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ORPHA:34587Disease
Also called GSD due to LAMP-2 deficiency · GSD, type 2B · GSD, type IIb · Glycogen storage disease due to LAMP-2 deficiency · Glycogen storage disease, type 2B · Glycogen storage disease, type IIb · Glycogenosis due to LAMP-2 deficiency · Lysosomal glycogen storage disease with normal acid maltase activity
What it is
A rare X-linked genetic condition due to deficiency of the lysosomal-associated membrane protein 2 (LAMP2) characterized by severe cardiomyopathy and variable degrees of muscle weakness, frequently associated with intellectual deficits (in males).
Key facts
- Prevalence
- <1 / 1 000 000
- Age of onset
- Childhood
- Inheritance
- X-linked dominant
- Classified as
- Disease
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.
Signs and symptoms
Very common80–99%
6Common30–79%
15- Blurred vision
- Chest pain
- Cough
- Dyspnea
- Elevated circulating creatine kinase concentration
- Elevated circulating hepatic transaminase concentration
- Intellectual disability
- Muscle weakness
- Myopia
- Progressive proximal muscle weakness
- Reduced visual acuity
- Skeletal myopathy
- Specific learning disability
- Wheezing
- Wolff-Parkinson-White syndrome
Sometimes5–29%
9- Anxiety
- Attention deficit hyperactivity disorder
- Atypical behavior
- Depression
- Hepatomegaly
- Motor delay
- Nyctalopia
- Photophobia
and 1 more in this range
These ranges are how often a sign appears across everyone diagnosed, not a prediction for one person — most people have some of these and not others. Orphanet also records findings that are specifically absent in this disease; those are in the data but not listed here.
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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