Question: What is (are) Duchenne muscular dystrophy ?
Answer: Duchenne muscular dystrophy (DMD) is a rapidly progressive form of muscular dystrophy that occurs primarily in boys. It is caused by a mutation in a gene, called the DMD gene, which encodes the muscle protein dystrophin. Boys with Duchenne muscular dystrophy do not make the dystrophin protein in their muscles. Duchenne mucular dystrophy is inherited in an X-linked recessive fashion; however, it may also occur in people from families without a known family history of the condition. Individuals who have DMD have progressive loss of muscle function and weakness, which begins in the lower limbs. In addition to the skeletal muscles used for movement, DMD may also affect the muscles of the heart. There is no known cure for Duchenne muscular dystrophy. Treatment is aimed at control of symptoms to maximize the quality of life.
Source: GARD

Question: What are the symptoms of Duchenne muscular dystrophy ?
Answer: What are the signs and symptoms of Duchenne muscular dystrophy? The Human Phenotype Ontology provides the following list of signs and symptoms for Duchenne muscular dystrophy. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Arrhythmia - Calf muscle pseudohypertrophy - Childhood onset - Congestive heart failure - Dilated cardiomyopathy - Elevated serum creatine phosphokinase - Flexion contracture - Gowers sign - Hyperlordosis - Hyporeflexia - Hypoventilation - Intellectual disability, mild - Muscular dystrophy - Muscular hypotonia - Respiratory failure - Scoliosis - Waddling gait - X-linked recessive inheritance - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.
Source: GARD

Question: Is Duchenne muscular dystrophy inherited ?
Answer: How do people inherit Duchenne and Becker muscular dystrophy? Duchenne and Becker muscular dystrophy are inherited in an X-linked recessive pattern. A condition is considered X-linked if the mutated gene that causes the disorder is located on the X chromosome, one of the two sex chromosomes. In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition. In females (who have two X chromosomes), a mutation must be present in both copies of the gene to cause the disorder. Males are affected by X-linked recessive disorders much more frequently than females. A striking characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons. In about two thirds of cases, an affected male inherits the mutation from a mother who carries an altered copy of the DMD gene. The other one third of cases probably result from new mutations in the gene. In X-linked recessive inheritance, a female with one mutated copy of the gene in each cell is called a carrier. She can pass on the altered gene, but usually does not experience signs and symptoms of the disorder. Occasionally, however, females who carry a DMD mutation may have muscle weakness and cramping. These symptoms are typically milder than the severe muscle weakness and atrophy seen in affected males. Females who carry a DMD mutation also have an increased risk of developing heart abnormalities including dilated cardiomyopathy.
Source: GARD

Question: How to diagnose Duchenne muscular dystrophy ?
Answer: How is Duchenne muscular dystrophy (DMD) diagnosed? Duchenne muscular dystrophy (DMD) is suspected and diagnosed when the following clinical findings are found: a positive family history of DMD, more men affected that women in a family, progressive muscle weakness which is usually greater in the proximal muscles (closest to the trunk of the body) than distal muscles (those farthest away from the hips and shoulders such as those in the hands, feet, lower arms or lower legs), symptoms before the age of 5 years old and wheel chair dependency before age 13. Testing for DMD includes: a blood test which measures the levels of serum creatine phosphokinase (CPK); electromyography which is used to distinguish conditions that only impact the muscles (myotonic) from those that involve that brain and muscles (neurogenic); a skeletal muscle biopsy which is used to detect the presence of specific proteins with a visible label (immunohistochemistry) and molecular genetic testing for deletions, duplications, rearrangements, etc. of genetic material.
Source: GARD

Question: What are the treatments for Duchenne muscular dystrophy ?
Answer: How might Duchenne muscular dystrophy be treated? There is no known cure for Duchenne muscular dystrophy (DMD). Treatment is aimed at the control of symptoms to maximize the quality of life. Individuals with DMD often experience dilated cardiomyopathy (the heart becomes larger and weaker). This can be treated with medications and in severe cases a heart transplant may be necessary. Assistive devices for breathing difficulties may be needed, especially at night. Physical activity is encouraged for individuals with Duchenne muscular dystrophy. Physical inactivity (such as bed rest) can worsen the muscle disease. Physical therapy may be helpful to maintain muscle strength and function. Orthopedic devices (such as braces and wheelchairs) may improve the ability to move and take care of oneself. Steroids are usually given to individuals with Duchenne muscular dystrophy to help improve the strength and function of muscles. There are a few different steroids that can be used to treat DMD: Prednisone is a steroid that has been shown to extend the ability to walk by 2 to 5 years. However, the possible side effects of prednisone include weight gain, high blood pressure, behavior changes, and delayed growth. Deflazacort (another form of prednisone), is used in Europe and believed to have fewer side effects. Oxandrolone, a medication used in a research study, also has similar benefits to prednisone, but with fewer side effects. Cyclosporine has also been used as a treatment for DMD, and has improved muscle function in children. Although, its use is controversial because it can cause myopathy, which is a muscle disease that causes muscle weakness. There are several other therapies that are also being researched, including exon skipping drugs, coenzyme Q10, idebenone, glutamine, and pentoxifylline.
Source: GARD