"My child may have Duchenne muscular dystrophy, and I want to learn more."

Duchenne is a type of muscular dystrophy that causes muscles to weaken as a result of the absence of dystrophin, the protein that keeps muscles healthy and functioning properly. The weakening of the muscles gets worse over time and leads to difficulty in physical function, such as standing up, walking, and in later stages, breathing. As these functions become more difficult, it becomes harder for the patient to perform daily activities, and that can lead to a loss of independence.

Duchenne mainly affects boys. However, girls can be affected also, but when they are they usually do not experience the full effects of the disease in the same way boys do.

Signs of the disease start at a young age and may be noticed when a child has difficulty standing up, climbing, or running.

Duchenne affects about 1 of every 3,600 to 6,000 male births worldwide each year.

Although children with Duchenne appear healthy when they are born, reaching developmental milestones, such as sitting, walking, and talking, is delayed compared with children who do not have Duchenne. Typically between the ages of 2 and 5, children with Duchenne start to show more obvious signs and symptoms of the disease.

Signs and symptoms of Duchenne can include:

  • Frequent falling
  • Calf enlargement
  • Learning and behavior problems, including poor attention and memory skills
  • Delayed speech development
  • Delayed motor development
  • Unusual waddling gait
    • That can include swaying while walking, walking with the feet far apart, and walking on the toes
  • Difficulty keeping up with friends during play and physical activities
  • Weakened reflexes
  • Breathing difficulties
  • Use of Gowers maneuver to get up from the floor or from a chair

Because their hip and thigh muscles are weak, children with Duchenne may use a technique called Gowers maneuver when getting up from the floor. This maneuver allows them to stand up by using their hands and arms to “walk” up their lower limbs (shins, knees, and thighs) until they reach a standing position.

Gowers maneuver
Gowers maneuver
Gowers maneuver
Gowers maneuver

Used courtesy of Custom Learning Designs, Inc.

If you notice any of the above signs or symptoms in your child, it is important to speak to your child’s doctor right away. He or she can help your child receive a correct diagnosis.

Duchenne causes muscle weakness, which worsens over time, resulting in increasing difficulty in performing everyday tasks and functions, such as walking, standing, and breathing–all of which can lead to an eventual loss of independence.

Although the progression and severity of symptoms of Duchenne differ for every child, there are several distinct phases of the disease. Those phases may be referred to by different names by doctors, publications, and websites.

As the symptoms progress over time, so do the care needs of someone living with Duchenne. Although there is no cure for Duchenne, disease management strategies exist that can help maintain muscle function and slow the progression of the disease. Those interventions may help improve a patient’s quality of life.

Use the arrows to learn about the different phases of Duchenne.

Duchenne is caused by a mutation, defect, or flaw in the gene that makes dystrophin, the protein that keeps muscles healthy and functioning properly.

There are several types of dystrophin gene mutations that cause Duchenne:

  • Deletion mutationsThese happen when one or more exons, the protein-coding portions of the gene, are missing from the dystrophin gene. Nonfunctional proteins result from these mutations
  • Duplication mutationsThese happen when one or more exons are copied in the dystrophin gene. Nonfunctional proteins result from mutations
  • Small mutationsVarious kinds of small mutations result in nonfunctional proteins. About half of small mutations are nonsense mutations. Nonsense mutations occur when the dystrophin gene produces a “stop signal” that prematurely stops a complete and functional protein from being made

These specific mutation types are identified through genetic testing.

Percentage of mutation types in the United States

Mutation_piechart.png

Diagnosis

"I want my child to receive the correct diagnosis, but I don’t know enough about the testing process."

Diagnosing Duchenne can be a challenge. Often, there is a delay of about 2 to 3 years between the appearance of the first signs and symptoms and a confirmed diagnosis. On average, Duchenne is diagnosed by age 4.

The delay in diagnosis may be because:

  • Early signs and symptoms of the disease may not appear until a child is approximately 2 years old
  • There may be no family history of Duchenne
  • A parent may not tell their child’s doctor about early signs and symptoms because they may not recognize early delayed development
  • The disease is so rare, it is possible that many doctors have never seen a patient with Duchenne and may not be familiar with the signs and symptoms

It is important to report any symptoms to your child’s doctor as soon as possible to help minimize delays in diagnosis and ensure that your child is receiving the necessary testing.

Diagnosing Duchenne requires 3 steps:

Step 1—Observing signs and symptoms

Those observations can be made by:

  • A parent or other family member
  • A child’s pediatrician or family doctor
  • A school nurse or teacher
  • A physical therapist or other specialist who provides care to children with the specific challenges associated with Duchenne muscular dystrophy

Observations may include:

  • Difficulty running, jumping, climbing stairs compared with other children of similar age
  • Gowers maneuver
  • Speech delay, abnormal gait (way of walking), frequent falling, walking on tip-toes, enlarged calf muscles

Step 2—Blood tests to determine enzyme levels

If signs and symptoms of Duchenne are observed, a doctor may recommend blood tests. Blood tests show whether certain blood levels fall within a normal range. A doctor may check levels of the liver enzymes aspartate aminotransferase (AST) and alanine aminotransferase (ALT), high levels of which can result from muscular dystrophies. If liver enzyme levels are above the normal range of 10-40 units per liter (U/L) for AST and 7-56 U/L for ALT, the doctor may then test for high creatine kinase (CK) levels.

CK is an enzyme that is found in the heart, brain, skeletal muscle, and other tissues in the body. High levels of CK indicate muscle damage.

Range of CK levels

22-198 U/L Normal range
3,000-3,500 U/L Duchenne muscular dystrophy

If a child has a high CK level, he or she should be taken, as soon as possible, to a neuromuscular specialist to confirm or rule out a diagnosis of Duchenne with the use of genetic testing.

Step 3—Genetic testing

Genetic testing is used to confirm the majority of Duchenne diagnoses and can be done with a simple blood test. Full gene sequencing can help identify the specific type of mutation that is causing a child’s Duchenne muscular dystrophy, and that can affect how the condition is managed.

Other tests that have been used to diagnose Duchenne include muscle biopsies and electromyography (EMG). An EMG is a test that checks the health of the muscles or nerves that control them. Muscle biopsy and EMG are becoming less common as a means to diagnose Duchenne. A muscle biopsy cannot determine the exact mutation that is causing Duchenne.

Decode Duchenne provides free genetic testing and counseling to people who have been unable to access genetic testing because of financial barriers. Decode Duchenne is administered by DuchenneConnect, a program of Parent Project Muscular Dystrophy. To learn more, contact a DuchenneConnect Coordinator at coordinator@duchenneconnect.org or call (201) 937-1408 (Monday-Friday, 8 AM-5 PM EST).

Getting a confirmed diagnosis as soon as possible is important because:

  • The earlier treatment and management strategies are started, the better the chance of preserving muscle strength and function for a longer period of time
  • It encourages the urgency for genetic testing, the results of which
    • can help determine the specific mutation that caused Duchenne, providing the opportunity to manage the disease with a more targeted approach
    • can allow parents to make informed family-planning decisions

Disease management strategies that are dependent on a child’s specific mutation type are in development.

Manage Symptoms

"I want to know how to help manage my child’s symptoms."

Current disease management strategies focus on maintaining muscle function for as long as possible and managing the symptoms of Duchenne. Those strategies include:

Corticosteroids (steroid medications)

Corticosteroids are the most commonly used treatment for Duchenne. While they do not address the underlying cause of the disease, they can help manage the symptoms of the disease by preserving muscle strength and movement, and by minimizing later complications, such as scoliosis (a curvature of the spine) and trouble breathing.

It is important to monitor children who take steroids over a long period of time because the drugs can cause serious side effects. Speak with your doctor for more information about these side effects.

Other ways to treat or ease the symptoms of Duchenne

  • Leg braces and wheelchairs
  • Surgeries that may help with tightness in the joints and scoliosis
  • Devices that help with breathing
  • Medicines for the heart
  • Physical therapy
  • Regular, moderate exercise
  • Supplements, including vitamin D and calcium to help keep bones strong
  • A diet high in fluid and fiber may help ease constipation that can be caused by weak muscles

All over the world, scientists are researching new disease management strategies for Duchenne to help treat the disease. A doctor can help determine which disease management strategies are appropriate for a child with Duchenne.

Although caring for a child with Duchenne requires that many healthcare professionals work together, a child’s primary doctor, often a neurologist, will coordinate the care.

Various healthcare professionals will be needed at different stages of the disease. They provide support to maximize quality of life and help maintain independence. When all those involved in a child’s care work together, the challenges associated with Duchenne can be easier to manage.

The Duchenne care team

duchenne-daisy-wheel.png

Other healthcare professionals who may be needed to care for a child with Duchenne include a dietitian/nutritionist, gastroenterologist, and speech therapist. The neurologist will coordinate those specialists when necessary.

Click here for additional important care information for the different phases of Duchenne.

If you suspect your child has Duchenne, talk to your child’s doctor as soon as possible. The earlier your child receives a diagnosis, the sooner your family can create an empowering disease management strategy.

"I want to stay connected with the Duchenne community."