glycogenosis type 3
MIM.232400 1p21
Autosomal recessive metabolic disease.
Synopsis
short stature
growth retardation
midface hypoplasia
deep-set eyes
depressed nasal bridge
broad upturned nasal tip
bow-shaped lips
thin vermillion border
cardiomyopathy
ventricular hypertrophy on ECG
hepatic anomalies
- hepatomegaly
- hepatic fibrosis
- glycogen hepatocytic overload
- rarefied cytoplasm
- pyknotic anc eccentrically-located nuclei
- mosaic appearance
- hepatocytic steaosis
- cirrhosis (adults)
-
hepatic tumors
- hepatic adenoma
- hepatocellualr carcinoma (adults)
muscle weakness (increases with age)
distal muscle wasting
myopathy
hypoglycemia
LABORATORY ABNORMALITIES
Amylo-1,6-glucosidase deficiency
Hypoglycemia
Hyperlipidemia
Normal blood lactate
Normal uric acid
Elevated transaminases
Subtypes
GSD 3a (GSD type IIIa): both liver and muscle involvement
GSD 3b (GSD type IIIb): liver involvement only (15% of all cases)
Etiology
germline mutations in the amylo-1,6-glucosidase, 4-alpha-glucoanotransferase gene (AGL) (MIM.232400)