5 Things to Know About Charcot-Marie-Tooth Disease
Despite the “tooth” in its name, Charcot-Marie-Tooth disease (CMT) has nothing to do with your teeth or mouth. The disease, which was named after the first three physicians to describe it — Jean-Martin Charcot, Pierre Marie and Howard Henry Tooth, is actually a neurological condition.
CMT affects your peripheral nerves, the nerves outside of your brain and spinal cord that send messages to the muscles and cells in your arms and legs. There are five types of CMT — CMT1, CMT2, CMT3, CMT4 and CMTX — with additional subtypes under CMT1, CMT2 and CMT4.
CMT, like many conditions, appears on a spectrum — some people are more affected than others. While I have many of the “markers” of CMT, I wasn’t officially diagnosed until I saw a geneticist for a separate condition. After reviewing my family’s medical history, and knowing my brother’s recent diagnosis, the doctor ran a blood test which confirmed my diagnosis.
Though symptoms of CMT can affect everyday life, it’s not considered a terminal illness, and those diagnosed with the condition have a normal life expectancy.
Here are five things you should know about Charcot-Marie-Tooth disease.
1. Most people who have CMT inherit it from a parent.
If you have CMT, there’s a good chance at least one of your parents has the condition as well. In many cases, the gene is either inherited in an autosomal dominant or autosomal recessive fashion, simply put either you get the mutated gene from one parent or both. You can also inherit the gene on your X chromosome, which determines which sex you are born — XX, female or XY, male.
In rare cases, CMT is the result of a de novo mutation, meaning the gene mutation just happens randomly without any family history.
The condition affects people of all genders equally.
2. Symptoms typically appear during adolescence.
CMT causes symptoms such as muscle weakness, loss of muscle mass and a loss of normal functioning in your limbs. These symptoms usually start during adolescence, though they can start earlier — as is the case for CMT3 — or later in life.
Other symptoms of CMT include:
- Loss of fine motor skills
- Stiffened joints
- Thickened nerves
- Decreased sensitivity to heat, touch and pain
- Frequent tripping or falling
- Drop foot
- Hammer toe
- High foot arch
- Flat feet
Symptoms typically develop slowly and gradually. Some people may require the use of mobility aids while others’ symptoms may not interfere with their daily functioning.
3. There are several tests that can help you get a diagnosis.
If your doctor suspects you have CMT, there are several tests they can run to confirm the diagnosis. First, your doctor will perform a physical exam to check for any of the symptoms listed above. They’ll also take a family history and ask if any family members have similar symptoms since most cases of CMT are inherited.
Next, your physician may order electrodiagnostic tests such as nerve conduction studies and electromyography (EMG). These tests can help doctors detect abnormalities in your peripheral nerves, the nerves affected by CMT.
Your doctor will also likely order blood tests to perform genetic testing. Not all CMT types can be diagnosed through blood tests, however.
If your doctor is still unsure of your diagnosis, they may do a nerve biopsy.
4. There is no cure for CMT but treatments might help.
Currently, there is no cure for Charcot-Marie-Tooth disease though research and gene therapy experiments are looking for ways to slow or stop disease progression.
While there might not be a cure, there are ways to manage symptoms. Physical and occupational therapy can help treat mobility- and motor-related symptoms. Mobility aids like canes, wheelchairs, braces and other orthopedic devices can also provide support. In some cases, surgery may help as well.
5. Though it’s a rare condition, there are plenty of ways to connect with others who have CMT.
It’s estimated CMT affects 19 per 100,000 people. Even though CMT is a rare condition, it’s important to know you’re not alone if you have it. There are plenty of organizations, from the Charcot-Marie-Tooth Association to Cure CMT4J, doing important work within the community.
If you’re looking to connect with others who live with the condition, check out The Mighty’s CMT community and share your story!
References (click to expand)
- Muscular Dystrophy Association. (2015, December 17). Charcot-Marie-Tooth Disease (CMT). Retrieved from Muscular Dystrophy Association website: https://www.mda.org/disease/charcot-marie-tooth
- National Institute of Neurological Disorders and Stroke. (2018, August 13). Charcot-Marie-Tooth Disease Fact Sheet. Retrieved from https://www.ninds.nih.gov/Disorders/Patient-caregiver-education/Fact-sheets/Charcot-Marie-Tooth-Disease-Fact-Sheet#3092_4
- National Organization for Rare Disorders. (n.d.). Charcot-Marie-Tooth Disease. Retrieved from NORD (National Organization for Rare Disorders) website: https://rarediseases.org/rare-diseases/charcot-marie-tooth-disease/