Definition of Von Gierke disease:

Von Gierke disease is a condition in which the body cannot break down glycogen for energy. Gycogen is stored in the liver and muscles and is normally broken down into glucose when you do not eat.

Von Gierke disease is also called Type I glycogen storage disease (GSD I).

Causes, incidence, and risk factors:

Von Gierke disease occurs when the body lacks the protein (enzyme) that releases glucose from glycogen. This causes abnormal amounts of glycogen to build up in certain tissues. When glycogen is not broken down properly, it leads to low blood sugar.

Von Gierke disease is inherited, which means it is passed down through families. If both parents carry the defective gene related to this condition, each of their children has a 25% chance of developing the disease.

Symptoms:

• Constant hunger and need to eat often
• Easy bruising and nosebleeds
• Fatigue
• Irritability
• Puffy cheeks, thin chest and limbs, and swollen belly

Signs and tests:

The health care provider will perform a physical exam.

There may be signs of:

• Delayed puberty
• Enlarged liver
• Gout
• Inflammatory bowel disease
• Liver tumors
• Severe low blood sugar (hypoglycemia)
• Stunted growth or failure to grow

Children with this condition are usually diagnosed before age 1.

Tests that may be done include:

• Biopsy of liver or kidney
• Blood sugar test
• Genetic testing
• Lactic acid blood test
• Triglyceride level
• Uric acid blood test

Testing reveals low blood sugar and high levels of lactate, lipids, and uric acid.

Treatment:

The goal of treatment is to avoid low blood sugar. Eat frequently during the day, especially foods that contain carbohydrates (starches). Older children and adults may take cornstarch by mouth.

Overnight, a feeding tube is placed through the nose into the stomach to provide sugars or uncooked cornstarch. The tube can be put in at bedtime and taken out each morning.

A medication called allopurinol can lower blood uric acid and decrease the risk for gout. Other medications may include those for kidney disease, high lipids, and to increase the cells that fight infection.

Persons with von Gierke disease cannot properly break down fruit or milk sugar. It is best to avoid these products.

Support Groups:

Association for Glycogen Storage Disease -- www.agsdus.org

Expectations (prognosis):

Since treatments have been developed, growth, puberty, and quality of life have improved for people with von Gierke disease. Those who are identified and carefully treated at a young age can live into adulthood.

Early treatment also decreases the rate of severe problems such as:

• Gout
• Kidney failure
• Life-threatening low blood sugar
• Liver tumors

Complications:

• Frequent infection
• Gout
• Kidney failure
• Liver tumors
• Osteoporosis
• Seizures, lethargy, confusion due to low blood sugar
• Short height
• Underdeveloped secondary sexual characteristics (breasts, pubic hair)
• Ulcers of the mouth or bowel

Calling your health care provider:

Call your health care provider if you have a family history of glycogen storage disease or early infant death due to low blood sugar.

Prevention:

There is no simple way to prevent glycogen storage disease.

Couples who wish to have a baby may seek genetic counseling and testing to determine their risk for passing on von Gierke disease.