Word On Charcot-Marie-Tooth Disease (CMT)

Our grateful thanks to the charity CMTUK (www.cmt.org.uk) for their input to our radio feature, which you can hear again via the audio player at the bottom of this page.   

Charcot-Marie-Tooth disease (CMT) is a group of inherited neurological disorders that affect the peripheral nerves, which are responsible for sending signals between the central nervous system and the muscles and sensory organs.

CMT is one of the most common inherited neurological conditions, impacting roughly 1 in 2,500 people worldwide.

CMT is named after the three physicians who first described it in 1886: Jean-Martin Charcot, Pierre Marie, and Howard Henry Tooth.

CMT is a hereditary motor and sensory neuropathy, which means it affects both movement and sensation. The disease causes progressive muscle weakness and atrophy, primarily in the feet, legs, hands, and arms. It arises from genetic mutations that damage the nerves' protective myelin sheath or the nerve fibers (axons) themselves, leading to reduced transmission of nerve signals to muscles.

Who is at Risk of Developing CMT? CMT is an inherited disorder, so those at risk are individuals with a family history of the disease. The disease can be passed down through several types of inheritance patterns:

• Autosomal Dominant: In this case, only one copy of the mutated gene from either parent is needed to cause CMT.
• Autosomal Recessive: Here, a person would need to inherit two copies of the mutated gene, one from each parent, to develop the disease.
• X-Linked: The mutation is on the X chromosome, so it’s more commonly expressed in males but can also affect females.

If a person has a parent with CMT, they are at risk of inheriting it. However, spontaneous genetic mutations can also cause the disease in people without a family history.

Symptoms of CMT typically begin in adolescence or early adulthood, but the age of onset and severity can vary widely. Common symptoms include:

• Muscle Weakness: Often starts in the lower legs and feet, leading to difficulty walking, frequent tripping, and trouble lifting the feet (foot drop).
• Foot Deformities: High arches, flat feet, and hammertoes are common as the foot muscles weaken and lose support.
• Reduced Sensation: People with CMT often experience a loss of sensation in the feet, lower legs, hands, and arms.
• Muscle Atrophy: As the disease progresses, muscle wasting becomes more pronounced, leading to thinner, less functional extremities.
• Balance Issues: Due to weakened muscles and reduced sensation, individuals may experience balance problems and difficulty coordinating movements.
• Hand Weakness: As the disease progresses, it can also affect the hands, making it difficult to grip objects or perform fine motor tasks.
• Pain: Some people experience nerve pain, often described as burning or aching.

Treatments for Charcot-Marie-Tooth Disease.  Currently, there is no cure for CMT, but several treatments can help manage symptoms, slow disease progression, and improve quality of life:

• Physical Therapy: Regular stretching, strengthening exercises, and low-impact aerobic activities can help maintain muscle strength, flexibility, and endurance.
• Occupational Therapy: Therapy can assist individuals in adapting daily activities to cope with muscle weakness and prevent injuries.
• Orthopedic Devices: Braces, splints, and other supportive devices can improve mobility, reduce strain on weakened muscles, and help correct foot deformities.
• Pain Management: Pain medications or other treatments may be recommended to manage discomfort from nerve pain.
• Orthopedic Surgery: In some cases, surgery may be considered to correct severe foot deformities or other complications.
• Genetic Counseling: For families with a history of CMT, genetic counseling can help assess risks for future generations.

Research into gene therapies, drug treatments, and other therapies continues, with the hope of developing more targeted treatments

Listen to this weeks radio report