Types of GSD

Type 1a

Deficient Enzyme

Glucose-6-phosphatase (G6Pase)

Gene

G6PC

Inheritance

Autosomal recessive

Organs Affected

Liver, kidneys, intestines

Overview

GSD Type 1a is caused by a deficiency of the enzyme glucose-6-phosphatase. This enzyme is needed to release glucose from the liver into the bloodstream. Without it, glycogen and fat accumulate in the liver and kidneys, causing them to enlarge. The primary symptom is severe hypoglycemia (low blood sugar), which can occur within hours of eating.

Signs & Symptoms

Severe hypoglycemia
Enlarged liver (hepatomegaly) and kidneys
Growth retardation
Lactic acidosis
Hyperlipidemia
Hyperuricemia (gout)
Osteoporosis
Possible liver adenomas

Treatment

Frequent feedings and/or continuous overnight cornstarch or glucose feeds to maintain blood glucose levels. Uncooked cornstarch (UCCS) is a mainstay of treatment. Dietary management with a low-fat, low-fructose, low-galactose diet.