is part of congenital sucrase-isomaltase deficiency (CSID), in adult and pediatric patients 5 months of age and older.

Are you a healthcare professional?
Yes
No