Multiple sclerosis Flashcards
Describe the pathophysiology of MS
Inflammatory plaques of demyelination in the CNS disseminated in time and space (occurring at multiple sites with >30days between attacks)
Demyelination heals poorly, eventually causing axonal loss
What causes MS?
Unknown
Environment plus genetics
Vitamin D deficiency
What is the mean age of onset of MS
30yo
Which gender does MS affect more?
Females
3:1 F:M
Describe the presentation of MS
Monosymptomatic
20% present with unilateral optic neuritis
Corticospinal tract
Sensory - dysesthesia, pins and needles decreased vibration sense, trigeminal neuralgia
Motor - Spastic weakness, myelitis
Sexual/GU - bladder involvement, erectile dysfunction, urine retention, incontinence, anorgasmia
GI - swallowing, constipation
Eye - diplopia, hemianopia, optic neuritis, visual phenomena, bilateral internuclear ophthalmoplegia, pupil defects
Cerebellum - trunk and limb ataxia, intention tremor, scanning, falls, speech
Cognitive and visuospatial decline
What may exacerbate symptoms of MS?
Heat - baths and exercise
What tests may be done to diagnose MS
MRI - sensitive but not specific for plaque detection
CSF - oligoclonal bands of IgG on electrophoresis that are not present in the serum, suggest CNS inflammation
Evoked potentials - delayed visual acuity, auditory and somatosensory evoked potentials
Which criteria is used to diagnose MS
McDonald criteria
Describe the evidence needed for diagnosis of MS in the McDonald criteria
Evidence of dissemination in time and space plus clinical presentation. >2 attacks and >2 objective clinical lesions
Describe the progression of MS
Relapsing remitting course with initial recovery in between relapses
With time, remission becomes incomplete and so disability accumulates
List some poor prognostic signs
Older age Male Motor signs at onset Many early relapses Many MRI lesions Axonal loss
Describe the effect of pregnancy on MS
Does not alter the rate of progression
Relapses may reduce during pregnancy and increase 3-6months after, but return to their previous rate thereafter
Describe the management of MS
Lifestyle
Disease modifying drugs
Treat relapses
Symptom control
What lifestyle measures may be advised in the management of MS
Regular exercise, stopping smoking, avoiding stress
List some disease modifying drugs
Dimethyl fumarate
Alemtuzumab
Natalizumab
Describe alemtuzumab
Monoclonal antibodies
Act against T cells
Describe natalizumab
Monoclonal antibodies
Acts against VLA4 receptors that allow immune cells to cross the blood brain barrier
What drug is given to treat relapses
Methylprednisolone 0.5-1g/24h/IV/PO for 3-5days shortens acute relapses
Use sparingly
Does not alter overall prognosis
Which drugs are given to treat spasticity
Baclofen Gabapentin Tizanidine Dantrolene Benzodiazepines
Which drugs are given to treat tremor
Botulinum toxin type A injections
Which drugs are given to treat urinary urgency/frequency
Self catheterization if >100ml residual volume
Tolterodine if <100ml residual volume
What may help treat fatigue in MS
CBT
Amantadine
Exercise
List some MS eponyms
Devic's syndrome Lhermitte's sign Uhthoff's phenomenon Charles Bonnet syndrome Pulfrich effect Argyll Robertson pupil
Describe devic’s syndrome
MS variant with transverse myelitis - loss of motor, sensory, autonomic reflex and sphincter function below the level of the lesion
Optic atrophy
Anti-aquaporin 4 antibodies
Describe Lhermitte’s sign
Neck flexion causes electric shocks in trunk/limbs
What conditions is Lhermitte;s sign seen in?
MS
Cervical spondylosis
Cord tumours
B12 deficiency
Describe Uhthoff’s phenomenon
Worsening of symptoms with heat
Describe Charles bonnet syndrome
Decreased acuity/temporary blindness with complex visual hallucination of faces, shapes and animals
Describe Pulfrich effect
Unequal eye latencies, causing disorientation in traffic as straight trajectories seem curved and distances are misjudged on looking sideways
