Typically, symptomatology becomes apparent in
children at the age of 1 to 5 years, who present with a protuberant abdomen, growth
and mild motor retardation, mild fasting hypoglycemia, and hypotonia. Some
patients are asymptomatic, but physical abdominal examination reveals
hepatomegaly, which may be massive. Severe hypoglycemia is rare. Mild
cardiomyopathy may occur in some patients.