Digestion breaks down food into subunits and processed to provide energy and nutrients to the body organs and tissues. The stomach, liver, pancreas and small intestine produce the digestive enzymes used for food breakdown and processing. Several inherited disorders cause deficiencies in one or more digestive enzymes, leading to serious and potentially life-threatening diseases. Dietary restriction is the primary form of treatment for diseases caused by lack of digestive enzymes.
Lactase Deficiency
Congenital lactase deficiency is a rare, inherited disorder. With this condition, a genetic mutation leads to absence of functional lactase, the enzyme that breaks down milk sugar. Patients with congenital lactase deficiency typically become ill within the first few days of life, with severe diarrhea, vomiting, weight loss and dehydration, reports the University of Illinois Medical Center. Without early treatment, liver damage may occur. Elimination of all forms of milk, including breast milk, from the diet typically leads to symptomatic recovery.
Congenital lactase deficiency differs from the common disorder known as lactose intolerance. Lactose intolerance is not a genetic disease, but rather, a condition caused by reduced lactase production as a person ages.
Galactose Sugar
Galactosemia is an inherited disease that occurs in one out of every 10,000 to 30,000 births, according to Gene Reviews. The disease is caused by a genetic defect that affects the production or function of the enzymes that break down the sugar galactose. Within a few days of birth, galactose accumulates in the bloodstream, causing vomiting, diarrhea, poor feeding, liver inflammation and bleeding abnormalities. Undiagnosed galactosemia can lead to permanent brain damage, liver failure or death in early infancy.
Galactose occurs in many foods, including milk and milk products, and certain fruits, vegetables and beans, reports the nonprofit organization Parents of Galactosemic Children. Treatment centers on the elimination of all milk and galactose from the diet.
Hereditary Fructose Intolerance
The digestive enzyme aldolase B breaks down the sugar fructose, which occurs naturally in fruit. Table sugar, or sucrose, also contains fructose. Patients with hereditary fructose intolerance produce little or no functional aldolase B. The accumulation of fructose in the bloodstream severely disrupts normal body chemistry, leading to potentially life-threatening, low blood glucose levels, notes Boston University. Untreated hereditary fructose intolerance may lead to seizures, coma, and kidney and liver failure. Treatment for hereditary fructose intolerance involves elimination of the sugar from the diet, which typically leads to rapid symptomatic recovery.
References
- University of Illinois Medical Center: Lactose Intolerance
- Food Reactions: Types of Lactose Intolerance
- Gene Reviews: Galactosemia
- Parents of Galactosemic Children: Galactose Contents of Foods
- HFI Laboratory at Boston University: Specifics of HFI and Its Diagnosis
- MedlinePlus: Hereditary Fructose Intolerance
