Glycogen storage disease (GSD) is a rare condition that changes the way the body uses and stores glycogen, a form of sugar or glucose.
Glycogen is a main source of energy for the body. Glycogen is stored in the liver. When the body needs more energy, certain proteins called enzymes break down glycogen into glucose. They send the glucose out into the body.
When someone has GSD, they are missing one of the enzymes that breaks down glycogen. When an enzyme is missing, glycogen can build up in the liver. Or glycogen may not form properly. This can cause problems in the liver or muscles, or other parts of the body.
GSD is passed down from parents to children (is hereditary). It is most often seen in babies or young children. But some forms of GSD may appear in adults.
Types of GSD are grouped by the enzyme that is missing in each one. Each GSD has its own symptoms and needs different treatment.
There are several types of GSD, but the most common types are types I, III, and IV. These types are also known by other names:
Glycogen storage disease is passed down from parents to children (hereditary).
It happens because both parents have an abnormal gene (gene mutation) that affects a specific way that glycogen is stored or used. Most GSDs occur because both parents pass on the same abnormal gene to their children.
In most cases parents don’t show any symptoms of the disease.
With many types of GSD, symptoms first appear in babies or in very young children. Symptoms will vary based on the type of GSD a child has, and on which enzyme he or she is missing.
Because GSD most often affects the muscles and the liver, those areas show the most symptoms.
General symptoms of GSD may include:
Symptoms for babies may include:
The symptoms of GSD may look like other health problems. Always see your child’s healthcare provider to be sure.
Some types of GSD can appear in adults. See your healthcare provider if you think you may have GSD.
Your child’s healthcare provider will ask about your child’s symptoms and past health. The provider will do a physical exam to check for symptoms such as an enlarged liver or weak muscles.
Your child’s provider may do a few blood tests. He or she may also take a small tissue sample (biopsy) of your child’s liver or muscle. The sample will be taken to a lab. It will be tested to see how much of a certain enzyme is in that part of the body.
If you are pregnant and concerned about GSD, your healthcare provider may do some tests before your baby is born (prenatal tests) to check for GSD.
Treatment will vary depending on what type of GSD your child has.
For types I, III, and IV, your child’s healthcare provider may suggest a special diet to help control symptoms. Your child may also have to take certain medicines.
For other types of GSD, your child may need to limit exercise to avoid muscle cramps. He or she may need to have a medical treatment to replace the enzyme that is missing (enzyme replacement therapy).
Glycogen buildup can hurt the liver and muscles. This can create other problems if your child has certain types of GSD such as:
There is no way to prevent glycogen storage disease. But early treatment can help control symptoms once a child has GSD.
If you or your partner have GSD, or a family history of this disease, see a genetic counselor before you get pregnant. He or she can find out your chances of having a child with GSD.
A child with GSD may have special needs. Be sure that your child gets regular medical care. It is important that his or her healthcare provider checks your child’s condition. Regular medical visits will also help you keep up with new treatment options.
Online or in-person support groups may also be helpful for you and your family.
Many forms of glycogen storage disease appear in babies and young children.
Call your healthcare provider if your baby’s behavior changes after you stop night feedings.
Talk with your healthcare provider if your child:
Teens and adults should watch for the following symptoms when they exercise:
Tips to help you get the most from a visit to your child’s healthcare provider:
The University of Chicago Medicine
5841 S. Maryland Avenue
Chicago, IL 60637 | 773-702-1000
Appointments: Call UCM Connect at 1-888-824-0200