[5] Multiple Sclerosis Flashcards
What is multiple sclerosis (MS)?
A cell-mediated autoimmune condition characterised by repeated episodes of inflammation of the nervous tissue in the brain and spinal cord
What is the result of the inflammation of the nervous tissue seen in MS?
Loss of the insulating myelin sheath
What cells are lost in MS?
Oligodendrocytes
What are oligodendrocytes responsible for?
Creating and maintaining the myelin sheath
What is the effect of MS on the myelin sheath?
Causes thinning and eventually complete loss
When may MS affect the axons of the neurons?
In advanced disease
What is the result of the loss of myelin in MS?
Less effective conduction of electrical signals
How is loss of myelin handled in early MS?
Remyelination occurs
Why is remyelination not involved later in MS?
It becomes less effective after repeated attacks and eventually scar-like plaques build up around the axon
What are the three main characteristics of MS?
- Formation of plaques in the CNS
- Inflammation
- Destruction of the myelin sheath
Does MS form plaques in the white or grey matter?
White matter
White matter in what parts of the nervous system are commonly affected in MS?
- Optic nerve
- Brain stem
- Basal ganglia
- Spinal cord
- Peri-ventricular
What cells cause the inflammation in MS?
T cells
What happens as a result of the inflammation caused by attack of the myelin?
Other immune cells are signalled and factors such as cytokines are released, worsening the problem
What are the three different patterns of MS?
- Relapsing-remitting
- Primary progressive
- Secondary progressive
What is the pattern of disease in relapsing-remitting MS?
The disease comes and goes with occasional irrecoverable loss of function in some relapses
What percentage of patients with MS have relapsing-remitting at first onset?
80%
What is secondary progressive MS?
Gradually worsening symptoms with fewer relapses that follows on from relapsing-remitting MS
What percentage of patients with relapsing-remitting MS go on to develop secondary progressive within first 10 years?
50%
What is primary progressive MS?
Gradually worsening symptoms from the beginning with no remission
What percentage of MS patients have primary progressive from onset?
10-15%
What factors can have an influence on the development of MS?
- Genetic factors
- Environmental e.g. early viral infections
What are the risk factors for MS?
- Family history
- Smoking
- Vitamin D deficiency
- Autoimmune disease
- EBV
What are the common initial features of MS?
- Loss of vision in one eye with painful eye movements
- Diplopia
- Ascending sensory disturbance and/or weakness
- Altered sensation down the back and sometimes into the limbs
What are the common features in the history in a patient presenting with MS?
- Often <50
- History of previous neurological symptoms
- Symptoms evolving over more than 24 hours
- Symptoms persisting and then improving after a few weeks
What neurological signs or symptoms can present in patients with MS?
Almost any
What are the more common types of neurological symptoms in MS?
- Autonomic
- Visual
- Motor
- Sensory
How can the main symptoms of MS be divided?
- Central
- Visual
- Speech
- Throat
- MSK
- Sensation
- Bowel
- Urinary
What are the central symptoms of MS?
- Fatigue
- Cognitive impairment
- Depression
- Anxiety
- Unstable mood
What are the visual symptoms of MS?
- Nystagmus
- Optic neuritis
- Diplopia
Why is optic neuritis an important symptom in MS?
It is often a first presenting symptom
Give one speech and one throat symptom of MS?
- Dysarthria
- Dysphagia
What are the MSK symptoms of MS?
- Weakness
- Spasms
- Ataxia
What are the sensation symptoms of MS?
- Pain
- Hypoesthesia
- Paraesthesia
What are the bowel symptoms of MS?
- Incontinence
- Diarrhoea and constipation