Secondary Logo

Share this article on:

Phenotypic Observations by the CSID Dietary and Medical Support Group

Slawson, Mary H.

Journal of Pediatric Gastroenterology and Nutrition: November 2012 - Volume 55 - Issue - p S30–S32
doi: 10.1097/01.mpg.0000421406.80504.1d
Supplement Articles

CSID Parent Support Group, Provo, Utah.

Address correspondence and reprint requests to Mary H. Slawson, CSID Parent Support Group, 942 South 1230 East, Provo, UT 84606 (e-mail:

The author reports no conflicts of interest.

For 16 years, the congenital sucrase-isomaltase deficiency (CSID) parent support group has followed 7433 individuals diagnosed by small bowel biopsy with CSID: children (848 ages 0 to 2 years, 1722 ages 3 to 4 years, 1241 ages 5 to 8 years, and 2422 ages 9 to 17 years), adults (1200), and >44,000 blood-related relatives. Based on small bowel biopsy results and detailed clinical dietary history, 5 different clinical phenotypes have been proposed for which specific diet regimens have been developed. Patients following these diets report significant improvement in their symptoms. This article provides a brief overview of the proposed phenotypes and diet recommendations identified by the parent support group. Available enzyme therapies are discussed.

Back to Top | Article Outline


Table 1 identifies the proposed clinical phenotypes based on the reduction in small intestinal disaccharidase activities and dietary tolerance among those patients with CSID followed by the support group. The range of mucosal biopsy activities is taken from Table 2, which summarizes 3 patterns of CSID disaccharidase mucosal enzyme deficiencies described in the literature (1–7) and in this workshop (8–11) and makes a tentative correlation with the dietary tolerances in Table 1. One goal of future research is to confirm whether these 5 dietary phenotypes correlate with 3 mutant genotypes of SI. The enzymatic recognition of SCID is presently limited to biopsies with lactase activities >10 enzyme units (1–10), but there may be others within the large group of sucrase deficiencies with lactase activities falling below this level that await identification by new methods of genetic analysis (12).





Back to Top | Article Outline


None of the patients in any of the phenotypes can tolerate the following sweeteners: hydrogenated glucose syrup, galactose/maltose/malt sugar, acesulfame K, maltitol/maltitol syrup, brown rice syrup, NutraSweet/neotame, or Stevia/diterpene glycosides. Sucrose can be tolerated in only extremely small amounts without enzyme supplementation, whereas crystalline glucose, dextrose, corn syrup, crystalline fructose/levulose, and Equal can be used without problems. Specific dietary recommendations are available for patients and families with variations of CSID phenotype and can be found at Food recommendations were developed only after an extensive review of food diaries.

Back to Top | Article Outline


The CSID Parent Support Group has had experience with 4 enzyme replacements for patients with CSID. Without enzyme replacement, patients are limited to approximately 100 foods they can eat without difficulty. With enzyme replacement, this number increases to approximately 400 foods, significantly improving the patient's nutrition and dietary selection. Specific enzyme supplement and diet recommendations are available from the CSID Support Group for each phenotype:

  1. Sucraid (United States) manufactured by QOL Medical LLC. E-mail:
  2. Bi-Myconase (the Netherlands, supplies Europe) manufactured by EPC Pharma. E-mail: and Web site Other over-the-counter multiglucosidase enzymes are available worldwide.
  3. Digestion Formula Forte (Canada) is manufactured by Future Formulations. E-mail: Other over-the-counter multiglucosidase enzymes are available worldwide.
  4. Lactase is manufactured by McNeil Nutritionals LLC. Other over-the-counter oral lactase enzymes are available worldwide.
Back to Top | Article Outline


The CSID parent support group has developed a specific diet for each phenotype based upon small intestinal assays of enzyme activity and careful review of dietary diaries. This information is available to anyone diagnosed as having this condition and is available online at Enzymes therapies are available worldwide, and appropriate suggestions are available upon request.

Back to Top | Article Outline


1. Auricchio S, Ciccimarra F, Moauro L, et al. Intraluminal and mucosal starch digestion in congenital deficiency of intestinal sucrase and isomaltase activities. Pediatr Res 1972; 832–839.
2. Robayo-Torres CC, Opekun AR, Quezada-Calvillo R, et al. 13C-breath tests for sucrose digestion in congenital sucrase isomaltase-deficient and sacrosidase-supplemented patients. J Pediatr Gastroenterol Nutr 2009; 48:412–418.
3. Sander P, Alfalah M, Keiser M, et al. Novel mutations in the human sucrase-isomaltase gene (SI) that cause congenital carbohydrate malabsorption. Hum Mutat 2006; 27:119.
4. Treem WR, Ahsan N, Sullivan B, et al. Evaluation of liquid yeast-derived sucrase enzyme replacement in patients with sucrase-isomaltase deficiency. Gastroenterology 1993; 105:1061–1068.
5. Skovbjerg H, Krasilnikoff PA. Immunoelectrophoretic studies on human small intestinal brush border proteins. The residual isomaltase in sucrose intolerant patients. Pediatr Res 1981; 15:214–218.
6. Schmitz J, Bresson JL, Triadou N, et al. Polyacrylamide gel electrophoresis analysis of membrane proteins of microvilli and of a cytoplasmic fraction in 8 cases of congenital saccharose intolerance. Gastroenterol Clin Biol 1980; 4:251–256.
7. Antonowicz I, Lloyd-Still JD, Khaw KT, et al. Congenital sucrase-isomaltase deficiency. Observations over a period of 6 years. Pediatrics 1972; 49:847–853.
8. Naim HY, Heine M, Zimmer K-P. 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.
9. Nichols BL, Adams B, Roach C, et al. Frequency of sucrase deficiency in mucosal biopsies. J Pediatr Gastroenterol Nutr 2012; 55(Suppl 2):S2–7.
10. Treem WR. Clinical aspects and treatment of congenital sucrase-isomaltase deficiency. J Pediatr Gastroenterol Nutr 2012; 55(Suppl 2):S7–11.
11. Zimmer KP, Scholz D, Naim HY. Transient sucrose and starch intolerance. J Pediatr Gastroenterol Nutr 2012; 55(Suppl 2):S39–40.
12. Uhrich S, Wu ZN, Huang JY, et al. Four mutations in the SI gene are responsible for the majority of children with clinical symptoms from sucrase-isomaltase deficiency. J Pediatr Gastroenterol Nutr 2012; 55(Suppl 2):S34–5.
Copyright 2012 by ESPGHAN and NASPGHAN