Peripheral Neuropathy - Charcot-Marie-Tooth Disease

Question 1

What is Charcot-Marie-Tooth Disease?

Answer 1

An inherited (mostly autosomal dominant) disease that affects the peripheral motor (more) and sensory neurones by causing dysfunction in the myelin or the axons.

Question 2

Epidemiology of Charcot Marie Tooth Disease (2).

Answer 2

1. Commonest hereditary peripheral neuropathy.

2. Symptoms can begin around 10 with feet and progress to hands later.

Question 3

Types of Charcot-Marie-Tooth Disease (2).

Answer 3

1. Type I : Demyelinating Condition (commoner).

2. Type II : Axonal.

Question 4

Aetiology of Peripheral Neuropathy (5).

Answer 4

ABCDE :
A : Alcohol.
B : B12 Deficiency.
C : Cancer or CKD.
D : Diabetes or Drugs.
E : Every Vasculitis.

Question 5

Give 3 Drugs that can cause Peripheral Neuropathy.

Answer 5

1. Isoniazid.
2. Amiodarone.
3. Cisplatin.

Question 6

Clinical Features of Charcot-Marie-Tooth Disorder.

Answer 6

1. Pes Cavus (High-Foot Arches).
2. Inverted Champagne Bottle legs (Distal Muscle Wasting) / Stork Leg Deformity.
3. Weakness in Lower Legs (mainly Ankle Dorsiflexion).
4. Weakness in Hands.
5. Reduced Tendon Reflexes.
6. Reduced Muscle Tone.
7. Peripheral Sensory Loss.

Question 7

Suspicion of Charcot-Marie-Tooth Disease.

Answer 7

Frequently Sprained Ankles.

Question 8

Investigations of Charcot-Marie-Tooth Disease (2).

Answer 8

1. Nerve Conduction Studies - Reduced Conduction Velocity in Type I (not Type II).
2. Genetic Testing.

Question 9

Management of Charcot-Marie-Tooth Disorder (4).

Answer 9

SUPPORTIVE (no Curative) :

1. Physiotherapy : Maintain Muscle Strength and Joint Range of Motion.
2. Occupational Therapy.
3. Podiatry : Foot Symptoms e.g. Insoles and Orthoses.
4. Orthopaedic Surgerons : Correct Disabling Joint Deformities.