Summary about Disease
Pompe disease is a rare, inherited disorder caused by a deficiency or absence of the enzyme acid alpha-glucosidase (GAA). This enzyme is essential for breaking down glycogen, a complex sugar stored in the body for energy. Without enough GAA, glycogen builds up in cells, particularly in muscle cells, leading to progressive muscle weakness and organ damage. Pompe disease is classified as a lysosomal storage disorder. There are two main forms: infantile-onset (typically more severe) and late-onset.
Symptoms
Infantile-onset Pompe disease:
Muscle weakness (hypotonia)
Enlarged heart (cardiomyopathy)
Feeding difficulties
Breathing problems
Liver enlargement
Failure to thrive
Developmental delays
Late-onset Pompe disease:
Progressive muscle weakness, particularly in the legs and trunk
Breathing difficulties
Fatigue
Exercise intolerance
Difficulty rising from a seated or lying position
Back pain
Frequent respiratory infections
Causes
Pompe disease is caused by mutations in the GAA gene. This gene provides instructions for making the acid alpha-glucosidase enzyme. The disease is inherited in an autosomal recessive pattern, meaning that both parents must carry a copy of the mutated gene for a child to be affected. If both parents are carriers, there is a 25% chance with each pregnancy that the child will inherit both mutated genes and develop Pompe disease. There is a 50% chance that the child will be a carrier (inherit one mutated gene and one normal gene) and a 25% chance that the child will inherit two normal genes and not be affected.
Medicine Used
The primary treatment for Pompe disease is enzyme replacement therapy (ERT). This involves intravenous infusions of a synthetic form of the GAA enzyme. Two ERT medications are currently available:
Alglucosidase alfa (Myozyme): Approved for both infantile-onset and late-onset Pompe disease.
Avalglucosidase alfa-ngpt (Nexviazyme): Approved for late-onset Pompe disease. Supportive therapies, such as physical therapy, respiratory support, and nutritional support, are also important in managing the symptoms and complications of Pompe disease.
Is Communicable
No, Pompe disease is not communicable. It is a genetic disorder and cannot be spread from person to person through any infectious route.
Precautions
There are no specific precautions to prevent acquiring Pompe disease, as it is a genetic condition. For individuals with Pompe disease, precautions focus on managing the symptoms and preventing complications:
Regular monitoring of heart and respiratory function.
Physical therapy and exercise to maintain muscle strength and flexibility.
Respiratory support, such as mechanical ventilation, if needed.
Nutritional support to ensure adequate caloric intake and prevent malnutrition.
Vaccinations to prevent respiratory infections.
Avoiding activities that overexert the muscles.
Careful monitoring and management of any other health conditions.
How long does an outbreak last?
Pompe disease is not an infectious disease, so the term "outbreak" is not applicable. The symptoms of Pompe disease are chronic and progressive, meaning they develop gradually and worsen over time. There is no specific "outbreak" period.
How is it diagnosed?
Pompe disease is diagnosed through a combination of clinical evaluation and laboratory testing:
Clinical evaluation: A physician will assess the patient's symptoms, medical history, and family history.
Enzyme assay: A blood or tissue sample is tested to measure the level of acid alpha-glucosidase (GAA) enzyme activity. Low or absent GAA activity is indicative of Pompe disease.
Genetic testing: A blood sample is tested to identify mutations in the GAA gene.
Muscle biopsy: In some cases, a muscle biopsy may be performed to examine muscle tissue for glycogen accumulation.
Newborn screening: In some regions, Pompe disease is included in newborn screening programs.
Timeline of Symptoms
The timeline of symptoms varies depending on the type of Pompe disease:
Infantile-onset: Symptoms typically appear within the first few months of life. Without treatment, most infants with classic infantile-onset Pompe disease die within the first year of life due to heart and respiratory failure.
Late-onset: Symptoms can appear anytime from late childhood to adulthood. The progression of late-onset Pompe disease is more variable. Some individuals may experience a slow and gradual decline in muscle strength, while others may experience a more rapid progression. Life expectancy is also variable, depending on the severity of the disease and the effectiveness of treatment.
Important Considerations
Early diagnosis is crucial: Early diagnosis and treatment with enzyme replacement therapy can significantly improve the outcome for individuals with Pompe disease, especially in infantile-onset cases.
Genetic counseling: Genetic counseling is recommended for families with a history of Pompe disease to assess their risk of having affected children.
Long-term management: Pompe disease requires lifelong management, including regular monitoring, enzyme replacement therapy, and supportive care.
Research: Ongoing research is focused on developing new and improved treatments for Pompe disease, including gene therapy.
Support groups: Support groups can provide valuable resources and emotional support for individuals with Pompe disease and their families.