Summary about Disease
Facioscapulohumeral muscular dystrophy (FSHD) is a genetic muscle disorder characterized by progressive muscle weakness, primarily affecting the face (facio-), shoulders (scapulo-), and upper arms (humeral). The weakness typically begins in these areas, but can spread to other muscles in the body, including the abdomen, legs, and feet. The severity and progression of FSHD vary significantly from person to person, even within the same family.
Symptoms
Facial weakness: Difficulty smiling, whistling, closing eyes tightly.
Shoulder weakness: Difficulty raising arms above head, winging of the scapula (shoulder blade).
Upper arm weakness: Difficulty with activities like lifting objects or brushing hair.
Abdominal weakness: Protruding abdomen, difficulty with core stability.
Foot drop: Difficulty lifting the front of the foot, leading to tripping.
Hearing loss: Can occur in some individuals.
Retinal vascular abnormalities: Typically asymptomatic but detectable on eye examination.
Muscle pain: Some individuals experience muscle pain or fatigue.
Causes
FSHD is primarily caused by genetic mutations affecting the DUX4 gene region on chromosome 4. There are two main types:
FSHD1: This is the more common type (95% of cases) and is caused by a contraction (shortening) of a repeated DNA sequence (D4Z4) in the DUX4 gene region. This contraction leads to abnormal expression of the *DUX4* gene, resulting in the production of a toxic protein that damages muscle cells.
FSHD2: This less common type is caused by mutations in genes that affect the regulation of the DUX4 gene. These mutations lead to the same outcome as FSHD1: abnormal *DUX4* expression.
Medicine Used
Currently, there is no cure for FSHD, and no medications specifically target the underlying genetic cause. Treatment focuses on managing symptoms and improving quality of life.
Physical Therapy: Helps maintain muscle strength and flexibility.
Occupational Therapy: Provides adaptive strategies and assistive devices to help with daily activities.
Pain Management: Medications like NSAIDs or other analgesics may be used to manage muscle pain.
Surgical Interventions: In some cases, surgery may be recommended to stabilize the scapula or correct foot drop.
Albuterol: Some studies have suggested that albuterol, a medication typically used for asthma, may have a modest effect on muscle strength in some individuals with FSHD. However, more research is needed.
Is Communicable
No, FSHD is not communicable. It is a genetic disorder caused by gene mutations and is not infectious.
Precautions
There are no specific precautions to prevent FSHD, as it is a genetic condition. However, for individuals diagnosed with FSHD, the following precautions are important:
Regular Medical Care: Follow-up with a neurologist and other healthcare professionals is crucial for monitoring disease progression and managing symptoms.
Physical Therapy: Adherence to a physical therapy program can help maintain muscle strength and flexibility.
Fall Prevention: Take measures to prevent falls, such as using assistive devices and modifying the home environment.
Avoid Overexertion: Avoid activities that cause excessive fatigue or muscle strain.
Genetic Counseling: If planning to have children, genetic counseling is recommended to discuss the risk of passing on the gene.
How long does an outbreak last?
FSHD is not an "outbreak" situation. It is a chronic, progressive genetic condition. Symptoms develop over a lifetime and do not suddenly appear and disappear like an infectious disease. The progression of the disease can vary greatly from person to person.
How is it diagnosed?
Clinical Examination: A neurologist will perform a thorough physical examination to assess muscle weakness patterns.
Family History: A detailed family history of muscle weakness is important.
Genetic Testing: A blood test is used to analyze the DUX4 gene region on chromosome 4. For FSHD1, the size of the D4Z4 repeat is measured. For FSHD2, other genes are analyzed for mutations.
Electromyography (EMG): This test measures the electrical activity of muscles and can help identify muscle damage.
Muscle Biopsy: In some cases, a muscle biopsy may be performed to examine muscle tissue under a microscope.
Timeline of Symptoms
The age of onset and the timeline of symptom progression vary considerably in FSHD.
Childhood or Adolescence: Some individuals may experience the first signs of muscle weakness in childhood or adolescence, often with difficulty raising their arms or facial weakness.
Adulthood: Others may not notice symptoms until adulthood.
Progression: The rate of progression is also variable. Some individuals experience a slow, gradual decline in muscle strength over many years, while others experience more rapid progression. Symptoms tend to spread from the face, shoulders, and upper arms to other muscles in the body over time.
Important Considerations
Variability: The severity and progression of FSHD vary significantly, making it difficult to predict the course of the disease in any individual.
Genetic Counseling: Genetic counseling is essential for families affected by FSHD, to understand the inheritance pattern and risks to future generations.
Multidisciplinary Care: Management of FSHD requires a multidisciplinary approach, involving neurologists, physical therapists, occupational therapists, and other healthcare professionals.
Research: Research into new treatments for FSHD is ongoing. Clinical trials are available for some individuals.
Support Groups: Connecting with other individuals and families affected by FSHD can provide emotional support and practical advice.