E74.01 von Gierke disease

Name of the Condition

• von Gierke disease (ICD-10 Code E74.01)

Summary

von Gierke disease is a type of glycogen storage disease characterized by a deficiency of the enzyme glucose-6-phosphatase. This deficiency impairs the liver's ability to convert glycogen into glucose, leading to abnormal glycogen accumulation in the liver and kidneys. The condition disrupts glucose homeostasis, resulting in hypoglycemia and other metabolic complications.

Causes

von Gierke disease is caused by genetic mutations in the G6PC gene, which encodes glucose-6-phosphatase. These mutations are inherited in an autosomal recessive pattern, meaning both parents must carry a mutated gene for a child to be affected. The enzyme deficiency disrupts glycogen breakdown, preventing the liver from maintaining normal blood glucose levels.

Risk Factors

• Genetic predisposition or family history of von Gierke disease.
• Consanguinity (closely related parents), increasing the likelihood of inheriting recessive mutations.
• Ethnic or population-specific prevalence for certain genetic variants.

Symptoms

Symptoms typically appear in infancy or early childhood and may include:

• Severe hypoglycemia, especially during fasting or illness.
• Enlarged liver (hepatomegaly) due to glycogen accumulation.
• Growth delays or failure to thrive.
• Lactic acidosis and hyperlipidemia.
• Increased risk of infections or bleeding due to impaired glucose metabolism.

Diagnosis

Diagnosis involves clinical evaluation, family history, and laboratory tests. Blood tests may show low glucose, elevated lactate, and abnormal lipid levels. Imaging studies (e.g., ultrasound) can confirm hepatomegaly. Genetic testing or enzyme activity assays may be used to confirm the specific enzyme deficiency.

Treatment Options

Treatment focuses on maintaining normal blood glucose levels and managing symptoms. This may include:

• Frequent feeding or continuous glucose infusion to prevent hypoglycemia.
• Uncooked cornstarch therapy to provide a slow-release glucose source.
• Monitoring and managing complications such as lactic acidosis or hyperlipidemia.
• Liver transplantation in severe cases.

Prognosis and Follow-Up

With proper management, individuals with von Gierke disease can lead relatively normal lives. Regular follow-up is essential to monitor growth, liver function, and metabolic status. Long-term complications, such as liver adenomas or renal disease, may require additional interventions.

Complications

Potential complications include:

• Liver adenomas or hepatocellular carcinoma due to chronic glycogen accumulation.
• Renal dysfunction or kidney stones.
• Osteoporosis or bone fractures.
• Delayed puberty or growth impairment.
• Increased risk of infections or metabolic crises.

Lifestyle & Prevention

• Maintain a consistent feeding schedule to prevent hypoglycemia.
• Avoid fasting or prolonged periods without food.
• Work with a dietitian to develop a balanced meal plan.
• Monitor blood glucose levels regularly, especially during illness.
• Stay hydrated and avoid excessive physical exertion without proper nutrition.

When to Seek Professional Help

Seek medical attention if you or your child experiences:

• Persistent hypoglycemia symptoms (e.g., lethargy, seizures).
• Unexplained weight loss or growth delays.
• Severe abdominal pain or jaundice.
• Signs of infection or metabolic crisis (e.g., vomiting, rapid breathing).

Tips for Medical Coders

When coding for von Gierke disease (E74.01), ensure documentation supports the diagnosis, including clinical findings, laboratory results, or genetic testing. Verify that the code is used for the specific subtype of glycogen storage disease caused by glucose-6-phosphatase deficiency. Avoid using this code for other glycogen storage disease subtypes without clear clinical differentiation.