DISEASE- multiple sclerosis Flashcards
what is MS
a chronic autoimmune condition that involves demyelination of the myelinated nerves of the CNS
what cells wrap themselves around the axons in the CNS and PNS producing myelin?
CNS- oligodendrocytes
PNS- Schwann cells
who is MS more commonly seen in?
middle aged women
(30s - 40s)
does MS affect the CNS or PNS
CNS
-oligodendrocytes
pathophysiology of MS
-Myelin (produced by oligodendrocytes in the CNS) helps electrical impulses move faster along the axon
-In MS there is inflammation around the myelin and infiltration of immune cells that causes damage to the myelin, affecting the way electrical signals move along the nerve
-CD4 mediate destruction of oligodendroglial cells and humoral response to myelin binding protein
-This causes symptoms
can remyelination occur
in early disease remyelination can occur and symptoms can resolve
in late disease remyelination is incomplete and symptoms gradually become more perminant
buzz word phrase for MS
plaques disseminated in space and time
what does ‘disseminated in space + time’ mean?
MS lesions vary in location over time and so different nerves can be affected and symptoms may change
subtypes MS?
-Relapsing remitting MS
-Secondary progressive MS
-Primary progressive MS
most common subtype MS
relapsing remitting MS
describe relapsing remitting MS
characterised by episodes of disease and neurological symptoms followed by recovery
describe secondary progressive MS
was relapsing remitting at first but now there is a progressive worsening of symptoms with incomplete remissions
symptoms become more and more permanent
describe primary progressive MS
worsening of disease and neurological symptoms from point of diagnoses without initial relapse and remission
who is MS more common in?
<50
Females (3x more common)
EBV
Low vit D
Smoking
Obesity
when may MS symptoms improve?
-in pregnancy and post partum period
presentation of MS?
Can really vary and at first presentation symptoms tend to last days/ weeks and then improve
-fatigue
-Optic neuritis (most common)
-Eye movement abnormalities
-focal weakness
-Focal sensory symptoms
-Ataxia
-Cognitive impairment
how many optic neuritis present?
Optic neuritis is one of the most common presentations and involves demyelination of the optic nerve
-painful vision loss in one eye
-Central scotoma (enlarged blind spot)
-Pain on eye movement
-Impaired colour vision
-RAPD
explain the eye movement abnormalities that may be experienced with MS
Can have lesions within CN6 (abducens) which lead to double vision
Can be either:
-internuclear opthalmoplegia
OR
-Conjugate lateral gaze disorder
Describe internuclear opthalmoplegia
Unilateral lesion affecting horizontal gaze
-unilateral lesion in the medial longitudinal fasciculus blocking the connection between the contralateral CNVI nucleus and ispilateral CNII nucleus
-Ipsilateral impaired adduction of eye + nystagmus on abduction
describe conjugate lateral gaze disorder?
Lesion in CN6
-basically CN6 palsy in one eye (cant abduct)
if lesion in left:
-try to move the left eye left, the right eye will still move left but the left eye will not
examples of focal weakness people with MS can experience?
-Bells palsy
-Horners syndrome
-Limb paralysis
-Lower urinary dysfunction
-Increased tone/spasticity/weakness
what nerve is affected in Bells palsy?
Facial nerve
how does Bells palsy present?
Unilateral LMN facial palsy :
-half the face will be weak/ droopy (with forehead involved)
-Some may lose taste in anterior 2/3 of tongue (chorda tympany innervates this)
what nerve chain is involves in Horners?
sympathetic
presentation of Horners?
Triad of:
-Ptosis
-Miosis
-Anhydrosis (lack of sweating)
How to tell if pre, central or post ganglionic lesion in horners?
Pre ganglionic lesion:
-Anhydrosis of face
Central lesion:
-anhydrosis of face, arms and trunk
Post ganglionic lesion:
-No anhydrosis
what will commonly cause a central lesion in Horners syndrome and how may this present?
Presents as miosis, ptosis and anhydrosis of face, trunk and arms
Central lesion- 4S:
Stroke
MS
SOL (tumours)
Syringomyelia
(pre ganglionic chain arises from spinal cord in the chest, central arises from base of neck and post ganglionic arises from the head)
what will commonly cause a pre ganglionic lesion and how does it present - Horners
Pre ganglionic:
Miosis, ptosis and anhydrosis in facr
4 Ts:
T – Tumour (Pancoast’s tumour)
T – Trauma
T – Thyroidectomy
T – Top rib (a cervical rib growing above the first rib above the clavicle)
(pre ganglionic chain arises from spinal cord in the chest, central arises from base of neck and post ganglionic arises from the head)
what will commonly cause a post ganglionic lesion and how does it present - Horners
Miosis, ptosis and NO anhydrosis
Post-ganglionic lesion (4 Cs):
C – Carotid aneurysm
C – Carotid artery dissection
C – Cavernous sinus thrombosis
C – Cluster headache
(pre ganglionic chain arises from spinal cord in the chest, central arises from base of neck and post ganglionic arises from the head)
what is Lhermitte’s sign?
Electric shock sensation that travels down spine and into limbs when flexing the neck
Caused by stretching demyelinated dorsal column
can be +ve in MS!!
what is Rombergs test?
Patient stands erect for 60 seconds
30 seconds with eyes open
30 seconds with eyes shut
+ve if they fall/ lose balance
can be +ve in MS!!
imaging of MS?
MRI
what will MRI show of someone with MS?
-Periventricular white matter lesions (around ventricle)
-Plaques of demyelination (disseminated in time and space)
what will LP show in MS?
-Oligocloncal bands in CSF
these are proteins that indicate inflammation of the CNS, produced by IgG
(not specific to MS- can be found in Lymes, SLE, neurosarcoid)
what criteria is used for diagnosis?
McDonald criteria
management of acute relapse?
Mild- symptomatic treatment
Moderate- Oral steroids (methylprednisolone 500mmg daily for 5 days)
Severe- admit, IV steroids + if they do not respond give plasma exchange
management of neuropathic pain
Amitryptiline
Gabapentin
management of urge inconctinence?
Anticholingergics (e.g. tolterodine or oxyfutynin)
however can cause cognitive impairement
management of spasticity?
-Baclofen (muscle relaxant)
-Gabapentin
-Physio
Fatigue- management?
OT is main treatment
what DMARDs are used in MS?
first line:
ORAL= dimethyl fumerate AKA Tecfidera
INJECTIBLE= interferon beta
