muscle diseases

Question 1

What is pompe disease?

Answer 1

Pompe disease (also known as acid-maltase disease and glycogen storage disease II) is a rare genetic disorder that causes progressive weakness to the heart and skeletal muscles.It is caused by mutations in a gene that makes an enzyme called acid alpha-glucosidase (GAA), which the body uses to break down glycogen, a stored form of sugar used for energy. The enzyme performs its function in intracellular compartments called lysosomes, which function as cellular clearinghouses.Lysosomes ingest multiple substances including glycogen, which is converted by the GAA into glucose, a sugar that fuels muscles.
In Pompe disease, mutations in the GAA gene reduce or completely eliminate this essential enzyme, which causes buildup that damages the muscles of the skeletal muscles and heart most seriously.The severity of the disease and the age of onset, which varies widely, are related to the degree of enzyme deficiency.

Question 2

What are the two main types of pompe disease?

Answer 2

There are two forms of Pompe disease:

Early onset (infantile form) is caused bythe complete or near complete deficiency of GAA.Symptoms begin in the first months of life, with feeding problems, poor weight gain, trouble breathing, muscle weakness, enlarged heart, floppiness, and head lag. Many infants with Pompe disease also have enlarged tongues. Without enzyme replacement therapy, most babies die from cardiac or respiratory complications before their first birthday.

Late onset (juvenile/adult)results from partial deficiency of GAA and can begin as early as the first decade of childhood or well into adulthood. Muscle weakness progresses to death from respiratory failure afterseveral years. The heart is usually not involved.

Question 3

What is the treatment for Pompe disease?

Answer 3

Enzyme replacement therapy can help improve muscle tone and reduce glycogen storage in individuals with Pompe disease. The following drugs have been approved:

Alglucosidase alfa (Myozyme©) to treat infantile-onset Pompe disease

Lumizyme© to treat individuals of all ages with Pompe disease

Avalglucosidare alfa-ngpt (Nexviazyme©) for individuals age 1 and older with late-onset Pompe disease