Dejerine-Sottas Disease (DS), also known as CMT type 3, is an inherited peripheral neuropathy that typically begins in infancy.
Understanding Dejerine-Sottas Disease
Definition
Dejerine-Sottas Disease (DS) is a severe form of Charcot-Marie-Tooth disease (CMT), a group of disorders affecting the peripheral nerves. DS is characterized by its early onset and significant impact on motor and sensory functions.
Key Features
Here's a breakdown of the key aspects of DS:
- Inherited Disorder: DS is passed down through families, meaning it's genetic in origin.
- Peripheral Neuropathy: This means that the disease affects the nerves outside of the brain and spinal cord.
- Onset in Infancy: Unlike some other forms of CMT, DS typically presents in early childhood, often during infancy.
- Myelin Defect: The disease arises from defects in the genes that produce myelin, the protective covering around nerve fibers. This damage impairs the proper transmission of nerve signals.
- Severe and Progressive: DS is characterized by severe and progressive symptoms, meaning the condition gets worse over time.
- Weakness and Sensory Loss: Symptoms include significant weakness, often in the limbs, along with a loss of sensation.
Symptoms
- Severe muscle weakness
- Sensory loss
- Delayed motor development
- Impaired reflexes
- Gait abnormalities
- Possible muscle atrophy
Genetic Basis
The core issue in DS stems from gene mutations related to myelin production.
- Mutations affect the genes necessary for making myelin.
- Damaged myelin impairs the efficient transmission of nerve signals.
- This leads to the progressive neurological issues characteristic of DS.
Diagnosis
- A clinical evaluation by a neurologist, focusing on symptoms, and family medical history.
- Nerve Conduction Studies (NCS) to measure nerve signal speed.
- Electromyography (EMG) to assess muscle activity.
- Genetic Testing, to identify specific gene mutations.
Management
- There is no cure for DS, treatments concentrate on symptom management.
- Physical therapy to improve muscle strength and mobility.
- Occupational therapy to improve daily living skills.
- Orthotics, braces, and assistive devices to support mobility.
- Pain management as needed.
Example
For example, an infant with DS might display difficulty with basic motor milestones, have weak muscle tone, or display reduced reflexes in comparison to other children the same age. As the disease progresses, these children could experience significant challenges with walking, coordination, and other sensory functions.
