Duchenne’s Muscular Dystrophy

Muscular dystrophy is a general term used for a group of genetic diseases characterized by weakness and degeneration of the skeletal muscles and in some cases, of the heart muscles and other involuntary muscles. Some of the common diseases in this group are: Mytonic dystrophy, amyotrophic lateral sclerosis, facioscapulohumeral, limb-girdle, and Duchenne’s. Duchenne is the most common form of muscular dystrophy in children and Mytonic is the most widespread among adults. Muscular dystrophy can develop at any age.

As of today, there is no specific cure for these diseases although physiotherapy helps prevent muscle degeneration and helps the patient maintain his mobility inside and out of the house. In some serious cases, orthopedic surgery is needed to prevent muscle deterioration and deformities of the joints. While drug treatments usually alleviate the symptoms, there is no known drug capable of healing the illness. Some of these diseases develop at a very gradual pace and exhibit only light symptoms, allowing the patients to conduct regular lives. On the other end of the spectrum are those diseases that can cause death within a relatively short time.

One genre of muscular dystrophy was named after Guillaume Duchenne, a French doctor from the nineteenth century who was the first to categorize this specific disease. Duchenne’s muscular dystrophy, which affects mostly males, is one of the most common muscular diseases. The disease causes the body to atrophy gradually, starting from early childhood.

In June, 1986, Lewis Kankl and his student discovered the gene responsible for causing the disease, thereby making it possible to detect the illness in the prenatal period.

Males are much more susceptible to be afflicted with Duchenne’s since the disease is caused by an irregularity of the x chromosome. Since a female’s genetic composition is xx, she has an extra x to stand in for a defective x whereas a male’s genetic composition is xy and therefore, if the x chromosome is defective, he has no alternate x for backup. Thus, a boy born to a mother who is a carrier has a 50% chance of being afflicted with Duchenne’s.

Since women have two x chromosomes, they are generally not affected by this disease, but they may be carriers. And those who are carriers have a chance of giving birth to sons with this defect.

Researchers have been successful in identifying the protein complex that’s produced by healthy genes and is responsible for maintaining muscle mass and potency. The protein, named Dystrophin for the disease that it prevents, is absent in the muscle cells of a patient with Duchenne’s. And although muscle tissues do repair themselves, even in patients with Duchenne’s, the degeneration far outpaces the rate of repair. As a result, muscle mass is severely diminished and replaced by fibrous tissue and fat. 

Diagnosis

A diagnosis of Duchenne’s muscular dystrophy is based on the rapid degeneration of muscles. Signs of this disease first surface between age two and three years, a stage marked by a significant amount of walking and ascending stairs. At the beginning phase of the disease, the child has difficulty climbing stairs and may sometimes complain of pain in the shin muscles.

A conclusive diagnosis is usually made after age three. The disease manifests itself in weakness in the pelvic muscles and lower body, which may cause the child to adopt a duck-like waddle. The child may also have difficulty getting up from a sitting position and ascending stairs. As time goes on, the child’s mobility gets more and more stilted. The acute lack of muscle stamina inevitably diminishes other bodily functions and a lack of physical activity usually leads to the patient being overweight, which only exacerbates the situation.

The mortality age for Duchenne’s patients is generally young, approximately in their second or third decade of life. Death usually occurs as a result of the collapse of the cardiac-pulmonary system.  

Symptoms

Symptoms vary according to the different types of muscular dystrophies, but they generally include: muscle weakness that causes frequent falls, impaired muscle activity, difficulty walking, difficulty controlling saliva, and ptosis (drooping of the eyelid).

In addition to widespread loss of muscle mass, additional factors that are examined when suspecting muscular dystrophy are: fat deposits and fibrous tissues in the place of muscle – something easily detected in the tibia (shin) muscles as the leg takes on a bloated look. Muscular dystrophy can sometimes affect the heart muscles.

Treatment

To date, there is no known cure for Duchenne’s muscular dystrophy. The standard treatment for the disease targets only the symptoms and helps improve the patient’s quality of life. The goal is to encourage physical activity over a sedentary lifestyle in order to avoid a situation where the patient will become bedridden. Physical inactivity can drastically exacerbate muscular degeneration. Physical therapy helps hinder the progression of the disease and preserves as much muscle mass as possible. 

Complications

• Structural distortions
• Permanent limp and diminished mobility
• Mental impairment (usually minimal)
• Frequent pneumonia or respiratory problems
• Cardiomyopathy (disease of the heart muscles)/ Congestive heart failure/ Arrhythmias (irregular heart beat)

Entitlements

Handicapped children are entitled to receive benefits from Bituach Leumi; it is important to utilize these rights so that children with Duchenne’s can receive proper physiotherapy and hydrotherapy, both of which are crucial to preserving stamina and muscle mass. Proper equipment such as suitable walkers, wheelchairs etc. is needed for both school and home. Children with Duchenne’s need neurological, orthopedic and cardiopulmonary follow-up care on a regular basis.