About GSD

Glycogen Storage Disease Type 1a (glucose-6-phosphatase deficiency, von Gierkes disease,) is a rare genetic metabolic disorder centered in the liver. In children afflicted with GSD1, a specific enzyme that breaks down certain carbohydrates, including glycogen (a stored form of sugar,) is either missing or not functioning properly. Because of the missing /impaired enzyme, the body cannot create glucose from glycogen and it is difficult to maintain normal blood sugar levels between meals without constant feedings. Glucose is the essential energy source for every cell in the body. Dangerous by-products such as lactate, uric acids and triglycerides in combination with low blood sugar leads to numerous complications in GSD1 including impaired breathing, seizures, coma and death if a very strict dietary regimen is not followed.

Children with this disease appear normal at birth, however, the child will begin to exhibit symptoms such as low blood sugar, an enlarged liver, failure to thrive, developmental delay, elevated lactate and uric acid levels in the blood and urine, and seizures. Because of GSD1's rarity, these symptoms are often not fully recognized and can lead to misdiagnosis. This will eventually lead to a crisis situation within the first three to four months of life. It is not known how many children die without ever having been properly diagnosed. Diagnosis is confirmed through a liver biopsy or DNA testing. After GSD1 is identified, the only way to minimize symptoms is to closely monitor blood sugar levels and to adjust diet accordingly. Currently there is no cure for GSD1.

The management of GSD1 is lifelong. GSD not only affects the child, but also deeply affects the parents and family of the child born with this disease. Diet is the cornerstone of treatment and many types of foods are restricted, severely limiting dietary options. GSD1 children should minimize foods containing sucrose (table sugar,) fructose (sugar found in fruits,) and lactose and galactose (sugars found in milk products) because these sugars end up as glycogen trapped in the liver. They also must be fed every one to four hours in order to maintain blood glucose at an appropriate level. Because this can often be very difficult for the child to tolerate and because missing a meal or a feeding time can have catastrophic effects, most have a gastric or naso-gastric tube placed. In infancy, the tube is critical for frequent feeds during the day and for using a continuous feeding pump at night. This alternative route of ingestion will also help during times of normal childhood illnesses when hypoglycemia and acidosis can occur more often. A consequence of having to eat so frequently is that GSD children often have problems ingesting food by mouth. They must undergo intensive therapy to relearn sucking, swallowing and even speech patterns.

Researchers have identified the chromosomal defects of this disease. With the combination of advances in gene therapy, more public awareness, and financial support GSD1 can be cured in the near future.

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Frequently asked questions.…

How do you get GSD1? GSD1 is a genetic disorder. Both parents have to be carriers of this disease in order to pass it onto their children. GSD1 has been found in almost every culture around the world.  It is estimated that 1 in 60 Ashkenazi Jews are carriers of this disease. You can take a blood test to find out if you may be a carrier.

When and how are children diagnosed? Children with GSD1 are usually diagnosed anywhere between 4 – 10 months of age, with a DNA blood test or liver biopsy. Symptoms at the time of diagnosis may include: enlarged livers, failure to thrive, hypoglycemia, developmental delays, respiratory distress, acidotic shock, and seizures. There are many physicians even today, who are unfamiliar with the signs and symptoms which can point to GSD1.

Will the child ever grow out of it? No, a child born with GSD will have it for life, until a cure can be found.

Why do people with GSD1 need to eat so often? Children with GSD1 cannot release stored sugars when blood glucose levels start to fall and therefore must eat at regular intervals around the clock, (every 1-3 hours during the day and 3-4 hours at night) to avoid serious side effects.

Is there any medication to take? At this time, there is no medication for GSD1, only large doses of Argo cornstarch, which is a complex carbohydrate that can break down slower than other carbohydrates, thus allowing for more time in between feedings.

Why do most children with GSD have a feeding tube? The feeding tube assures that caregivers will be able to have a way to get food and cornstarch into the child. It also allows the child (though not the parents) to sleep during the nighttime feedings. It can also help to maintain blood glucose levels during times of illness.

Why are there oral issues in patients with GSD? As a result of the continuous feeding schedule, GSD children lack natural oral functionality and curiosity. Many must undergo intensive therapy to learn or relearn reflexes that we take for granted such as sucking, swallowing and even speech.

There’s only cornstarch between you and disaster The biggest concern about GSD1 is that at anytime, the disease can go from a well controlled situation to complete disaster in a matter of minutes – either by being late for a feeding or because the child may have a stomach virus, which can affect the blood glucose levels almost immediately. The health of a GSD1 patient is only as good as his/her last feeding.

Are there dietary restrictions in GSD1? People with GSD1 should avoid sugars such as sucrose (table sugar), fructose (sugar found in fruits), lactose and galactose (sugars found in milk). This is because the liver is unable to break down these sugars, which get stored and trapped in the liver as glycogen. Dangerous byproducts such as uric acid, cholesterol and lipids can build-up so GSD1 kids should eat foods containing pure glucose or dextrose and foods high in complex carbohydrates such as potatoes and rice.

How can you help your friends who have a child with GSD1? You can help by understanding more about the disease and by learning how to help care for their child – perhaps learning how and when to feed a GSD child and what to do in an emergency.

Will there be a cure for GSD1? There are now a number of talented researchers around the world working hard and making amazing progress towards finding a cure for GSD1. We at The Children’s Fund are confident that there will be a cure for GSD1 in the near future.

What can you do to help? You can join our organization’s commitment to funding research so that children born with GSD1 will benefit from early detection, treatment and an eventual cure. Please consider organizing a fundraiser, volunteering on an existing project or simply make a donation. There is strength in numbers and we welcome your help and support.