Congenital Sucrase-Isomaltase Deficiency (CSID) is a rare gastrointestinal disorder where patients have difficulty digesting sugar (sucrose) and starch. Diet modification is an effective treatment for genetically determined sucrase deficiency or CSID. Initially, diet modification may be the only thing that will alleviate the uncomfortable and sometimes painful symptoms of the condition. When CSID is the cause of acute diarrhea, abdominal pain, gas, bloating and vomiting, it is because the patient lacks the enzymes necessary to process sugar and starch. Because sugar and starch are two major elements in most people’s typical diets, reducing their intake would mean restricting the diet considerably. Since there is no cure for CSID, the inability to digest sugar and starch typically remains well into adulthood. CSID is a genetic condition that will not be outgrown over time.
Eliminating fruits, fruit juices, table sugar and many starches may initially sound reasonable, but that leaves little else that can be included to provide a balanced diet. Certainly a physician and/or a dietitian would be the best experts to give advice on how to alter the diet depending on the patient. This is because different people may be able to tolerate different amounts of sugar or starches. Some CSID patients can tolerate very little sucrose and starch, while other patients can tolerate some sucrose and starch if ingested with other foods. Unfortunately there is not an exact solution across the board for all patients with Congenital Sucrase-Isomaltase Deficiency. A low-sucrose, low-starch diet can be difficult to follow and may lead to weight loss and vitamin and mineral deficiencies.
There are also pharmacological treatments for this deficiency. Patients should check with their doctors to see if these are right for them.