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Start free with EleplanGlycogen storage disease due to acid maltase deficiency, late-onset
ORPHA:420429Clinical subtype
Also called Alpha-1,4-glucosidase acid deficiency, late-onset · GSD due to acid maltase deficiency, late-onset · GSD type 2, late-onset · GSD type II, late-onset · Glycogen storage disease type 2, late-onset · Glycogen storage disease type II, late-onset · Glycogenosis type 2, late-onset · Glycogenosis type II, late-onset · Pompe disease, late-onset
What it is
A rare form of glycogen storage disease due to acid maltase deficiency characterized by excessive accumulation of glycogen in lysosomes most notably in skeletal muscle, leading to slowly progressive muscle weakness with walking disability and reduced respiratory function. The late-onset form includes all cases in which hypertrophic cardiomyopathy did not manifest or was not diagnosed at or under the age of 1 year, as well as all cases with symptom onset above the age of 1 year.
Key facts
- Prevalence
- 1-9 / 100 000 (at birth)
- Age of onset
- Adolescent, Adult
- Inheritance
- Autosomal recessive
- Classified as
- Clinical subtype
Prevalence figures describe populations, not individuals, and are often estimates from a single study. Where the figure is an incidence or a birth prevalence, it says so.
Gene
ICD-10 codes
ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.
Related health topics
Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
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