Hereditary muscular dystrophy is one of the genetic diseases that greatly affect the patient's life, as it causes the patient's muscles to weaken gradually, which leads to muscle deterioration, in this article, we will review the causes and factors that lead to the development of this disease, in addition to the symptoms, diagnostic methods and treatments available at Almoosa Specialty Hospital.

What is hereditary muscular dystrophy?

Hereditary muscular dystrophy is a group of genetic diseases that affect the muscles and lead to their weakness and deterioration over time, and this occurs as a result of genetic mutations that affect the genes that control the formation of proteins important for building and maintaining muscles, and this leads to a gradual deterioration in the ability to move and perform daily activities. 

What are the types of hereditary muscular dystrophy?

There are several types of hereditary muscular dystrophy:

• Duchenne: This type usually begins in childhood, causing weakness in the muscles of the legs and pelvis first and then progresses to include the rest of the body's muscles. It develops rapidly and is the most common type in male children due to its association with the X chromosome.
• Becker: Similar to Duchenne but develops more slowly and usually begins in adolescence or young adulthood.
• Spinal muscular atrophy: This type affects the motor neurons in the spinal cord that control the muscles, which leads to muscle weakness, can appear at different stages of life, from childhood to adulthood, and there are several subtypes. 
• Proliferative muscular dystrophy: The proliferative type affects the muscles of the upper and lower extremities, where muscle weakness begins in the pelvis and shoulders, can appear at any age, and varies in severity from person to person.
• Polar muscular dystrophy: It usually starts in the facial muscles, then moves to the shoulders and arms, and is characterized by progressive muscle weakness and tends to progress slowly. 
• Diversified muscular dystrophy: Initially affecting the muscles of the eyes and pharynx, it may cause difficulty in swallowing and eye movement, usually appearing in late adulthood or after the age of 40.
• Tendinosis: Seen in early childhood through adulthood but common in adults, symptoms are prolonged muscle spasm and stiffness after use.

Causes of Hereditary Muscular Dystrophy

Each type of muscular dystrophy is caused by a different set of mutations, but they all prevent the body from producing dystrophin, a protein essential for building, repairing, and maintaining muscles, and the causes in each type include the following:

• Mutations in one or more of the genes that carry instructions for making the proteins that muscles need to grow and function normally, causing them to weaken and atrophy over time.
• Patterns of inheritance, which can pass these genetic mutations from parents to children in different genetic patterns, either recessive inheritance, where a person inherits two mutated copies of the gene, one from each parent, to develop the disease, or dominant inheritance, where a person inherits one mutated copy of the gene from one parent to develop the disease.
• Sex-linked inheritance, where the mutated gene is located on the X chromosome, so males will have the disease if they have one mutated copy, while females have two X chromosomes, so they may be carriers without symptoms or may have less severe symptoms if they have two mutated copies. 
• De novo mutations, when a gene mutation occurs for the first time in an affected person and is not inherited from parents, but can be passed on to future generations.

How to diagnose hereditary muscular dystrophy

The diagnosis of muscular dystrophy is based on مركز العلوم العصبية At Al Mousa Specialist Hospital A set of medical tests that help determine the type and progression of the disease, and the diagnostic methods include the following:  

• Clinical examination and family history, the doctor assesses symptoms such as muscle weakness, difficulty moving, spasms, loss of balance, and whether there is a family history of the disease.
• Genetic tests, such as DNA analysis to detect the genetic mutations that cause the disease, help confirm the diagnosis and determine the exact genotype.
• CPK muscle enzyme test, where levels are elevated when muscles are damaged.
• Electromyography (EMG), a test of electrical activity in muscles to detect any impairment in nerve signaling.
• Muscle biopsy, taking a small sample of muscle tissue and analyzing it under a microscope to detect changes in the structure of muscle fibers.
• Magnetic resonance imaging (MRI) helps determine the extent of muscle damage and monitor the progression of the disease.  

How to treat hereditary muscular dystrophy

There are several treatment options that can help manage symptoms and improve the quality of life of a hereditary muscular dystrophy patient, such as Occupational therapy As there is no definitive cure for the disease, treatments available at Almoosa Specialty Hospital include the following:

• Physical therapy: To maintain muscle strength and flexibility, and improve mobility. 
• Occupational therapy: To help learn how to perform daily tasks independently, such as dressing, bathing and eating.
• Treatment with medications: To help manage symptoms, such as steroids to reduce inflammation, or medications to help improve muscle function.
• Use assistive devices: Such as walkers and wheelchairs, to help with mobility.
• Treatment with surgery: Surgery may be necessary in some cases to correct bone or joint abnormalities.

There is ongoing research into gene therapy and stem cell therapy for hereditary muscular dystrophy, and these treatments may be available in the future.

What are the complications of hereditary muscular dystrophy? 

Hereditary muscular dystrophy leads to a variety of complications, which vary depending on the type of muscular dystrophy as well as its severity:

• Problems with mobility and difficulty walking, running or jumping.
• Frequent falls.
• Loss of use of the arms and hands.
• The need to use a wheelchair.
• Breathing issues due to weakened breathing muscles, resulting in difficulty breathing.
• The need to use a ventilator.
• Heart issues due to cardiomyopathy, which affects the heart's ability to pump blood, and irregular heartbeats.
• Difficulty swallowing, leading to malnutrition or choking.
• Joint deformities and stiffness. 
• Growth retardation.
• صعوبات التعلم. 

Frequently asked questions

At what age does a person with muscular dystrophy die?

There is no specific age of death for patients with hereditary muscular dystrophy, as life expectancy varies greatly based on several factors, including:

•  Type of muscular dystrophy: Each type of hereditary muscular dystrophy has different developmental pathways. Duchenne muscular dystrophy is usually more severe and leads to death at a young age, while other types may allow for a longer lifespan.
• Severity of the disease: Even within a single type of muscular dystrophy, the severity of symptoms can vary from person to person.
• Quality of medical care: Getting quality medical care, including physical, respiratory and cardiac care, can help improve quality of life and prolong a patient's lifespan.
• Complications: Reaching complications such as breathing or heart issues affect life expectancy significantly.

Is muscular dystrophy inherited?

Yes, hereditary muscular dystrophy can be passed on to children, but the method of transmission depends on the type of disease and the pattern of genetic inheritance:  

• X-linked genetics, such as Duchenne and Becker dystrophies.
• Recessive inheritance, such as spinal muscular atrophy and some other types.
• Autosomal dominant genetics, such as some types of spinal muscular atrophy.
• New random mutations.  

Transmission of the disease can be avoided through pre-marital or pre-pregnancy genetic testing to determine the likelihood of transmitting the disease, and in some cases, genetic techniques such as preimplantation genetic diagnosis can be used to select unaffected embryos when resorting to artificial insemination.  

Do muscles return to normal after atrophy?

Unfortunately, in most cases of hereditary muscular dystrophy, the muscles cannot return to normal because the disease is caused by a genetic defect that affects the production of proteins necessary for healthy muscles.

In conclusion, although there is no definitive cure for most types of hereditary muscular dystrophy, medical advances in early diagnosis as well as drug therapies, physical therapy, and gene therapy are helping to slow the progression of the disease and improve patients' quality of life.  

Almoosa Specialty Hospital provides integrated services for the treatment of hereditary muscular dystrophy through its specialized centers, the Neuroscience Center, Almoosa Rehabilitation Hospital, and the Pediatric Rehabilitation Center. 

To take advantage of these services, it is advisable to contact Almoosa Specialist Hospital directly to schedule appointments and get more information about available treatment programs. 

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