Multiple Sclerosis (MS) Flashcards
Define Multiple Sclerosis (MS) & it’s potential causes
Inflammatory condition of CNS
Discrete plaques of demyelination occurs at multiple sites due to T-Cell mediated immune responce
Cause: Unknown
- Further from equator = Inc incidence & prevalence!
- Childhood exposure to sunlight/ vit D reduces risk/ severity of MS
- Children <15 aquire the risk of where they settle [migration studies]
- Genetic component?
- HLA Chromodome 6
- 30%: MZ twins, 15% DZ twins
- Viral: EBV? (low evidence)
- Trauma triggering MS?
Outline the prevelence, sex distribution & age of onset of MS
- Further from equator = inc prevalence & incidence
- England 42/100k
- Scotland 200/100k
- Lifetime UK risk 1/1k
- Women 3:1 Men
- 30yrs = avg age of onset
Outline the common presentations of MS
Inc Symptoms & Signs
-
Unilateral Optic Neuritis
- Pain on movement
- Rapid dec central vision
- Red desaturation
- Signs: Marcus Gunn pupil
-
Brainstem/ Cerebellum
- Cerebellar signs
- Trunk/ limb ataxia
- Intention tremor
- Scanning speech
- Falls
- Brainstem signs
- Long-tract (myelopathy) signs
- Cranial nerve lesions [taste, smell, balance, hearing]
- Cerebellar signs
-
Spinal Cord [often worse 1 side]
- Numbness & paraesthesia
- Weakness
- Transverse myeltis [motor + sensory loss of both legs + bowels + bladder]
- Autonomic
- Neurogenic bladder
- Bowel problems
- Sexual problems
-
Rarer
- Hemiparesis (sub-cortical)
- Seizures
- Psychiatric symptoms (depression)
What is a Marcuss Gunn pupil?
**Marcus Gunn Pupil **aka Relative Afferant Pupil Defects
- Both pupils respond individually to light/ dark
- Swinging Light Test
- Light on 1 side [constrict to small size] then move light to other side [when light hits it should constrict again]
- RAPD: …then move light to other side [pupil continues to dilate dispite light hitting it]
https://www.youtube.com/watch?v=HSYo7LhfV3A
Outline the diagnosis criteria for MS
McDonald critera for diagnosing MS (2010)
Simplistically, you need 2 disseminations of time and 2 disseminations in space
- Time
- Attacks at different times
- MRI evidence
- Space
- Attack at new site
- MRI evidence
- +CSF & MRI: 2+ lesions consistent of MS
Clinical presentations & steps needed for diagnosis
- 2:2 - 2+ attacks & 2+ objective clinical lesions
- Nothing more required [imaging desirable: must conform to MS]
- 2:1 - 2+ attacks & 1 lesion
- MRI: dissemination in space
- +CSF & 2+ MRI: typical MS lesions
- 2nd attack at new site
- 1:2 - 1 attack & 2+ lesions
- MRI: dissemination in time
- 1:1 - 1 attack & 1 lesion [monosymptomatic presentation]
- Dissemination in space: MRI OR +CSF & 2+ MRI: typical MS lesions
- AND Dissemination in time: MRI or 2nd attack
- Insidious neurological progression (primary progressive MS)
- +CSF
- Dissemination in space: MRI
What MRI findings may be present in MS?
MRI abnormalities;
- Periventricular lesions [95%}
- Discrete white matter abnormalities [90%]
- Focal demyelination: Plaques
- Active or inactive: contrast agents
What findings in CSF may be present in MS?
Rise in total protein, normal glucose
<50 WCC/mL
Increase Oligoclonal bands of IgG on electrophoresis [not present in serum]
What are Evoked Potentials (EP) and what findings are present in MS?
Electrical potential recorded via nervous sytem following presentation of a stimulus
-
Delayed Evoked Potentials
- **Visual **[VEP common test]
- Auditory
- Somatosensory
What are prognostic factors for MS?
Worse if;
- Older male
- Motor signs at onset
- Many relapses early on
- Many MRI lesions [plaques[
- Axonal loss
Outline the different progressions of MS
-
Relapsing & Remitting
- Attacks come & go
- Accumulation of disability
-
2ndary Progressive
- Often from R&R [19yrs]
- Over 6months massive accumulation of disability
-
Primary Progressive [10%]
- Over 6 months massive accumulation of disability
- Middle aged men
- Untreatableish
- **Relapsing Progressive **[5-10%]
- Attacks as freqent as R&R
- Accumulation of disability as Primary Progressive
Outline the management of MS
(not symptomatic/ palliation)
Acute Relapses
-
Methylprednisolone
- ½-1g /24hr IV/PO for <3d
- No more than 2x/year
- Risks;
- Glucose levels
- Psyhosis
- GI bleed [give PPI]
- Avascular necrosis of femoral head
Disease Modifying Therapy [↓relapses]
-
Interferons [-1B & 1a] [mainly R&R]
- ↓Relapses by 1/3 in R&R
- ↓Lesion accumulation on MRI
- Does not delay disability/ affect prognosis
-
Monocloncal ABs [mainly R&R]
- Alemtuzumab: acts against T-cells in R&R
-
Natalizumab: acts again VLA-4 receptors that allow immune cells to cross BB barrier
- ↓Relapses by 2/3 in R&R
- Glatiramer (Copaxone) [mainly R&R]
- Mimics Myelin
- ↓Relapses by 1/3 in R&R
- Daily SC injection
- Mitoxantrone [mainly 2ndary progressive]
- Doxorubicin analogue
Outline the symptomatic/ palliative treatments available in MS
- Spasticity
- Sometimes mobility is dependent on spasticity..
- Baclofen (GABA agonist)
- Diazepam (benzo)
- Dantrolene (muscle relaxant)
- Tizanidine (muscle relaxant)
- Tremor
- Botulinum toxin type A injectives
- Urinary/ frequency
- Post-micturition residual urine >100mL
- Intermittent self-catheterization
- … <100mL
- Tolterodine Tolteerodine (antimuscarinic)
- Post-micturition residual urine >100mL
What is Transverse Myelitis?
Loss of motor, sensory, autonomic, reflex and sphincter function below level of lesion
What is Devic’s syndrome?
Outline;
- Defintion
- Diagnosis
- Treatment
Devic’s syndrome aka **Neuromyelitis Optica (NMO) **aka Opticospinal MS
- Recurrent & simultaneous Optic Neuritis & Transverse myelitis + NMO-IgG
- Long spinal cord lesion through 3+ vertebral segments in length
- Brain MRI lesion atypical for MS
- Diagnosis
- NMO-IgG
- Treatment
- IV steroids
- Plasma exchange therapy
- Immunosppressive for relapses
What is Lhermitte’s sign?
When is it found?
Lhermitte’s sign; neck flexion causes ‘electric shocks’ in trunks/ limbs
Found in;
- MS
- Cervical spondylosis
- Cord tumours
- Subacute combined degeneration of the cord (↓B12)
