Multiple sclerosis Flashcards
What is multiple sclerosis?
A cell-mediated autoimmune condition characterised by repeated episodes of inflammation of the nervous tissue in the brain and spinal cord resulting in loss of insulating myelin sheath
Aetiology of MS?
Greater incidence in females (3:1)
Presents typically between 20 to 40 years of age.
More common in white populations and with increasing distance from the equator.
Causes of MS not completely understood but autoimmune process appears to be caused both by genetic and environmental factors. Some genes include HLA and MHC polymorphisms.
What factors indicate a worse prognosis for MS?
Older
Male
Motor signs at onset
Early relapses
Many MRI lesions
Axonal loss
Pathophysiology of MS?
T cell mediated autoimmune disease that causes inflammatory process mainly within white matter of brain and spinal cord.
Plaques of demyelination occur anywhere in CNS white matter but have a preference for certain sites including:
- Optic nerves
- Brainstem + cerebellar connections
- Cervical cord (corticospinal tract + posterior columns).
Patterns of MS?
Relapsing-remitting MS (most common 85-90%)
Secondary progressive MS
Primary progressive MS (10-15%)
What is the definition of a relapse in MS?
The appearance of new symptoms, or the return of old symptoms, for a period of 24 hours or more – in the absence of an infection or a change in your core body temperature.
What is relapsing-remitting MS?
Symptoms occur in attacks (relapses) with a characteristic time course: onset typically occurs over days and recovery (whether partial or complete) occurs overs weeks.
What is primary progressive MS?
Occurs in 10-15% of cases
Characterised by gradually worsening disability without relapses or remission.
What is secondary progressive MS?
A late stage of MS consisting of gradually worsening disability progressing over years.
Around 75% of patients with relapsing-remitting MS will progress to secondary progressive by 35 years from onset.
Relapse vs pseudorelapse?
A relapse is considered any new or acutely worsening neurological symptoms with objective evidence that: last more than 24 hrs, not related to infection, fever or other stresses and has no other explanation.
A pseudorelapse is a temporary worsening of symptoms without actual myelin inflammation or damage, brought on by other influences e.g. fatigue, overexertion, fever and infection.
Pyramidal dysfunction features of MS?
Increased tone (hypertonia)
Spasticity
Weakness
Affects extensors of upper limbs and flexors of lower limbs.
Optic neuritis features of MS?
Painful visual loss over 1-2 weeks - blurred vision in 1 eye and loss (or reduction) in colour vision.
RAPD (relative afferent pupillary defect - pupils react differently to light being shone on eye) will be present on affected side
Pale optic disc on affected side
Most improve
Sensory symptoms of MS?
Pain
Paraesthesia (abnormal sensation i.e. tingling)
Dorsal column loss (fasciculus gracilis and cuneatus) - proprioception and vibration
Numbness
Trigeminal neuralgia
Lower urinary tract dysfunction in MS symptoms?
Increased frequency and urgency
Nocturia (urinaration at night)
Urge incontinence
Retention
Brainstem (cranial nerve palsy) dysfunction in MS symptoms?
Diploplia (double vision) - CN 6 palsy
Facial weakness - CN 7 palsy
Fatigue in MS symptoms?
Physical and cognitive
Sense of exhaustion
Investigations for MS?
Bloods
- Before neurological referral, exclude differential diagnoses by checking FBC, inflammatory markers, U+E’s, LFT’s etc.
Neurophysiology
- Can detect demyelination in apparently unaffected pathways with characteristic delays.
MRI
- Periventricular lesions
- Discrete white matter abnormalities
CSF
- Oligoclonal bands present in 90+% of cases - distinct bands of IgG on western blot that are unmatched with serum testing.
Management of acute relapse?
Mild - symptomatic treatment
Moderate - oral steroids
Severe - admit/IV steroids
Symptomatic treatment for pyramidal dysfunction?
Physioterapy
Occupational therapy
Anti-spasmodic agent e.g. oral baclofen, botulinum toxin.
Symptomatic treatment for sensory symptoms?
Anticonvulsants i.e. gabapentin
Antidepressants i.e. amitriptyline
Acupuncture
Symptomatic treatment for lower urinary tract dysfunction?
Bladder drill
Desmopressin
Anti-cholinergics e.g. oxybutynin
catheterisation
Symptomatic treatment for fatigue?
Amantadine
Modafinil (if sleepy)
Hyperbaric oxygen
Red colour desaturation is a buzzword for what?
Optic neuritis
Most common presentation (associated ocular condition) of MS?
Optic neuritis
What is optic neuritis?
involves demyelination of the optic nerve and presents with unilateral reduced vision, developing over hours to days.
Key features of optic neuritis?
Central scotoma (an enlarged central blind spot)
Pain with eye movement
Impaired colour vision
Relative afferent pupillary defect
What is RAPD?
Relative afferent pupillary defect
where the pupil in the affected eye constricts more when shining a light in the contralateral eye than when shining it in the affected eye.
When testing the direct pupillary reflex, there is a reduced pupil response to shining light in the eye affected by optic neuritis.
Some other causes of optic neuritis?
Sarcoidosis
Systemic lupus erythematosus
Syphilis
Measles or mumps
Neuromyelitis optica
Lyme disease
For optic neuritis, patients presenting with acute loss of vision need urgent ophthalmology input. true/false?
True
Treatment of optic neuritis?
High dose steroids i.e. prednisolone
What determines which patients with optic neuritis will go on to develop MS?
Changes on an MRI scan
Focal weakness symptoms of MS?
Incontinence
Horner syndrome
Facial nerve palsy
Limb paralysis
Focal sensory symptoms of MS?
Trigeminal neuralgia
Numbness
Paraesthesia (pins and needles)
Lhermitte’s sign
What is Lhermitte’s sign in MS?
a sudden brief pain or electrical buzzing sensation. It runs down your neck into your spine and might then spread into your arms or legs.
Can be described as an “electrical shock” sensation in some patients.
Signs of MS in MRI of head and spinal cord?
Juxtacortical and paraventricular lesions, in addition to spinal cord lesions.
What is internuclear ophthalmoplegia?
Presents with ipsilateral impairment of the adducting eye and nystagmus of the abducting eye.
Multiple sclerosis is particularly a cause in younger patients.
Horner syndrome can have an association with MS. What are the triad of symptoms for Horner’s?
Triad of:
partial ptosis (upper eyelid drooping)
anhidrosis (complete absence of sweating)
miosis (excessive constriction of pupil)
