Glycogen storage disease type III
What are the main signs and symptoms of glycogen storage disease type 3?
Glycogen storage disease type III (GSD III) typically presents with liver problems first. In babies, the liver may be enlarged and lab studies to look at liver function may be abnormal. If GSD III is not treated, babies can have low blood sugar, enlarged liver, muscle weakness, delayed growth and development, sleepiness and irritability. If a baby is not treated properly when symptoms develop, these symptoms can progress to seizures, coma or even death. Symptoms usually improve with frequent feeding (every 3-4 hours) and avoidance of becoming ill. When a person with GSD III becomes ill, close medical monitoring is needed to ensure that symptoms do not get worse and that the person is safe.
During adolescence, the liver tends to shrink and liver problems may become milder. Many people with GSD IIIa subtype, may also experience muscle weakness in adolescence and adulthood. Because the heart is a muscle, GSD III can also result in weakness of the heart muscle (hypertrophic cardiomyopathy) that may need to be followed closely by a specialist.
If your child with GSD III is experiencing any symptoms of low blood sugar or is sick with a fever, vomiting or diarrhea, consult with your main doctor or genetic/metabolic doctor. It may be important for your child to get emergency treatment.