|Synonyms:||Acid alpha glucosidase (GAA) deficiency
Acid maltase deficiency (AMD)
Glycogen storage disease type II
|Prevalence:||1 in 40,000|
|Age of onset:||All ages|
|ICD-10:||E74.2 Pompe disease|
|Symptoms:||Abnormal gait, Proximal limb girdle weakness, Dyspnea|
Pompe is a rare genetic disorder
Pompe is a multisystem genetic disorder characterized by the deficiency or absence of the lysosomal enzyme alpha-glucosidase (GAA). This enzyme is required to metabolize glycogen and convert it into glucose within the lysosome. It affects an estimated 1 in 40,000 worldwide, although the true prevalence is unknown.
Pompe affects 1 in 40,000.
Pompe disease is a disease continuum primarily divided into an infantile form and late-onset disease.
The disease presents within the first two or three months of life with rapidly progressive muscle weakness, hypotonia, cardiomyopathy, and feeding difficulties.
Late Onset Pompe Disease (LOPD)
Patients with Late Onset Pompe Disease (LOPD) will experience a wide range of symptoms which progress at different rates in each patient.
Patients present with signs and symptoms caused by accumulation of lysosomal glycogen, such as:
- Abnormal gait
- Proximal limb girdle weakness
- Respiratory distress/insufficiency
Possible misdiagnoses include other neuromuscular disorders such as:
- Facioscapulohumerol muscular dystrophy (FSHD)
- Limb-girdle muscular dystrophy
- Duchenne-Becker muscular dystrophy
Pompe is different from other glycogen storage diseases since patients do not typically have hypoglycemia or other metabolic decompensations.
Pompe disease should be considered when signs and symptoms suggest progressive muscular degeneration, especially of the proximal limb-girdle muscles and respiratory muscles.
If Pompe is suspected, a GAA enzyme activity assay can be performed on drawn blood. In LOPD, residual GAA enzyme activity can range from 2% to 40%. The diagnosis can then be confirmed through molecular genetic testing to detect mutations in the GAA gene or by another enzyme activity assay on a separate blood or tissue sample.
Diagnostic testing for Pompe is available
Learn more about Pompe disease
For more information on the testing, diagnosis, and treatment of Pompe disease visit Rarediseases.org
Source: Pompe Disease. National Organization for Rare Disorders. http://rarediseases.org/rare-diseases/pompe-disease/. Accessed April 25, 2016.