Medicina

Muscular Dystrophy

What is Muscular Dystrophy?
The muscular dystrophies (MD) are a group of more than 30 genetic diseases characterized by progressive weakness and degeneration of the skeletal muscles that control movement. Some forms of MD are seen in infancy or childhood, while others may not appear until middle age or later. The disorders differ in terms of the distribution and extent ofmuscle weakness (some forms of MD also affect cardiac muscle), age of onset, rate of progression, and pattern of inheritance.
Duchenne MD is the most common form of MD and primarily affects boys. It is caused by the absence of dystrophin, a protein involved in maintaining the integrity of muscle. Onset is between 3 and 5 years and the disorder progresses rapidly. Most boys are unable to walk byage 12, and later need a respirator to breathe. Girls in these families have a 50 percent chance of inheriting and passing the defective gene to their children. Boys with Becker MD (very similar to but less severe than Duchenne MD) have faulty or not enough dystrophin.
Facioscapulohumeral MD usually begins in the teenage years. It causes progressive weakness in muscles of the face, arms, legs, andaround the shoulders and chest. It progresses slowly and can vary in symptoms from mild to disabling.
Myotonic MD is the disorder's most common adult form and is typified by prolonged muscle spasms, cataracts, cardiac abnormalities, and endocrine disturbances. Individuals with myotonic MD have long, thin faces, drooping eyelids, and a swan-like neck.
¿Qué es la distrofia muscular?
Themuscular dystrophies (MD) are a group of more than 30 genetic diseases characterized by progressive weakness and degeneration of the skeletal muscles that control movement. Las distrofias musculares (DM) son un grupo de más de 30 enfermedades genéticas caracterizadas por debilidad progresiva y degeneración de los músculos esqueléticos que controlan el movimiento. Some forms of MD are seen in infancy orchildhood, while others may not appear until middle age or later. Algunas formas de MD se ven en la infancia o la niñez, mientras que otros pueden no aparecer hasta la mediana edad o después. The disorders differ in terms of the distribution and extent of muscle weakness (some forms of MD also affect cardiac muscle), age of onset, rate of progression, and pattern of inheritance. Los trastornosdifieren en cuanto a la distribución y el grado de debilidad muscular (algunas formas de distrofia muscular también afectan el músculo cardíaco), edad de inicio, velocidad de progresión, y el patrón de herencia.
Duchenne MD is the most common form of MD and primarily affects boys. Distrofia muscular de Duchenne es la forma más común de distrofia muscular y afecta principalmente a niños. It is causedby the absence of dystrophin, a protein involved in maintaining the integrity of muscle. Es causada por la ausencia de distrofina, una proteína implicada en mantener la integridad del músculo. Onset is between 3 and 5 years and the disorder progresses rapidly. El inicio es entre 3 y 5 años y la enfermedad progresa rápidamente. Most boys are unable to walk by age 12, and later need a respirator tobreathe. La mayoría de los niños no pueden caminar por los 12 años, y más tarde necesitar un respirador para respirar. Girls in these families have a 50 percent chance of inheriting and passing the defective gene to their children. Las niñas de estas familias tienen una probabilidad del 50 por ciento de heredar y transmitir el gen defectuoso a sus hijos. Boys with Becker MD (very similar to butless severe than Duchenne MD) have faulty or not enough dystrophin. Los niños con distrofia muscular de Becker (muy similar pero menos grave que la distrofia muscular de Duchenne) no lo suficiente distrofina o defectuoso.
Facioscapulohumeral MD usually begins in the teenage years. DM facioescapulohumeral por lo general comienza en la adolescencia. It causes progressive weakness in muscles of...