Definitions

Muscular dystrophies

Muscular dystrophies are diseases of the muscle characterized by muscle fiber degeneration and associated progressive muscle weakness. Muscular dystrophies are an inherited group of disorders, and include Duchenne and Becker, Emery Driefuss, limb-girdle, facioscapulohumeral, myotonic, and distal types.

Dystrophinopathies

Dystrophinopathies are characterized by mutations in the dystrophin gene, and (depending on mutation type and location) cause a range of muscle diseases.

  • The most severe presentation is Duchenne muscular dystrophy, followed by Becker muscular dystrophy.
  • Duchenne-related dilated cardiomyopathy is characterized by left ventricular dilation and congestive heart failure.
  • Less severe dystrophinopathies include isolated quadriceps myopathy and muscle cramps with myoglobinuria.