Charcot-Marie-Tooth disease

Charcot-Marie-Tooth disease

Overview

Charcot (shahr-KOH)-Marie-Tooth disease is a group of inherited disorders that cause nerve damage. This damage is mostly in the arms and legs (peripheral nerves). Charcot-Marie-Tooth disease is also called hereditary motor and sensory neuropathy.

Charcot-Marie-Tooth disease results in smaller, weaker muscles. You may also experience loss of sensation and muscle contractions, and difficulty walking. Foot deformities such as hammertoes and high arches also are common. Symptoms usually begin in the feet and legs, but they may eventually affect your hands and arms.

Symptoms of Charcot-Marie-Tooth disease typically appear in adolescence or early adulthood, but may also develop in midlife.

Symptoms

Signs and symptoms of Charcot-Marie-Tooth disease may include:

Weakness in your legs, ankles and feet

Loss of muscle bulk in your legs and feet

High foot arches

Curled toes (hammertoes)

Decreased ability to run

Difficulty lifting your foot at the ankle (footdrop)

Awkward or higher than normal step (gait)

Frequent tripping or falling

Decreased sensation or a loss of feeling in your legs and feet

As Charcot-Marie-Tooth disease progresses, symptoms may spread from the feet and legs to the hands and arms. The severity of symptoms can vary greatly from person to person, even among family members.

Causes

Charcot-Marie-Tooth disease is an inherited, genetic condition. It occurs when there are mutations in the genes that affect the nerves in your feet, legs, hands and arms.

Sometimes, these mutations damage the nerves. Other mutations damage the protective coating that surrounds the nerve (myelin sheath). Both cause weaker messages to travel between your limbs and brain.

Risk factors

Charcot-Marie-Tooth disease is hereditary, so you're at higher risk of developing the disorder if anyone in your immediate family has the disease.

Other causes of neuropathies, such as diabetes, may cause symptoms similar to Charcot-Marie-Tooth disease. These other conditions can also cause the symptoms of Charcot-Marie-Tooth disease to become worse. Medications such as the chemotherapy drugs vincristine (Marqibo), paclitaxel (Abraxane) and others can make symptoms worse. Be sure to let your doctor know about all of the medications you're taking.

Complications

Complications of Charcot-Marie-Tooth disease vary in severity from person to person. Foot abnormalities and difficulty walking are usually the most serious problems. Muscles may get weaker, and you may injure areas of the body that experience decreased sensation.

Sometimes the muscles in your feet may not receive your brain's signal to contract, so you're more likely to trip and fall. And your brain may not receive pain messages from your feet, so if you've rubbed a blister on your toe, for example, it may get infected without your realizing it.

You may also experience difficulty breathing, swallowing or speaking if the muscles that control these functions are affected by Charcot-Marie-Tooth disease.

Diagnosis

During the physical exam, your doctor may check for:

Signs of muscle weakness in your arms, legs, hands and feet

Decreased muscle bulk in your lower legs, resulting in an inverted champagne bottle appearance

Reduced reflexes

Sensory loss in your feet and hands

Foot deformities, such as high arches or hammertoes

Other orthopedic problems, such as mild scoliosis or hip dysplasia

Your doctor may also recommend the following tests, which can help provide information about the extent of your nerve damage and what may be causing it.

Nerve conduction studies. These tests measure the strength and speed of electrical signals transmitted through your nerves. Electrodes on the skin deliver small electric shocks to stimulate the nerve. Delayed or weak responses may indicate a nerve disorder such as Charcot-Marie-Tooth disease.

Electromyography (EMG). A thin needle electrode is inserted through your skin into the muscle. Electrical activity is measured as you relax and as you gently tighten the muscle. Your doctor may be able to determine the distribution of the disease by testing different muscles.

Nerve biopsy. A small piece of peripheral nerve is taken from your calf through an incision in your skin. Laboratory analysis of the nerve distinguishes Charcot-Marie-Tooth disease from other nerve disorders.

Genetic testing. These tests, which can detect the most common genetic defects known to cause Charcot-Marie-Tooth disease, are done with a blood sample. Genetic testing may give people with the disorder more information for family planning. It can also rule out other neuropathies. Recent advances in genetic testing have made it more affordable and comprehensive. Your doctor may refer you to a genetic counselor before testing so you can best understand the pros and cons of testing.

Treatment

There's no cure for Charcot-Marie-Tooth disease. But the disease generally progresses slowly, and it doesn't affect expected life span.

There are some treatments to help you manage Charcot-Marie-Tooth disease.

Medications

Charcot-Marie-Tooth disease may sometimes cause pain due to muscle cramps or nerve damage. If pain is an issue for you, prescription pain medication may help control your pain.

Therapy

Physical therapy. Physical therapy can help strengthen and stretch your muscles to prevent muscle tightening and loss. A program usually includes low-impact exercises and stretching techniques guided by a trained physical therapist and approved by your doctor. Started early and followed regularly, physical therapy can help prevent disability.

Occupational therapy. Weakness in the arms and hands can cause difficulty with gripping and finger movements, such as fastening buttons or writing. Occupational therapy can help through the use of assistive devices, such as special rubber grips on doorknobs, or clothing with snaps instead of buttons.

Orthopedic devices. Many people with Charcot-Marie-Tooth disease require the help of certain orthopedic devices to maintain everyday mobility and to prevent injury. Leg and ankle braces or splints can provide stability while walking and climbing stairs.

Consider boots or high-top shoes for additional ankle support. Custom-made shoes or shoe inserts may improve your gait. Consider thumb splints if you have hand weakness and difficulty with gripping and holding things.

Surgery

If foot deformities are severe, corrective foot surgery may help alleviate pain and improve your ability to walk. Surgery can't improve weakness or loss of sensation.

Potential future treatments

Researchers are investigating a number of potential therapies that may one day treat Charcot-Marie-Tooth disease. Potential therapies include medications, gene therapy and in vitro procedures that may help prevent passing the disease to future generations.

Type of Doctor Department : A neurologist