Multiple Sclerosis Flashcards
Describe some features of multiple sclerosis
Disease of young people, has variable severity, diverse presentation and the prognosis is uncertain
What is multiple sclerosis?
A central nervous system disease affecting the white matter
Demyelination (inflammation) causing focal disturbance of function
Most patients develop progressive disability
Describe the prevalence of multiple sclerosis
190 per 100000 in Scotland
50-60 cases per year in Aberdeen
What is the average age of onset for multiple sclerosis?
Around 20-30
Describe the pathogenesis of multiple sclerosis
Complex genetic inheritance and has association to autoimmune disease - more females to males
Commoner in temperate climate
What is the initial presentation of multiple sclerosis?
Relapse - demyelination
Inflammation which has gradual onset over days and stabilises days to weeks
Gradual resolution - partial or complete recovery
What are some symptoms of a relapse in multiple sclerosis?
Optic neuritis, sensory symptoms, limb weakness, brainstem - diplopia, vertigo/ataxia, spinal cord - bilateral motor and sensory symptoms and bladder involvement
Describe optic/ retrobulbar neuritis
Subacute visual loss, pain on moving eye, colour vision impaired, resolves over weeks/ months
Initial optic disc swelling, optic atrophy and relative afferent pupillary defect
What is a relative afferent pupillary defect?
Dark room, shin torch into eye and constriction
As swing to affected eye then they dilate
Swing light and they constrict
Describe a brainstem relapse
CN involvement
Pons - internuclear ophthalmoplegia
Cerebellum - vertigo, nystagmus and ataxia
UMN signs in limbs
Sensory involvement
What is left internuclear ophthalmoplegia?
Normal gaze to left
Gaze to right causes left eye to not abduct and nystagmus in right eye
What does a spinal cord lesion cause?
Partial or transverse (complete) myelitis
Sensory level is often with band of hyperaesthesia
Weakness/ UMN changes below demyelination
Bladder and bowel involvement
What is the process of demyelination?
Autoimmune process - activated T cells cross blood brain barrier causing demyelination
Acute inflammation of myelin sheath causing loss of function
Can demyelination repair?
Yes and can have recovery of function
Post inflammatory gliosis may be functional deficit
What is clinically isolated syndrome (CIS)?
When no further episodes of demyelination as MS is episodes of demyelination in space and time
Describe further relapes in MS
May occur within months or years of first episode
Variable site and severity
Is underlying infection in some
Fewer relapses in pregnancy
What does progression of MS cause?
Axonal loss - which contributes to persistent disability
Can see black holes on MRI
Later seen as cerebral atrophy
What are some progressive phase symptoms and signs?
Fatigue, temp. sensitivity, dysesthesia, stiffness or spasm, balance and slurred speech, bladder and bowel, diplopia/ visual loss, dysphagia and cognitive memory affected
What can be seen on examination of progressive MS?
Afferent pupillary defect, nystagmus, cerebellar signs, weakness, spasticity, hyperreflexia and plantars extensor
What are the types of MS?
Relapsing remitting (RRMS) 85%
Secondary progressive (SPMS)
Primary progressive (PPMS) 10-15%
Describe primary progressive MS
Often presents in 5th or 6th decade, no relapses, spinal and bladder symptoms
Prognosis is poor
How is MS diagnosed?
Evidence of demyelination separated in time and space
Can be clinical or MRI based
Posers criteria - clinical
How are active lesions seen on MRI?
Add Gadolinium to show active lesions - demyelination
What are some other investigations used in MS?
Lumbar puncture - normal CSF and protein but few WCC and oligoclonal bands present
CXR, Bloods, visual evoked response
