Is your body unable to properly store and use glucose? Let's talk about Glycogen Storage Disease (GSD)!

Do you or your child feel tired all the time? Or do you sometimes suddenly feel cold, sweaty, and dizzy? Do you get tired quickly when walking or playing? Sometimes these can be due to a small problem in the way our body controls energy, that is, the way it uses sugar. Today we are going to talk about a rare disease that everyone is very important to be aware of. That is glycogen storage disease , which is also known among doctors as `(Glycogen Storage Disease)` or `(GSD)` for short.

Simply put, what does this ``(GSD)`` mean?

Okay, now let's see what this `(GSD)` is. Simply put, it's a condition where our body can't properly use or store glycogen . These are a type of metabolic disorder that is inherited, meaning that it's passed down from parent to child.

Now you may be wondering what glycogen is. Glycogen is a way for our bodies to store glucose, or sugar, from the food we eat. As you know, glucose is the main fuel that gives our bodies energy. We get this glucose from the foods we eat that contain carbohydrates. The body doesn't need all this glucose at once. So, the body stores this excess glucose in the liver and muscles as glycogen. It can be used later when we need energy.

The process by which our body makes glycogen from glucose is called glycogenesis . Similarly, when the body needs energy again, the process by which this stored glycogen is broken down and made back into glucose is called glycogenolysis . Various enzymes help in both of these processes.

Glycogen storage disease (GSD) occurs when one or more of these enzymes are missing or not working properly. This means that the body cannot use the stored glycogen for energy or maintain blood sugar levels properly. This can lead to a number of problems, including frequent low blood sugar levels (hypoglycemia) , liver damage, and muscle weakness.

Are there different types of `(GSD)`?

Yes, because our bodies use different enzymes to process glycogen, there are different types of GSD – at least 19! Doctors know a lot about some types, but they’re still learning about others. GSD mainly affects your liver or muscles. But some types can cause problems in other parts of your body, too.

Each type of GSD is caused by a deficiency of a specific enzyme involved in the storage or breakdown of glycogen. This means that the enzyme is either missing or in a reduced quantity. Doctors sometimes name these types after the name of the missing enzyme or the scientist who first discovered the GSD.

How common is glycogen storage disease?

Actually, glycogen storage disease is a very rare condition . ``(GSD)`` type I ``(GSD type I (von Gierke disease))``, which is the most common type, occurs in about one in 100,000 births. So you can see how rare this is.

What are the symptoms of GSD?

The symptoms of GSD can vary from person to person. This means that even two people with the same type of GSD can have different symptoms. GSD Type I (the most common type) usually starts showing symptoms when the baby is three to four months old . However, some of the other types may show symptoms later, sometimes even in adolescence.

The two main symptoms seen in this condition are low blood sugar (hypoglycemia) and/or fatigue during exercise, such as running or jumping (exercise intolerance).

Low blood sugar (hypoglycemia) is when your blood glucose level drops below 70 mg/dL. When this happens, you may experience symptoms such as:

• Feeling like your body is shaking.
• Sweating and feeling cold.
• Dizziness , a feeling of spinning head.
• Feeling weak and lifeless.
• Heart palpitations.
• Sometimes, unbearable hunger strikes, and some people call this ``hyperphagia''.
• Difficulty thinking, inability to concentrate.
• Feeling anxious and angry.
• Paleness of the skin (pallor).
• Sometimes, if blood sugar levels drop too low , seizures can occur.

Imagine if your little one was playing nicely and suddenly started shaking, sweating, and couldn't even speak? How scary would you feel at that moment? That's what hypoglycemia is.

In addition to this, other features such as `(GSD)` can also be seen:

• Muscle cramps or muscle weakness.
• Slow growth and poor weight gain in children.
• Enlargement of the liver (hepatomegaly).
• Low muscle tone.
• Increased cholesterol in the blood (hyperlipidemia).

What causes GSD?

The main cause of GSD is inherited genetic mutations . These genetic mutations affect the function of enzymes that are needed to store and use glycogen. A child inherits these genetic mutations from both their mother and father.

Most GSDs have an autosomal recessive inheritance pattern. This means that for a child to develop the condition, the genetic variation must be inherited from both the mother and father.

However, some types, such as GSD Group IX, have an X-linked inheritance . This means that the genetic mutation is on your X chromosome. If a male (who only has one X chromosome) has this mutation, he will develop the disease. If a female has this mutation on one X chromosome and the other X chromosome is healthy, she will usually not show symptoms, but she may be a carrier of the disease.

How do I find out if I have `(GSD)`?

To find out for sure if your child has GSD, your child's doctor will likely order several tests. Because GSD is a rare condition, it can take some time to rule out other conditions and find out exactly what type of GSD they have. These tests may include:

• Fasting blood sugar test: If your blood sugar level is low after you have eaten nothing in the morning, it could be a sign of GSD.
• Ketone blood test: When the body can't use glucose, it burns fat for energy. This produces substances called ketones. Children with GSD often experience a state of ketosis (increased ketones in the blood).
• Basic metabolic panel: This can give an idea of ​​the child's overall health.
• Lipid panel: This is also important because high cholesterol (hyperlipidemia) is common in GSD.
• Liver function tests: These can check the health of your child's liver. If there are any abnormalities, it could be a sign of GSD.
• Urinalysis: Urinalysis can check creatinine levels (which indicate kidney function) and uric acid levels. GSD often shows high uric acid levels (hyperuricemia) .
• Abdominal ultrasound: This can check if the child's liver is enlarged.
• Genetic testing: This checks for problems with genes related to various enzymes.

Although there are specific genetic tests to identify many types of GSD, sometimes your child's doctor may recommend a biopsy , which involves taking a small piece of tissue from the liver or muscle, to confirm the diagnosis.

How is GSD treated?

Unfortunately, there is no cure for glycogen storage disease. Treatment is mainly aimed at controlling symptoms. Treatment options vary depending on the type of GSD you have. Here are some examples of treatment options:

• Preventing low blood sugar: Giving uncooked cornstarch or a similar nutritional supplement at the right time and in the right amount can help keep blood sugar levels stable. Cornstarch is a complex carbohydrate that is a little harder for the body to digest. Therefore, it can control blood sugar levels for a longer period of time than the carbohydrates found in regular foods. Now there is an even better commercial product that stays in the body longer. This will also eliminate the need to get up in the middle of the night to feed your dog.
• Treating low blood sugar: If your blood sugar drops due to GSD , you should treat it immediately with carbohydrates. Otherwise, the hypoglycemia can worsen and lead to complications such as seizures and coma.
• Controlling high cholesterol: A class of drugs called statins helps control cholesterol levels.
• Controlling high uric acid levels: The drug allopurinol helps reduce the production of uric acid in the body.

Some types of GSD (for example, GSD type II) can be treated with enzyme replacement therapy (ERT) . This is usually given as an IV infusion. Research is still ongoing to see if ERT can be used for other types of GSD.

If the liver is severely damaged due to GSD, a liver transplant may be necessary.

Can glycogen storage disease be prevented?

Since glycogen storage diseases are genetic (inherited) conditions, there is nothing we can do to prevent them.

If someone in your family has GSD, and you are thinking about having a child, it is a good idea to seek genetic counseling to find out if you are also a carrier of this genetic variation.

What is the health status of someone with `(GSD)`?

In most types of GSD, early diagnosis and proper management can improve the patient's prognosis. However, some types of GSD are more difficult to manage. Your doctor can give you a better idea of ​​what to expect.

What are the possible complications of GSD?

GSD can cause a variety of complications. It depends on:

• On the `(GSD)` type.
• If the diagnosis of the disease is delayed.
• The disease, if not managed properly, will continue.

For example, some of the complications that can occur due to untreated ``(GSD)`` Category I are:

• Decreased bone density, easy fractures, and osteoporosis .
• Delayed puberty.
• Gout.
• Kidney disease.
• Pulmonary hypertension.
• Non-cancerous tumors of the liver (hepatic adenomas).
• Women with polycystic ovary syndrome (PCOS).
• Inflammation of the pancreas (Pancreatitis).
• Frequent low blood sugar levels can affect brain function.

What is the lifespan of someone with `(GSD)`?

The life expectancy of someone with glycogen storage disease (GSD) varies depending on the type, how early the disease is diagnosed, and how well it is managed. Some types can be fatal in infancy, while others can lead to a normal lifespan. Your doctor can give you the best advice on this.

When should I see a doctor?

If you or your child experience muscle weakness or persistent symptoms of low blood sugar, see a doctor immediately.

Glycogen storage diseases are rare and complex conditions. So, if possible, it's best to find a doctor who is knowledgeable about this disease and how to treat it. Your child's medical team will be with you every step of the way to help you decide on the best treatment for them.

Take-Home Message:

So, I hope you now have a better understanding of what we have been talking about, Glycogen Storage Disease (GSD). Although this is a somewhat complex topic, it is very important to remember the main points.

Remember: GSD is a group of rare, inherited diseases that cause the body to not properly use glycogen (our body's sugar store).

• Main symptoms: Frequent low blood sugar (hypoglycemia) and rapid fatigue during exercise.
• Cause: Enzyme deficiencies caused by genetic changes.
• Diagnosis: Blood tests, urine tests, ultrasound, genetic tests, and possibly a biopsy.
• Treatment: Symptomatic control is the mainstay. Diet (especially cornstarch), medication if necessary, and enzyme replacement therapy (ERT) for some types.
• The most important thing: Early diagnosis and proper management can help you live a much more normal life. If you have symptoms, don't delay seeking medical advice.

We hope this information is useful to you. Stay healthy!