What is the treatment for Congenital Sucrase-Isomaltase Deficiency (CSID)?

Treatment of Congenital Sucrase-Isomaltase Deficiency (CSID)

The primary treatment for CSID is sacrosidase (Sucraid) enzyme replacement therapy, FDA-approved for patients 5 months of age and older, combined with dietary sucrose restriction tailored to individual symptom tolerance. 1

Enzyme Replacement Therapy

Sacrosidase is the cornerstone of CSID management and provides marked symptom reduction in patients who fail dietary management alone. 2

Dosing and Administration

• Weight-based dosing: Patients ≤15 kg receive 1 mL per meal or snack; patients >15 kg receive 2 mL per meal or snack 3
• Administer with each meal or snack containing sucrose or starch 1
• Mix with water, milk, or infant formula only—avoid fruit juice as acidity reduces enzyme activity 1
• The enzyme is broken down in the GI tract and absorbed as amino acids and peptides 1

Clinical Efficacy

• Randomized controlled trials demonstrate significant reduction in breath hydrogen excretion, stool frequency, and GI symptoms (diarrhea, abdominal pain, bloating, gas) compared to placebo 3
• All six patients in one case series showed marked symptom improvement with sacrosidase after failing dietary management alone 2
• Patients report considerable improvement in symptoms and quality of life after treatment initiation 4

Dietary Management

Dietary sucrose restriction should be implemented alongside sacrosidase, as the enzyme does not replace isomaltase activity and patients may continue experiencing symptoms from starch ingestion. 1

Specific Dietary Modifications

• Restrict or eliminate sucrose-containing foods (table sugar, fruits, fruit juices) based on individual tolerance 2, 5
• Consider starch restriction, particularly in patients whose symptoms are not adequately controlled by sacrosidase alone 1
• Tailor restrictions to individual symptom severity and tolerance rather than implementing blanket elimination 5
• Symptoms typically worsen after ingestion of fruits, juices, grains, and starches 6

Special Considerations and Monitoring

Diabetes Mellitus

• Monitor blood glucose concentrations closely in diabetic patients, as sacrosidase enables absorption of glucose and fructose from sucrose hydrolysis, potentially increasing blood glucose 1
• Adjust diet accordingly based on glucose monitoring results 1

Persistent Symptoms

• Some patients require continued starch restriction even with sacrosidase therapy due to residual isomaltase deficiency 1, 5
• Persistent symptoms indicate areas of unmet need and may require further dietary modification 4

Safety Profile

• Sacrosidase is well-tolerated with minimal adverse events 2, 3
• One case of wheezing occurred in a child with pre-existing asthma history 3
• No teratogenic effects expected; use in pregnancy only if clearly needed 1

Common Pitfalls to Avoid

• Do not administer sacrosidase with fruit juice, as acidity destroys enzyme activity 1
• Do not rely on dietary restriction alone as first-line therapy—most patients show little improvement with diet modification without enzyme replacement 2
• Do not assume sacrosidase eliminates need for all dietary modification—starch restriction may still be necessary due to persistent isomaltase deficiency 1, 5
• Recognize that CSID diagnosis is often delayed for years due to nonspecific symptoms overlapping with irritable bowel syndrome 6, 5