DMD Disease (Duchenne Muscular Dystrophy) Symptoms, Causes, and Treatment Methods

DMD Disease

DMD disease is a genetic muscle disorder seen in childhood that leads to progressive muscle weakness. This disease usually appears in boys and significantly reduces the quality of life by affecting basic skills such as walking and moving over time. With early diagnosis, a multidisciplinary treatment approach, and family support, the progression of the disease can be slowed.

What is DMD Disease?

DMD disease is an abbreviation for Duchenne Muscular Dystrophy and is a hereditary condition, also known as dmd muscle wasting disease, that causes progressive weakening of muscle tissue. This dmd muscle disease is classified as an X-linked recessive genetic disorder, particularly seen in boys. The name of the disease comes from the French neurologist Guillaume Duchenne, who first described this condition in detail in the 1860s.

DMD is the most common and severe form among types of muscular dystrophy. The disease occurs as a result of the deficiency or absence of the dystrophin protein, which protects the structure and function of muscle fibers. Dystrophin protein is a critical building block that strengthens the membrane of muscle cells and prevents the muscle from being damaged during contraction. Although this genetic disorder is present in the body from birth, it usually begins to show symptoms in early childhood. Since the disease is progressive, muscle weakness increases and mobility decreases over time. DMD can affect not only skeletal muscles but also the heart muscle, leading to cardiomyopathy. A case of DMD is seen in every 3,500-5,000 male births worldwide. This statistic reveals how common the disease is and its importance in terms of public health.

What Are the Symptoms of DMD Disease?

Symptoms of DMD disease usually begin to be noticed between the ages of 2-5. In the early period, families may observe that their children experience delays in motor development compared to their peers. A delay in the age of starting to walk is one of the earliest signs of this disease.

Muscle Weakness: Among the symptoms of dmd muscle disease, muscle weakness is the most characteristic and usually starts from the hips, thigh muscles, and shoulder girdle muscles. Children have to support their legs with their hands when getting up from the floor; this situation is called the "Gowers' maneuver." Difficulty climbing stairs, decreased ability to run, and a tendency to fall frequently are also common among the symptoms of DMD disease.

Gait Disorders: Within the symptoms of dmd muscle disease, changes in the child's walking style emerge as the disease progresses. A walking style called waddling gait, which involves swaying the hips, develops. A tendency to walk on tiptoes is also frequently observed. Paradoxically, despite a decrease in muscle mass, an enlargement (pseudohypertrophy) can be observed, especially in the calf muscles.

Respiratory and Heart Problems: DMD is not limited to physical muscle weakness. In the later stages of the disease, respiratory muscles are also affected, which leads to difficulty breathing and respiratory problems. As a result of the heart muscle being affected, cardiomyopathy may develop, and this situation can become life-threatening.

Mental Problems: In terms of cognitive development, mild learning difficulties can be seen in approximately one-third of children with DMD. However, this situation is not directly related to the underlying muscle problems of the disease, and the intelligence levels of the children are generally within normal limits.

What Causes DMD Disease?

The causes of DMD disease are mutations in the DMD gene located on the X chromosome. The dystrophin gene produces a protein called "dystrophin" that provides durability to muscle cells. However, due to an error in this gene, sufficient or functional dystrophin cannot be produced. As a result, muscle cell membranes weaken, and muscle cells are easily damaged and die. DMD shows X-linked recessive inheritance. Since boys have a single X chromosome, if there is a mutation on this chromosome, the disease occurs. In girls, since there are two X chromosomes, the healthy chromosome usually compensates for the disease, and girls remain in a state of "DMD disease carrier status."

However, in some rare cases, mild muscle weakness or heart problems can also be seen in carrier women. New mutations are also possible. That is, even if there is no genetic history in the family, DMD can develop in a child for the first time. In approximately one-third of children with DMD, the disease occurs with a random genetic mutation without familial transmission.

How Is DMD Disease Diagnosed?

Diagnosis of DMD disease is of critical importance for the management and treatment planning of the disease. The first step is to take a detailed medical history and perform a physical examination. The doctor inquires about the child's motor development history, symptoms of muscle weakness, and family history. In the physical examination, specific tests such as muscle strength tests, gait analysis, and Gowers' maneuver are performed.

In blood tests, the creatine kinase (CK) enzyme level is a critical marker. In patients with DMD, the CK level can be 10-100 times higher than normal. This elevation is accepted as an indicator of muscle damage and plays an important role in the early diagnosis of the disease. Genetic tests are necessary for a definitive diagnosis. Mutations in the DMD gene are detected by DNA analysis. Modern methods such as Multiplex PCR, CGH array, and next-generation sequencing techniques can detect more than 99% of mutations.

In some cases, a muscle biopsy may be required. This invasive test is performed by examining a small sample taken from muscle tissue under a microscope. The biopsy directly shows the presence of the dystrophin protein and confirms the diagnosis. Electromyography (EMG) and nerve conduction studies can be used to evaluate muscle and nerve functions. These tests help to show that the muscle disease does not originate from the nervous system.

How Is DMD Disease Treated?

There is no definitive cure for DMD disease yet. However, various treatment methods are used to slow the progression of the disease, prevent complications, and improve the patient's quality of life. The treatment process for dmd muscle disease is carried out with a multidisciplinary approach and includes the following elements:

Corticosteroid Medications: Steroid medications such as prednisone and deflazacort can temporarily increase muscle strength and help muscles remain functional for longer. However, side effects such as weight gain, osteoporosis, and high blood pressure can be seen with long-term use.

Physiotherapy and Rehabilitation: DMD disease can be supported with physical therapy. Regular exercise and physical therapy should be performed to maintain muscle flexibility and prevent muscle stiffness. These therapies are also very important to prevent the development of scoliosis.

Orthotics and Walking Aids: During the period when leg muscles weaken, walking duration can be extended by using walking apparatus. In later stages, wheelchair support is required.

Respiratory Support: In the later stages of the disease, respiratory muscles weaken. Therefore, respiratory functions should be monitored, and nocturnal devices or ventilators (CPAP, BiPAP) should be used when necessary.

Heart Monitoring and Treatment: Since DMD can also affect heart muscles, regular cardiological control is required. If heart rhythm disorders or heart failure develop, medication is applied.

Gene Therapies and New Treatment Methods: Next-generation treatment approaches are promising. Innovative methods such as stem cell therapy for DMD disease, gene therapy, and exon skipping techniques are being tested in clinical trials. These treatments aim to target the genetic basis of the disease.

Frequently Asked Questions

DMD (Duchenne Muscular Dystrophy) is a genetic disease. It occurs as a result of mutations in the dystrophin gene located on the X chromosome. It is usually passed from mother to son. While women can be carriers, the disease is mostly seen in boys. However, rarely, the disease can occur with a new mutation, meaning it can develop without a previous history of DMD in the family. DMD disease usually shows its first symptoms between the ages of 2 and 6. Delays in walking, frequent falling, difficulty climbing stairs, and backwardness in running ability are observed in children. In some cases, symptoms can be noticed at earlier ages. DMD is a progressive disease. Over time, muscle cells weaken, lose their function, and are replaced by connective tissue. First, the leg muscles are affected, then it spreads to the arm, shoulder, back, respiratory, and heart muscles. When adolescence is reached, most children have to use a wheelchair. The speed of the disease's progression can vary from person to person. For now, there is no definitive cure for DMD disease. However, the progression of the disease can be slowed with methods such as medications used, physiotherapy, and respiratory and heart support. In addition, studies on gene therapies are promising and have begun to be applied in some special cases. DMD is a chronic and lifelong disease. The disease continues to progress throughout life. However, with early diagnosis, regular care, and treatment, life expectancy can be extended, and quality of life can be improved. Especially with the development of supportive treatments in recent years, individuals with DMD can live a longer and higher-quality life. Due to the deficiency of the dystrophin protein, muscle cells are damaged more easily than normal. This situation causes the muscles to gradually weaken, muscle fibers to deteriorate, and be replaced by connective tissue. First, the leg and hip muscles are affected, then the upper body, respiratory, and heart muscles are also involved. In the diagnostic process, the creatine kinase (CK) level is first checked with blood tests. Then, mutations in the dystrophin gene are investigated with genetic tests. If necessary, advanced examinations such as muscle biopsy, electromyography (EMG), and MRI imaging can also be performed. Cardiological and respiratory tests are also applied regularly during the follow-up process. In the early stages of the disease, children can walk. However, as muscle weakness progresses, the ability to walk decreases over time. Usually, when they reach the age of 10-12, wheelchair use becomes inevitable. However, dmd disease can be slowed down with physiotherapy and orthopedic supports. The specialty that should be consulted for DMD diagnosis and follow-up is pediatric neurology. In addition, experts from different branches such as geneticists, orthopedics, physical therapy, chest diseases, and cardiology are also involved in the follow-up process. Therefore, a multidisciplinary approach is required. The care process is shaped according to the stage of the disease and generally requires continuous support. Regular physiotherapy, nutritional follow-up, respiratory and heart checks, psychological support, and social adaptation services form the basis of care. The education of family members and the strengthening of social support systems are also important in the care process.

If you have suspicions about DMD disease, it is of great importance to consult a pediatric neurology specialist without delay for early diagnosis and correct treatment. The expert team at Hisar Hospital is by your side in the diagnosis and treatment of DMD and other muscle diseases. Contact us immediately to get more information or to make an appointment.