Classification & Types
There are forms of myotonic dystrophy. They are the adult form and the congenital form.
- This form generally becomes apparent when a person is between 10 and 30 years old. But in some cases, symptoms may appear in younger children or much later in life.
- The course of myotonic dystrophy varies widely form one person to the next, even among members of the same family. Some people with the disorder have such mild symptoms that they do not suspect anything wrong and adapt very easily. Others may be faced with a significant level of disability, requiring assistance with mobility and activities of daily living.
- In the adult form of myotonic dystrophy, muscle weakness usually starts gradually and progresses slowly. People with this form often mention stiffness as an early symptom. Disability typically occurs 15 to 20 years after the onset of the disease when the weakness affects the shoulder muscles, thighs and hips, though many people with myotonic dystrophy live their entire lives without any detectable symptoms.
- The congenital form of myotonic dystrophy, as its name implies, is always present at birth. Affected infants are profoundly weak and have many difficulties. Frequently, there are problems associated with breathing, sucking and feeding.
- The babies are extremely hypotonic (decreased muscle tone) at birth, and as a result they appear floppy. Some babies die within a few hours or days of birth.
- Infants with congenital myotonic dystrophy have weakness in virtually all muscles, including the respiratory and facial muscles. If the infant survives the newborn period, a gradual improvement is generally noted in his/her respiratory function and ability to swallow. As they grow older, children are slow in developing language, making it difficult or impossible for them to live totally independent lives as adults.