NEUROLOGY Flashcards
What is MS?
chronic and progressive condition that involves demyelination of the myelinated neurones in the central nervous system (affects the white matter of the brain and spinal cord).
Inflammatory process involving activation of the immune cells against myelin.
What type of hypersensitivity reaction is MS?
Type 4 - T cell mediated
When does MS present?
Young adults <50 years
Women
Which types of cells provide myelin?
Schwann cells (peripheral nervous system) Oligodendrocytes (central nervous system)
Which myelin producing cells are mostly affected in MS?
Oligodendrocytes
Name 5 causes of MS.
Genetic EBV Low vitamin D Smoking Obesity
When might MS symptoms improve?
Pregnancy
Postpartum period
How do you describe the frequency of MS symptoms?
Disseminated in time and space
Name five different ways that MS can present.
Optic neuritis Eye movement abnormalities Focal weakness Focal sensory symptoms Ataxia
How long does first-presentation of MS usually last?
Symptoms progress over 24 hours
Lasts days-weeks and then improves
What is the most common presentation of MS?
Optic neuritis (demyelination of the optic nerve)
Which cranial nerve is commonly affected in MS?
CN 6 - abducens
How does a CN6 lesion present?
Internuclear ophthalmoplegia
Conjugate lateral gaze disorder
Give some examples of focal weakness in MS.
Bell’s palsy
Horner’s syndrome
Limb paralysis
Incontinence
Give some examples of sensory symptoms in MS.
Trigeminal neuralgia
Numbness
Paraesthesia (pins and needles)
Lhermitte’s sign - electric shock sensation that travels down the spine when flexing the neck
What is Lhermitte’s sign?
Lhermitte’s sign is an electric shock sensation that travels down the spine and into the limbs when flexing the neck. It indicates disease in the cervical spinal cord in the dorsal column. It is caused by stretching the demyelinated dorsal column.
Name two types of ataxia that are seen in MS.
Sensory ataxia - loss of proprioceptive sense (results in positive Romberg’s test)
Cerebellar ataxia - suggests cerebellar lesions
Name four types of disease patten in MS.
Clinically isolated - may never progress to MS
Relapsing-remitting -
Secondary progressive
Primary progressive
Which is the most common disease patten seen in MS?
Relapsing-remitting
What is meant by active or not active MS?
Active = new symptoms or lesions are developing
Not active = no new symptoms or lesions are developing
What is meant by worsening or not worsening MS?
Worsening = overall disability is worsening over time
Not worsening = there is no worsening of disability over time
Describe the disease pattern seen in secondary progressive MS.
Initially relapsing-remitting.
Then progressive worsening of disability over time.
What is primary progressive MS?
The disease progressively worsens overtime without relapse or remission.
How does optic neuritis present?
Central scotoma
Pain on eye movement
Impaired colour vision
Relative afferent pupillary defect
Name 7 causes of optic neuritis.
Sardcoidosis SLE Diabetes Syphilis Measles Mumps Lymes disease
What is Uhthoff’s phenomenon?
Symptoms brought on by changes in temperature
What signs might be elicited in a patient with MS?
Reduced visual acuity
Weakness
Increased tone
Loss of proprioception
How is MS diagnosed?
Clinical picture - symptoms suggesting lesions change location
Other causes for the symptoms must be excluded
How is primary progressive MS diagnosed?
Symptoms must be progressive over a period of 1 year.
Which investigations can support the diagnosis?
MRI scans - demonstrate lesions
LP - oligoclonal bands
What type of MRI is requested in MS?
MRI contrast
FLAIR sequence can help distinguish non-specific white matter lesions.
How many lesions are expected to be seen on MRI investigating for MS?
One lesion per decade = normal
>1 lesions per decade = increased likelihood of MS
What investigation can be done to test nerve function in MS?
Evoked potential studies
What are the aims of MS treatment?
Induce remission - DMARDs
Treat relapses - methylprednisolone
How are relapses of MS treated?
Methylprednisolone 500mg for 5 days
1g IV for 3-5 days if oral treatment fails/relapse is severe
How are symptoms managed in MS?
Exercise - maintain activity and strength
Neuropathic pain - amitriptyline/gabapentin
Depression - SSRIs
Urge incontinence - oxybutynin
Spasticity - baclofen, gabapentin
Which medication is used to treat fatigue in MS?
Amantadine
What is the management of optic neuritis?
Urgent referral to ophthalmology
Steroids
2-6 weeks recovery
50% of patients will develop MS in the next 15 years
What is GBS?
Acute paralytic polyneuropathy
Causes demyelination of the peripheral nervous system
Usually triggered by an infection
Which infections are associated with GBS?
Campylobacter jejuni
Cytomegalovirus
EBV
What is the pathophysiology of GBS?
Molecular mimicry: B cells target antibodies on the pathogen, which are similar to antigens on the myelin sheath of motor neurons.
How does GBS present?
Ascending symmetrical weakness
Reduced reflexes
Peripheral loss of sensation or neuropathic pain
May progress to facial nerves and cause facial weakness
When do patients present with GBS?
4 weeks after preceding infection
How long is the recovery period for GBS?
Months - years
How long is the recovery period for GBS?
Months - years
How is GBS diagnosed?
Clinically: Brighton criteria
Which investigations support the diagnosis of GBS?
Nerve conduction studies
Lumbar puncture
What might be seen on a LP in GBS?
Raised protein, normal cell count
What is the management of GBS?
IV IG
Plasma exchange
Supportive care
VTE prophylaxis
What is the leading cause of death in GBS?
PE
Respiratory failure
What is the prognosis in GBS?
80% fully recover
15% left with some neurological disability
5% will die
Name some differentials for degenerative myelopathy.
Compressive myelopathy (cancer, trauma) Peripheral neuropathy (diabetes) Infectious myelitis Anterior spinal artery occlusion = sensory, motor Posterior spinal artery occlusion = proprioception, vibration
How do patients present with myelopathy?
Neck pain
Loss of motor function (digital dexterity)
Loss of sensory function
Loss of autonomic function (urinary or faecal incontinence and/or impotence)
Hoffman’s sign
What is Hoffman’s sign?
Hoffman’s sign: is a reflex test to assess for cervical myelopathy. It is performed by gently flicking one finger on a patient’s hand. A positive test results in reflex twitching of the other fingers on the same hand in response to the flick.
What investigation is needed for myelopathy?
MRI cervical spine
What is the management of myelopathy?
Spinal decompression surgery: laminectomy
What is a seizure?
Transient episodes of abnormal electrical activity in the brain.
Name 6 different types of seizure.
Tonic-clonic Focal seizures Absence Atonic Myoclonic Infantile spasms
Where do focal seizures typically start?
Temporal lobes
Name 5 differentials for epileptic seizures.
Syncope: - Vaso-vagal - Cardiac - Orthostatic Non-epileptic seizures: - Psychogenic - Hypoglycaemic
When do generalised seizures usually present?
< 30 years
How do clonic-tonic seizures present?
Loss of consciousness
Tonic (muscle tensing)
Clinic (muscle jerking)
Typically the tonic phase comes before the clonic phase
There may be associated tongue biting, incontinence, groaing and irregular breathing
What is a post-ictal period? What symptoms are experienced?
Confusion, drowsy, irritable or depressed
How can focal seizures present?
Temporal - deja-vu, lip-smacking, auditary hallucinations
Parietal - sensory changes
Occipital - visual
Frontal - jacksonian march
What are simple and complex focal seizures?
Simple = with consciousness Complex = without consciousness
How do absence seizures present?
Blank, staring into space
Typically present in children
Last 10-20 seconds
How do atonic seizures present?
‘Drop attacks’
< 3 minutes
May be indicative of Lennox-Gastaut syndrome
How do myoclonic seizures present?
Sudden brief muscle contractions
Remains conscious
Typically in juvenile myoclonic epilepsy
What is West syndrome?
Infantile spasms
Starts around 6 months of age
Clusters of full body spasms
Poor prognosis (1/3 die by age of 25)
What investigations can help support a diagnosis of epilepsy?
EEG
MRI - structural pathology
What investigations can help exclude other causes of seizures?
ECG
Bloods - FBC, BMs, serum prolactin (true seizure)
Which patients require imaging following a seizure?
Over 25 and new onset
Focal
What is the aim of treatment for epilepsy?
To be seizure free on the minimum dose of anti-epileptic dose
What is the management for a first-time unprovoked seizure?
No treatment needed
What is the management for a second unprovoked seizure (tonic-clonic)?
Anti-convulsive monotherapy: sodium valproate (1st line)
Second line: lamotrigine or carbamazepine
What is the management of focal seizures?
First-line: carbamazepine or lamotrigine
Second-line: sodium valproate or levetiracetam
What is the management of absence seizures?
Typically stop in adulthood
First-line: sodium valproate or ethosuximide
What is the management of atonic seizures?
First-line: sodium valproate
Second-line: lamotrigine
What is the management of myoclonic seizures?
First-line: sodium valproate
Second-line: lamotrigine, levetiracetam or topiramate