Charcot-Marie-Tooth Disease

Question 1

What is affected in Charcot-Marie-Tooth?

Genetics

Answer 1

Charcot-Marie-Tooth disease is an inherited peripheral neuropathy that is usually motor

There are various types of Charcot-Marie-Tooth with different genetic mutations and different pathophysiology.

Majority of mutations are inherited in an autosomal dominant pattern.

Question 2

Clinical Features

Answer 2

Symptoms usually start to appear before the age of 10 years but the onset of symptoms can be delayed until 40 or later.

Clinical features:

• High foot arches (pes cavus)
• Distal muscle wasting causing “inverted champagne bottle legs”
• Weakness in the lower legs, particularly loss of ankle dorsiflexion
• Weakness in the hands
• Reduced tendon reflexes
• Reduced muscle tone
• Peripheral sensory loss

Question 3

Management

Answer 3

Management is purely supportive with input from various members of the multidisciplinary team:

• Neurologists and geneticists to make the diagnosis
• Physiotherapists to maintain muscle strength and joint range of motion
• Occupational therapists to assist with activities of living
• Podiatrists to help with foot symptoms and suggest insoles and other orthoses to improve symptoms
• Orthopaedic surgeons to correct disabling joint deformities

Question 4

Diagnosis

Answer 4

Diagnosis is made with a combination of nerve conduction studies and genetic testing.

Patients with type 1 have reduced conduction velocity, whereas this is normal in type 2