MUSCULAR DYSTROPHY
Muscular Dystrophy
Muscular distrophies include many inherited disorders such as:
- Becker's muscular dystrophy
- Duchenne muscular dystrophy
- facioscapulohumeral muscular dystrophy
- limb-girdle muscular dystrophy
- Emery-Dreifuss muscular dystrophy
- myotonic dystrophy
- myotonia congenita
Disorders are distinguished by the type of inheritance (sex-linked, dominant genes , or recessive gene, and so on), the age when symptoms appear, and the types of symptoms that develop. Because these are inherited disorders, risks include a family history of muscular dystrophy.
Lambert-Eaton syndrome and myasthenia gravis have symptoms
that may be similar to early stages of some types of muscular
dystrophies.
What are the Symptoms of Muscular Dystrophy?
Symptoms vary with the different types of muscular dystrophy. Certain types, such as Duchenne dystrophy, are ultimately fatal while other types have associated muscle weakness but cause little disability.
Symptoms usually include:
-
muscle weakness- progressive
-
frequent falls
-
delayed development of muscle skills
-
problems walking
-
difficulty using a muscle group (the specific muscle affected depends on the type of MD)
-
eyelid drooping (ptosis)
-
drooling
-
intellectual retardation
Symptoms that are only present in some
types of MD include:
- hypotonia
- skeletal deformities
- muscle deformities
- contracture deformities (clubfoot, clawhand or others)
- scoliosis
- enlargement of the calve muscles (pseudohypertrophy)
How is Muscular Dystrophy Diagnosed?
Examination and history help to distinguish the type of MD. Specific muscle groups are affected by different types of MD. Often, there is a loss of muscle mass (wasting), which may be disguised in some types of muscular dystrophy by an accumulation of fat and connective tissue making the muscle appear larger (pseudohypertrophy). Muscle contractures are common. Shortening of the muscle fibers, fibrosis of the connective tissue and scarring slowly destroy muscle function. Some types of MD involve the heart muscle, causing cardiomyopathy or arrhythmias.
- A muscle biopsy may be the primary test used to confirm
the diagnosis.
- In some cases a DNA test from the blood may be sufficient.
- A serum CPK may be elevated.
- An EMG (electromyography) may confirm that weakness is
caused by destruction of muscle tissue rather than damage
to nerves.
- An ECG (electrocardiography) to monotor changes in cardiac status.
This disease may also alter the results
of the following tests:
- myoglobin - urine
- myoglobin - serum
- LDH isoenzymes
- LDH
- creatinine - urine
- creatinine
- CPK isoenzymes
- AST
- aldolase
What is the Treatment for Muscular Dystrophy?
There are no known cures for the various muscular dystrophies.
Treatment is aimed at controlling symptoms to maximize the quality
of life. Activity is encouraged to the degree tolerated. Inactivity
(such as bedrest) can worsen the muscle disease. Physical therapy
may be helpful to maintain muscle strength and functioning.
Orthopedic appliances such as braces and wheelchairs may improve
mobility and self-care abilities. In some cases, surgery of
the spine or lower extremities may help improve function and
prevent or slow deterioration.