Glycogen Storage Disease Type 0: Causes, Symptoms, and Treatment
Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 2, 2026.
What kind of doctor treats Glycogen Storage Disease Type 0?
A primary care doctor usually notices the first signs and orders early tests. Treatment is guided by a metabolic specialist, with a dietitian often helping build the eating plan. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is Glycogen Storage Disease Type 0?
Glycogen storage disease type 0 is a rare inherited condition that affects how the body stores and uses sugar. People with it have trouble keeping a steady blood sugar level, especially between meals. It is caused by missing or low activity of an enzyme.
Glycogen is the sugar your body stores in the liver and muscles for later use. In this condition, the liver cannot make glycogen properly, so it has no backup supply and blood sugar can drop too low between meals (fasting hypoglycemia).
Symptoms
The most common sign is low blood sugar after going without food, such as overnight. Signs include sweating, shakiness, tiredness, pale skin, hunger, and trouble concentrating. Some children have seizures.
Causes and who gets it
This disease is genetic, passed down through families. A child must get one changed copy of the gene from each parent; parents usually carry it without symptoms. It affects glycogen synthase, the enzyme that builds liver glycogen, and is very rare.
How doctors diagnose it
Doctors start by asking about symptoms and checking blood sugar after fasting. Blood and urine tests can show patterns suggesting the liver is not storing glycogen properly. Genetic testing can confirm the diagnosis.
Treatment
The main goal is keeping blood sugar steady. Most people eat frequent meals and snacks, including a bedtime snack. Some drink cornstarch in liquid, which releases sugar slowly over hours. Plans are made with a metabolic specialist and need lifelong attention.
When to see a doctor
See a doctor if a child has unexplained shakiness, sweating, confusion, or extreme tiredness, especially when meals are missed. Seizures or fainting need urgent care.
How a direct primary care or concierge doctor fits in
A direct primary care doctor is paid a flat monthly fee instead of billing insurance per visit; a concierge doctor works similarly but charges more. They can order tests, watch growth, and manage follow-up, referring to a metabolic specialist when needed.
Common questions
Can glycogen storage disease type 0 be cured?
There is no cure, because the condition comes from a changed gene. Most people manage it well with a careful eating schedule and regular monitoring. How well someone does depends on how severe their condition is and how closely they follow their plan.
Does this condition affect the muscles?
Unlike some other glycogen storage diseases, type 0 mainly affects the liver and blood sugar. Muscle symptoms are not the main problem. A doctor can explain how the different types compare.
Can adults have this condition?
Yes, though it is usually found in childhood. Some people with mild symptoms are not diagnosed until later in life. Adults who have repeated low blood sugar episodes should mention this to their doctor.
Is it safe for children with this condition to fast before surgery or tests?
Fasting can be risky for people with this condition, so doctors need to know about the diagnosis before any procedure. The care team can adjust the plan to keep blood sugar steady. Always tell every doctor involved about the condition ahead of time.
Sources
- NIH Genetic and Rare Diseases Information Center - Glycogen storage disorder due to hepatic glycogen synthase deficiency
- MedlinePlus Genetics - Glycogen storage disease type 0
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
