IEMbase 0668: SI-related sucrase-isomaltase deficiency
Scope
| Field | Value |
|---|---|
| IEMbase ID | 668 |
| Nosology | 3.6.04.01 |
| Nosology code | IEM0318 |
| Gene | SI |
| External IDs | OMIM:222900; ORPHA:306486 |
| Generated mapping | MAPPED to Congenital_Sucrase-Isomaltase_Deficiency.yaml |
| Candidate DisMech targets | Congenital_Sucrase-Isomaltase_Deficiency.yaml |
| Review date | 2026-07-07 |
IEMbase phenotype signal
IEMbase represents autosomal recessive SI-related sucrase-isomaltase deficiency, also labeled congenital sucrase-isomaltase deficiency, disaccharide intolerance I, and congenital sucrose intolerance.
Biochemical rows include markedly decreased mucosal sucrase activity, decreased to very low mucosal isomaltase activity, normal stool reducing sugars, and normal to low plasma sodium. Clinical rows include malabsorption, failure to thrive, diarrhea, profuse osmotic diarrhea, dehydration, and possible urolithiasis from infancy onward.
DisMech phenotype coverage
Congenital_Sucrase-Isomaltase_Deficiency.yaml is an exact local target. It
models biallelic SI variants, brush-border sucrase-isomaltase deficiency,
impaired digestion of sucrose and starch, osmotic diarrhea, bloating,
flatulence, abdominal pain, vomiting, failure to thrive, malnutrition, and
diagnostic sucrase/isomaltase enzyme testing.
The local entry also captures dietary treatment and sacrosidase-relevant management context.
Concordance and completeness
Judgement: exact high-concordance mapping.
IEMbase and DisMech agree on the intestinal brush-border enzyme defect, decreased sucrase/isomaltase activity, carbohydrate malabsorption, osmotic diarrhea, and growth/nutrition consequences. IEMbase adds several row-level prompts that are thinner locally: sodium directionality, normal reducing sugars, dehydration, and urolithiasis.
Curation actions
- Keep
Congenital_Sucrase-Isomaltase_Deficiency.yamlas the disease-level target. - Preserve decreased mucosal sucrase and isomaltase activities as diagnostic anchors.
- Review dehydration, sodium abnormalities, normal stool reducing sugars, and urolithiasis as possible enrichment prompts.
- Maintain the distinction from other disaccharidase deficiencies and generalized malabsorption syndromes.