Type I glycogen storage disease

Alternative names

Von Gierke disease

Definition

Von Gierke disease is a group of inherited metabolic disorders which involve increased glycogen storage. Since glycogen is needed to fuel muscles, problems with its metabolism can affect the whole body.

Some problems include slow growth, enlarged liver, gout, kidney failure, and chronic low blood sugar. In the past, von Gierke disease was associated with stunted growth, delayed or absent puberty, and early death.
With the development of treatments, growth, puberty, and quality of life have markedly improved.

Causes, incidence, and risk factors

All type I glycogen storage diseases are inherited in an autosomal recessive manner. Autosomal chromosomes are the non-sex chromosomes. If both parents are carriers of the mutated gene, each of their children has a 25% chance of inheriting the disease.

All the subtypes of this disease share a common feature - lack of proteins responsible for transporting or breaking down the components of glycogen. As a result, abnormal amounts of glycogen accumulate in various tissues, causing a wide range of symptoms.

Symptoms

• Severe low blood sugar (hypoglycemia)
  
• Doll-like features in children, including puffy cheeks, a thin chest and limbs and protuberant belly
  
• Intolerance of fasting, need for frequent feeding
  
• Stunted growth
  
• Delayed or underdeveloped puberty
  
• Enlarged liver
  
• Gout (a painful inflammation of joints)
  
• Easy bruising, nosebleeds
  
• Increased risk for infection and ulcers of the mouth or bowels due to malfunctioning white blood cells (in one type of the disease)
  

Signs and tests

• Enlarged liver with accumulated glycogen and fat on exam
  
• Liver tumors (adenomas)
  
• Low blood sugar (hypoglycemia)
  
• High blood uric acid (a risk factor for gout)
  
• High blood lactic acid
  
• Increase in blood lactic acid and failure to increase blood sugar when adrenalin or glucagon are administered
  
• High blood fats, especially triglycerides
  
• Inability to tolerate fasting
  
• Improvement in response to frequent feedings