HomeHealth articlesInternal Medicineglycogen storage disease
Genetic Disorders

Glycogen Storage Diseases - Types, Causes, Diagnosis, and Treatment

Verified data

5 min read

Share
Facebook Telegram LinkedIn WhatsApp

Outline

Glycogen storage disease (GSD) is a rare metabolic disorder. Read the article below to learn more.

Medically reviewed by Dr. Basuki Nath Bhagat
Published At February 23, 2023
Reviewed At October 5, 2023

Education:

BDS

Professional Bio:

Dr. Shaivy Dubey is a Dental Surgeon with three years of clinical experience. She completed her BDS in 2021 from Rishiraj College of Dental Science and Research Centre, Bhopal, Madhya Pradesh, India. She is well-trained in diagnosing and treating dental conditions and diseases of the oral cavity.

This doctor is not available for online consultations on the platform anymore.

Consult other doctors in the same speciality

Education:

MBBS

Professional Bio:

Dr. Basuki Nath Bhagat is a General Practitioner with eight years of clinical experience. He completed his MBBS at Government Theni Medical College, Tamilnadu. He specializes in treating acute and chronic illnesses and providing patients with preventive care and health education. He also aims to consider the biological, psychological, and social factors relevant to the care of each patient's illness.

This doctor is not available for online consultations on the platform anymore.

Consult other doctors in the same speciality
Table of Contents

What Is Glycogen?

Glycogen can be described as a stored form of glucose that comprises many connected glucose molecules. Glucose is a source of energy for the body to function efficiently. It is found in the form of carbohydrates in several types of foods and fluids a person consumes. When the body does not need glucose from a person's food for energy, it stores glucose primarily in the muscles and the liver as glycogen for use.

The body produces glycogen from glucose through a process called glycogenesis, and the body breaks down glycogen for use through glycogenolysis. Several different enzymes also take part in these two processes.

The enzyme is a protein in a cell that acts as a catalyst and allows certain bodily processes to occur. There are thousands of enzymes present in the body which have important functions.

Where Is Glycogen Stored in the Body?

The body stores glycogen in the different body parts, like the liver and skeletal muscles, with small amounts in the brain. The liver stores a large amount of glycogen than the skeletal muscles. About three-quarters of the body's total glycogen is stored in the muscles as the total muscle mass exceeds the liver. During extreme and prolonged exercise, the glycogen in the active muscle cells can substantially reduce. The amount of glycogen in the liver cells varies throughout each day depending on factors that include:

  • The number of carbohydrates a person consumes.

  • The length of time between the meals.

  • The intensity and duration of recent physical activity.

After 12 to 24 hours of fasting, liver glycogen is used completely.

What Is Glycogen Storage Disease?

Glycogen storage disease (GSD) is a group of disorders that interfere with the body's ability to convert glycogen into glucose. According to the type of glycogen storage disease, a child's glycogen may build up in the liver, muscles, or both. Glycogen storage disease can also affect blood cells, kidneys, the heart, and other internal organs.

Glycogen is the body's main source of energy. Generally, glycogen is stored in the liver until the body needs energy. Then, enzymes convert glycogen into glucose to pass through the bloodstream to cells that require fuel for effective functioning. Each cell in the body contains enzymes, but children with GSD lack one of the enzymes responsible for converting glycogen to glucose.

Glycogen storage disease is a rare condition. The National Organization for Rare Diseases states that glycogen storage disease affects fewer than 1 in 40,000 people in the United States.

What Are the Types of Glycogen Storage Disease?

There are many types of glycogen storage disease (GSD), based on which enzyme is missing. Some types only affect the liver, others only the muscles, while others affect the liver and the muscles. Each type has slightly different symptoms. Treatments vary with the disease variant.

The most prevalent types of glycogen storage disease (GSD) are:

  1. Glycogen Storage Disease Type I (GSD I) - It is also known as Von Gierke disease and accounts for about 25 percent of all children with glycogen storage disease (GSD). Symptoms mostly appear when a kid is 3 to 4 months of age, and symptoms may include hypoglycemia (low blood sugar), which can lead to fatigue, crankiness, and constant hunger. The liver and sometimes the kidneys swell due to built-up glycogen.

  2. Glycogen Storage Disease Type III (GSD III) - It is also known as Cori disease or Forbes disease, which results in the building up of glycogen in the liver and muscles. Symptoms appear within a few months of life. Children with type III of GSD may have a swollen belly, delayed growth, and weak muscles.

  3. Glycogen Storage Disease Type IV (GSD IV) - It is also known as Andersen disease and is one of the most serious types of GSD. Symptoms typically appear in a child's first month of life and include failure to gain weight or growth at an expected rate. This type of GSD often leads to liver cirrhosis and can also affect the heart and other organs. The child's outcomes depend on the form of GSD IV they inherit.

What Are the Causes of Glycogen Storage Disease?

Glycogen storage disease is a rare and genetically inherited disease. Parents may have an abnormal gene pair that gets transferred to their child, and the child gets glycogen storage disease by birth. However, their parents typically do not have the disease or show any symptoms.

Children with glycogen storage disease lack one of the enzymes responsible for converting glycogen to glucose. As a result, their muscles do not get the nutrition they need to grow, and glycogen builds up in their liver and other organs.

What Are the Signs and Symptoms of Glycogen Storage Disease?

Symptoms of glycogen storage disease typically appear early, when a child is still a baby or a very young child. Though symptoms vary depending on the glycogen storage disease variant, the following symptoms are common:

  • Delayed growth.

  • Easy bruising.

  • Swollen belly.

  • Muscle pain and cramping.

  • Weak muscles.

  • Irritability.

  • Chronic hunger.

What Are the Risks of Glycogen Storage Disease?

Based on the variant, glycogen storage disease has risks related to it. Children with type I (GSD I) are observed to suffer from low blood sugar. This type of glycogen storage disease can also lead to lactic acidosis, a buildup of lactic acid, which can lead to painful muscle cramps. As they grow and come into adolescence, children with GSD I may have delayed puberty and weak bones (osteoporosis). Other risks include:

  • Gout is a type of arthritis.

  • Adenomas are tumors of the liver that are usually benign (non-cancerous).

  • Inflammatory bowel disease (IBD).

  • Dental problems.

  • Recurring infections.

  • Pulmonary hypertension.

Children with type III (GSD III) tend to have problems like low blood sugar and excess fat. In addition, as a child grows, the liver may become enlarged. In some children, the liver returns to its normal size when they enter adolescence, while others may develop liver cirrhosis or liver failure. Children with type III glycogen storage disease are also at risk for:

  • Slow growth.

  • Muscle weakness.

  • Short stature.

Children with Type IV (GSD IV) may not have low blood sugar but can develop early complications. Children who have GSD IV are at risk for the following complications:

  • Slow weight gain.

  • Muscle weakness, including a weak heart muscle.

  • Cirrhosis.

  • Portal hypertension.

How Is Glycogen Storage Disease Diagnosed?

  • For an accurate diagnosis recording the patient's health history is vital.

  • The child's doctor may inquire about the symptoms, overall health, and day-to-day activities.

  • The doctor will also conduct a physical exam and check for vital signs, liver enlargement, and muscle weakness.

  • The doctor may indicate some blood tests and possibly a liver or muscle biopsy so that samples can be tested for enzyme levels to help determine if a child has glycogen storage disease.

How Is Glycogen Storage Disease Treated?

There is currently no treatment for glycogen storage disease. After diagnosis, several specialties are normally involved in caring for children with glycogen storage disease, including specialists for metabolism and endocrinology. Based on the glycogen storage disease variant, the child's treatment would typically focus on promoting their growth and development and maintaining a healthy glucose level in the blood.

The health care provider will recommend small, frequent meals for the day. The meals should be low in sugar to prevent glycogen from building up in the liver. In addition, uncooked cornstarch can help maintain a healthy blood sugar level. In some cases, doctors may advise a nasogastric tube or gastrostomy (G tube) that delivers a continuous supply of nutrition while the child is sleeping. Children with GSD IV may need a liver transplant if the disease progresses to liver cirrhosis or liver failure.

Conclusion

Glycogen storage disease is a rare condition that is mostly seen in children. It can affect the child's growth and development. And as the disease is caused mainly due to gene mutation, there is no cure. Children and individuals with this condition can lead a normal and productive life if care is taken to observe to follow the medical directions adequately. In addition, maintaining a healthy lifestyle is essential to prevent disease progression and quality of life.

Listen to related tracks in our music library

Frequently Asked Questions

What Is the Rate of Prevalence of Glycogen Storage Disease Type 1?

A hereditary illness called glycogen storage disease type 1 (GSD1) impairs the body's capacity to convert glycogen to glucose, which causes an accumulation of glycogen in several organs, most notably the liver and kidneys. The prevalence of GSD1 varies widely among different populations, ranging from one in 20,000 to 100,000 live births. The prevalence may be higher in certain populations, such as Amish and Ashkenazi Jewish communities.

How Is Glycogen Storage Disease Inherited?

Glycogen storage diseases, including GSD1, are inherited in an autosomal recessive pattern. To develop the condition, an affected individual must inherit two copies of this mutated gene, one from each parent. If both parents are carriers of the gene mutation, each of the children has a 25 percent chance of the mutation and therefore has the disease.

What Is the Survival Rate of Individuals with Glycogen Storage Disease?

The survival rate of individuals with glycogen storage disease depends on the severity of their condition, the organs affected, and the management of their symptoms. In some cases, GSD1 can be life-threatening, particularly in infants with severe disease. However, with appropriate treatment and management, including dietary and medical interventions, many individuals with GSD1 can live a normal lifespan.

What Is the Recommended Nutritional Management for Individuals with Glycogen Storage Disease?

The recommended nutritional management for individuals with glycogen storage disease involves a diet low in simple carbohydrates and high in protein and complex carbohydrates. This regulates blood sugar levels and prevents glycogen accumulation in the liver and kidneys. In some cases, individuals may also require medical interventions, such as glucose infusions or liver transplantation, to manage their symptoms.

What Is the Life Expectancy of Individuals with Glycogen Storage Disease?

The life expectancy of individuals with glycogen storage disease depends on various factors, including the severity of the disease, the organs affected, and the effectiveness of their management and treatment. In general, individuals with GSD1 can live a normal lifespan with appropriate management, although some may experience complications that can impact their quality of life or lead to a shortened lifespan.

Is There a Cure for Glycogen Storage Disease?

There is no known cure for glycogen storage diseases, including GSD1. Treatment is based on managing symptoms and preventing complications, such as hypoglycemia, metabolic acidosis, and liver and kidney damage. Treatment may involve dietary modifications, medication, and, in some cases, liver transplantation. Researchers are developing new treatments and therapies for GSD1 and other glycogen-storage diseases.

How Long Does Glycogen Storage Last?

Glycogen storage lasts for a variable amount of time, depending on the individual's metabolic rate, level of physical activity, and diet. Glycogen is converted into glucose and used as fuel when a body requires energy. The rate at which glycogen is depleted and replenished can vary widely depending on these factors. Generally, glycogen stores can last several hours to a day or two.

What Are the Complications Associated with Glycogen Storage Disease?

Depending on the disease's severity and the organs affected, glycogen storage diseases, including GSD1, may result in complications. Individuals with GSD1 may sometimes experience hypoglycemia, metabolic acidosis, growth delays, liver and kidney damage, or other complications. Proper management and treatment, including dietary modifications and medical interventions, can help to prevent or manage these complications.

How Does Glycogen Storage Disease Affect Infants?

Depending on the disease's severity and the organs affected, glycogen storage disorder can have a variety of effects on newborns. Hypoglycemia, convulsions, respiratory distress, and other problems are possible in infants with the severe type of GSD1. Early diagnosis and appropriate management and treatment are critical for the health and survival of infants with GSD1.

Can Glycogen Storage Disease Cause Weight Loss?

Glycogen storage disease, including GSD1, can cause weight loss in some individuals. This can occur due to the body's inability to properly store and use glucose for energy, leading to a breakdown of fat energy stores. However, weight gain may also occur in some cases due to the buildup of glycogen in the liver and other organs. Proper management and treatment, including dietary modifications, can help to regulate weight and prevent complications associated with GSD1.

Which Organs in the Body Store Glycogen?

The liver and muscles are the primary organs in the body that store glycogen. The liver stores glycogen to regulate blood sugar levels, while muscles store glycogen for energy during exercise and physical activity. The amount of glycogen stored in these organs can vary widely depending on an individual's diet, physical activity, and metabolic rate.

What Are Some Foods That Contain Glycogen?

Glycogen is primarily found in carbohydrate-rich foods, including grains, legumes, fruits, and vegetables. Some foods containing glycogen include bread, pasta, rice, potatoes, corn, peas, bananas, and grapes. Glycogen can also be synthesized in the liver from glucose.

What Is the Maximum Amount of Glycogen That Can Be Stored in the Body?

The maximum amount of glycogen stored in the body depends on several factors, including an individual's body weight, muscle mass, and physical activity level. Generally, the maximum amount of glycogen stored in the liver is approximately 100 to 120 grams. In comparison, the maximum amount that can be stored in the muscles is approximately 300 to 400 grams. Excess glycogen is converted to and stored as fat in the body.

What Factors Increase Glycogen Storage in the Body?

Factors that can increase glycogen storage in the body include a carbohydrate diet, regular physical activity, and proper hydration. Conversely, factors that can decrease glycogen storage include a low-carbohydrate diet, prolonged fasting, and certain medical conditions that affect glycogen metabolism.

Does Glycogen Get Converted into Fat in the Body?

Glycogen is converted into fat in the body through lipogenesis. Excess glucose is converted to fatty acids and stored as triglycerides in adipose tissue when glycogen reserves are full. This conversion occurs primarily in the liver and contributes to weight gain and obesity if energy intake exceeds energy expenditure over an extended period.
Source Article Iclon Sources Source Article Arrow
Dr. Basuki Nath Bhagat from iCliniq
Dr. Basuki Nath Bhagat

Family Physician

Consult this doctor

Rate this article

Tags:

glycogen storage disease

Related topics

Liver Cirrhosis - Symptoms, Causes, Diagnosis and Treatment

Danon’s Disease - Causes, Symptoms, Diagnosis, and Treatment

Liver Cell Adenoma - Causes, Types, and Treatment

Floppy Infant Syndrome - Pathogenesis, Causes, Clinical Features, Diagnosis and Management

Hepatoblastoma - Causes, Symptoms, Diagnosis and Treatment

Benign Congenital Hypotonia - Muscle Weakness and More

Comprehensive Second Opinion

Ask your health query to a doctor online

Internal Medicine

*guaranteed answer within 4 hours

Disclaimer: No content published on this website is intended to be a substitute for professional medical diagnosis, advice or treatment by a trained physician. Seek advice from your physician or other qualified healthcare providers with questions you may have regarding your symptoms and medical condition for a complete medical diagnosis. Do not delay or disregard seeking professional medical advice because of something you have read on this website. Read our Editorial Process to know how we create content for health articles and queries.