Funny name…serious disease: so what’s wrong with you?

What would it be like to walk into a pub, order a beer and be refused because you are a bit wobbly on your feet? How would you feel if you were refused a beer because someone thought you were drunk rather than had Charcot-Marie-Tooth: a funny name but a serious disease.

My partner has Charcot-Marie-Tooth (CMT). He is a bit wobbly on his feet and permanently uses a single long arm crutch. He regularly gets asked: What sort of accident did you have? Or where is your other crutch? Sometimes people talk to him very slowly and loudly. He has a PhD in political science from UNSW, teaches and does research. He does have a serious disease, with a funny name, that hinders and frustrates him but so do about 1 in every 2 500 Australians. Some people might be a bit wobbly and not even know they have CMT.

It is CMT awareness month, so here is some awareness about CMT.

CMT is a group of genetic disorders characterised by a dysfunction of peripheral nerves that impact on motor skills and cause sensory impairment. It perhaps feels like the floor is constantly moving and you can't quite get in time with that movement. It is perhaps also like you can feel things with you hands and feet but there is a delay, you feel it moments afterwards rather than straight away (not good if you put your foot in a bath that's too hot or a stove top that is still on).

There is no cure for CMT. It is genetic. Most CMT people will live a long life with the disease, even if it drives them crazy in explaining what CMT means. CMT was first identified in 1886 by Jean-Martin Charcot and Pierre Marie in France and Howard Henry Tooth in London in 1889; hence the funny name.

Being a genetic disease you need DNA testing to confirm you have it and to find out what type you have. DNA testing is increasingly becoming cheaper, so the medico's tell us that it is more than likely more people with be diagnosed with CMT. Some European studies are pointing to the likelihood that globally one in 1000 people have CMT.

There are at least 15 different types of CMT; some are mild, some are particularly burdensome. The most common form of CMT is Type 1A (60 per cent). The mean age of the onset of symptoms is 22. The mean age of diagnosis is 34 (with 29 per cent of people with CMT having been misdiagnosed). It is diagnosed in children and adults and affects all ethnic groups. Ideally, genetic counseling is available to parents who fear that they may pass their CMT causative genes to their children. This is the most effective way to eradicate this disease. 

CMT is caused by changes in any one of a number of genes that carry the instructions on how to make the peripheral nerves. As a disorder of the peripheral nervous system, it affects how the nerves throughout the body communicate motor and sensory information to and from the spinal cord.

As such, it is a disease that affects the extremities of the body. Most CMT people have lower limb weakness (95 per cent), impaired gait (68 per cent), decreased or absent deep tendon reflexes (86 per cent), pes cavus (70 per cent) and hammer toes (46 per cent): all of which means they walk a bit different, wobble sometimes badly, or are in a wheelchair.

Severity of symptoms is variable in different patients and even among family members with the disease. Progression of symptoms is gradual. Pain can range from mild to sever.

Some CMT people have surgeries on backs, legs and feet to maintain their mobility. Many CMT people have spinal deformities. In some cases CMT people have trouble sleeping because of sleep apnea. The suffer fatigue and daytime sleepiness. Sometimes, like my partner, they get grumpy because they haven't slept well.

There are considerable diagnostic, symptomatic and ethical issues associated with CMT, particularly in relation to DNA testing, pregnancy and young people.