Neurology Flashcards
Focal seizures
-What were these previously known as?
-where do these stem from in the brain
-how can these types of seizures be classified?
Focal seizures
previously termed partial seizures these start in a specific area, on one side of the brain the level of awareness can vary in focal seizures. The terms focal aware (previously termed 'simple partial'), focal impaired awareness (previously termed 'complex partial') and awareness unknown are used to further describe focal seizures further to this, focal seizures can be classified as being motor (e.g. Jacksonian march), non-motor (e.g. déjà vu, jamais vu; ) or having other features such as aura
Generalised seizures
-where do these stem from in the brain?
-give 5 types?
Generalised
these engage or involve networks on both sides of the brain at the onset
consciousness lost immediately. The level of awareness in the above classification is therefore not needed, as all patients lose consciousness
generalised seizures can be further subdivided into motor (e.g. tonic-clonic) and non-motor (e.g. absence)
specific types include:
tonic-clonic (grand mal)
tonic
clonic
typical absence (petit mal)
atonic
What is a focal to bilateral seizure?
Focal to bilateral seizure
starts on one side of the brain in a specific area before spreading to both lobes previously termed secondary generalized seizures
What is west’s syndrome aka
-What is this characterised by?
-What is seen on EEG?
-what can this be secondary to?
-What are possible treatments?
-What prognosis does this have?
Infantile spasms (West’s syndrome)
brief spasms beginning in the first few months of life
key features:
flexion of head, trunk, limbs → extension of arms (Salaam attack); last 1-2 secs, repeat up to 50 times
progressive mental handicap
EEG: hypsarrhythmia
usually secondary to serious neurological abnormality (e.g. tuberous sclerosis, encephalitis, birth asphyxia) or may be idiopathic
possible treatments include vigabatrin and steroids
has a poor prognosis
Absence seizures
-When do these onset?
-what are they characterised by?
-What is seen on EEG?
-What are treatment options?
-What prognosis do these have?
Typical (petit mal) absence seizures
onset 4-8 yrs duration few-30 secs; no warning, quick recovery; often many per day EEG: 3Hz generalized, symmetrical sodium valproate, ethosuximide good prognosis: 90-95% become seizure free in adolescence
Lennox-gastaut syndrome
-When do these onset?
-Give 4 clinical features
-What is seen on EEG
-What is the treatment?
Lennox-Gastaut syndrome
may be an extension of infantile spasms
onset 1-5 yrs
features:
atypical absences, falls, jerks
90% moderate-severe mental handicap
EEG: slow spike
treatment: ketogenic diet may help
What is benign rolandic epilepsy?
-Who is this most common in?
-What are the clinical features?
Benign rolandic epilepsy
most common in childhood, more common in males features: paraesthesia (e.g. unilateral face), usually on waking up
Juvenile myoclonic epilepsy
-What is the typical onset?
-What are 4 clinical features
-What is the treatment
Juvenile myoclonic epilepsy (Janz syndrome)
typical onset is in the teenage years, more common in girls
features:
infrequent generalized seizures, often in morning//following sleep deprivation
daytime absences
sudden, shock-like myoclonic seizure (these may develop before seizures)
treatment: usually good response to sodium valproate
Absence seizures:
-Who is this most commonly seen in?
-Who is affected?
Absence seizures (petit mal) are a form of generalised epilepsy that is mostly seen in children. The typical age of onset of 3-10 years old and girls are affected twice as commonly as boys
Give 4 clinical features of absence seizures
Features
absences last a few seconds and are associated with a quick recovery seizures may be provoked by hyperventilation or stress the child is usually unaware of the seizure they may occur many times a day
Describe the EEG pattern in absence seizures
EEG: bilateral, symmetrical 3Hz spike and wave pattern
What treatment in given first line for absence seizures?
What is the prognosis?
Management
sodium valproate and ethosuximide are first-line treatment good prognosis - 90-95% become seizure free in adolescence
When are anti-epileptics usually started?
Most neurologists now start antiepileptics following a second epileptic seizure.
NICE guidelines suggest starting antiepileptics after the first seizure if any of the following are present:
the patient has a neurological deficit brain imaging shows a structural abnormality the EEG shows unequivocal epileptic activity the patient or their family or carers consider the risk of having a further seizure unacceptable
What treatment is used for generalised tonic-clonic seizures?
-Males
-Females
Generalised tonic-clonic seizures
males: sodium valproate females: lamotrigine or levetiracetam girls aged under 10 years and who are unlikely to need treatment when they are old enough to have children or women who are unable to have children may be offered sodium valproate first-line
What is used first vs second line in focal seizures?
first line: lamotrigine or levetiracetam
second line: carbamazepine, oxcarbazepine or zonisamide
What is used first vs second line in absence seizures?
What may exacerbate absence seizures?
Absence seizures (Petit mal)
first line: ethosuximide
second line:
male: sodium valproate
female: lamotrigine or levetiracetam
carbamazepine may exacerbate absence seizures
What is used to treat myoclonic seizures?
Myoclonic seizures
males: sodium valproate females: levetiracetam
What is used to treat tonic or atonic seizures?
Tonic or atonic seizures
males: sodium valproate females: lamotrigine
How does sodium valproate work?
Sodium valproate is used in the management of epilepsy and is first-line therapy for generalised seizures. It works by increasing GABA activity.
Sodium valproate
-What can this cause to unborn fetus?
teratogenic
neural tube defects maternal use of sodium valproate is associated with a significant risk of neurodevelopmental delay in children guidance is now clear that sodium valproate should not be used during pregnancy and in women of childbearing age unless clearly necessary. Women of childbearing age should not start treatment without specialist neurological or psychiatric advice.
Give 11 side effects of sodium valproate in addition to teratogenicity?
P450 inhibitor
gastrointestinal: nausea
increased appetite and weight gain
alopecia: regrowth may be curly
ataxia
tremor
hepatotoxicity
pancreatitis
thrombocytopaenia
hyponatraemia
hyperammonemic encephalopathy: L-carnitine may be used as treatment if this develops
What is carbamazepine used for?
Carbamazepine is chemically similar to the tricyclic antidepressant drugs. It is most commonly used in the treatment of epilepsy, particularly partial seizures, where carbamazepine remains a treatment medication. Other uses include
trigeminal neuralgia bipolar disorder
What is the mechanism of action of carbamazepine?
Mechanism of action
binds to sodium channels increases their refractory period
Give 8 adverse effects of carbamazepine?
Adverse effects
P450 enzyme inducer dizziness and ataxia drowsiness headache visual disturbances (especially diplopia) Steven-Johnson syndrome leucopenia and agranulocytosis hyponatraemia secondary to syndrome of inappropriate ADH secretion
Why may patients see a return of seizures after 3-4 weeks of treatment?
Carbamazepine is known to exhibit autoinduction, hence when patients start carbamazepine they may see a return of seizures after 3-4 weeks of treatment.
Lamotrigine mechanism of action
Lamotrigine is an antiepileptic used second-line for a variety of generalised and partial seizures.
Mechanism of action
sodium channel blocker
What are the adverse effects of lamotrigine?
Adverse effects
Stevens-Johnson syndrome
What is the mechanism of action of phenytoin?
Phenytoin is used in the management of seizures.
Mechanism of action
binds to sodium channels increasing their refractory period
How can you divide the adverse effects of phenytoin?
Phenytoin is associated with a large number of adverse effects. These may be divided into acute, chronic, idiosyncratic and teratogenic. Phenytoin is also an inducer of the P450 system.
Give 7 acute adverse effects of phenytoin?
Acute
initially: dizziness, diplopia, nystagmus, slurred speech, ataxia later: confusion, seizures
Give 9 chronic adverse effects of phenytoin
Chronic
common: gingival hyperplasia (secondary to increased expression of platelet derived growth factor, PDGF), hirsutism, coarsening of facial features, drowsiness megaloblastic anaemia (secondary to altered folate metabolism) peripheral neuropathy enhanced vitamin D metabolism causing osteomalacia lymphadenopathy dyskinesia
give 6 idiosyncratic effects of phenytoin
Idiosyncratic
fever rashes, including severe reactions such as toxic epidermal necrolysis hepatitis Dupuytren's contracture* aplastic anaemia drug-induced lupus
Describe why phenytoin is teratogenic?
Teratogenic
associated with cleft palate and congenital heart disease
When should phenytoin levels be taken?
Phenytoin levels do not need to be monitored routinely but trough levels, immediately before dose should be checked if:
adjustment of phenytoin dose
suspected toxicity
detection of non-adherence to the prescribed medication
What are the mechanisms of action of topiramate?
Topiramate was developed as an antiepileptic and is used alone or as adjunctive treatment in generalised tonic-clonic seizures.
There appear to be multiple mechanisms of action:
blocks voltage-gated Na+ channels
increases GABA action
carbonic anhydrase inhibition: this results in a decrease in urinary citrate excretion and formation of alkaline urine that favours the creation of calcium phosphate stone
How can topiramate effect the contraceptives?
Topiramate is an inducer of the P450 enzyme CYP3A4. This may result in hormonal contraception being less effective. As a result, the Faculty of Sexual and Reproductive Health (FSRH) suggests the following for patients taking topiramate:
combined oral contraceptive pill and progestogen-only pill: UKMEC 3 (disadvantages outweigh advantages):
implant: UKMEC 2 (advantages generally outweigh the disadvantages)
The injection (Depo-Provera) and intrauterine system are not affected by topiramate.
Give 6 adverse effects of topiramate?
Adverse effects of topiramate include:
reduced appetite and weight loss
dizziness
paraesthesia
lethargy and poor concentration
rare but important: acute myopia and secondary angle-closure glaucoma
Topiramate is associated with a risk of foetal malformations.
what is the acute management of a prolonged seizure?
Rectal diazepam or oromucosal midazolam
What is the dose of rectal diazepam for:
-Neonate
-Child 1mth to 1 year
-Child 2yrs - 11yrs
-Child 12 yrs - 17 yrs
-Adult
-Elderly
Neonate 1.25 - 2.5 mg
Child 1 month - 1 year 5 mg
Child 2 years - 11 years 5 - 10 mg
Child 12 years - 17 years 10 mg
Adult 10 - 20 mg (max. 30 mg)
Elderly 10 mg (max. 15 mg)
What is the dose of oromucosal midazalam for:
-Neonate
-Child 1-2 mths
-Child 3-11mths
-Child 1-4yrs
-Child 5-9yrs
-Child 10-17 yrs
-Adult
Neonate 300 mcg/kg (unlicensced)
Child 1 - 2 months 300 mcg/kg (max. 2.5mg, unlicensced)
Child 3 - 11 months 2.5 mg
Child 1 - 4 years 5 mg
Child 5 - 9 years 7.5 mg
Child 10 - 17 years 10 mg
Adult 10 mg (unlicensced)
What is status epilepticus defined as?
Status epilepticus is defined as:
a single seizure lasting >5 minutes, or >= 2 seizures within a 5-minute period without the person returning to normal between them
What 4 antiepileptics should be prescribed by brand?
Phenytoin
Carbamazepine
Phenobarbital
Primodine
Describe migraine
Recurrent, severe headache which is usually unilateral and throbbing in nature
May be be associated with aura, nausea and photosensitivity
Aggravated by, or causes avoidance of, routine activities of daily living. Patients often describe ‘going to bed’.
In women may be associated with menstruation`
Describe tension headache
Recurrent, non-disabling, bilateral headache, often described as a ‘tight-band’
Not aggravated by routine activities of daily living
Describe cluster headache
-How often does this occur?
-How long does it last?
-What is this assoc with?
-Who is this more common in?
Pain typical occurs once or twice a day, each episode lasting 15 mins - 2 hours with clusters typically lasting 4-12 weeks
Intense pain around one eye (recurrent attacks ‘always’ affect same side)
Patient is restless during an attack
Accompanied by redness, lacrimation, lid swelling
More common in men and smokers
Who does cluster headache more commonly affect?
Cluster headaches are more common in men (3:1) and smokers. Alcohol may trigger an attack and there also appears to be a relation to nocturnal sleep.
Give 6 features of cluster headaches
Features
-intense sharp, stabbing pain around one eye
pain typical occurs once or twice a day, each episode lasting 15 mins - 2 hours
the patient is restless and agitated during an attack due to the severity
clusters typically last 4-12 weeks
accompanied by redness, lacrimation, lid swelling
nasal stuffiness
miosis and ptosis in a minority
Describe the headache in temporal arteritis?
Typically patient > 60 years old
Usually rapid onset (e.g. < 1 month) of unilateral headache
Jaw claudication (65%)
Tender, palpable temporal artery
Raised ESR
Medication overuse headache:
-How often is this present?
-What are suspect medications?
Present for 15 days or more per month
Developed or worsened whilst taking regular symptomatic medication
Patients using opioids and triptans are at most risk
May be psychiatric co-morbidity
What is the treatment for medication overuse headache?
Management (from 2008 SIGN guidelines)
simple analgesics and triptans should be withdrawn abruptly (may initially worsen headaches)
opioid analgesics should be gradually withdrawn
Give 3 red flag cause for headache (14)
-compromised immunity, caused, for example, by HIV or immunosuppressive drugs
-age under 20 years and a history of malignancy
-a history of malignancy known to metastasis to the brain
-vomiting without other obvious cause
-worsening headache with fever
-sudden-onset headache reaching maximum intensity within 5 minutes - ‘thunderclap’
-new-onset neurological deficit
-new-onset cognitive dysfunction
-change in personality
-impaired level of consciousness
-recent (typically within the past 3 months) head trauma
headache triggered by cough, valsalva (trying to breathe out with nose and mouth blocked), sneeze or exercise
-orthostatic headache (headache that changes with posture)
-symptoms suggestive of giant cell arteritis or acute narrow-angle glaucoma
-a substantial change in the characteristics of their headache
Give diagnostic criteria for migraine
A At least 5 attacks fulfilling criteria B-D
B Headache attacks lasting 4-72 hours* (untreated or unsuccessfully treated)
C Headache has at least two of the following characteristics:
1. unilateral location
in children, attacks may be shorter-lasting, headache is more commonly bilateral, and gastrointestinal disturbance is more prominent.
2. pulsating quality (i.e., varying with the heartbeat)
3. moderate or severe pain intensity
4. aggravation by or causing avoidance of routine physical activity (e.g., walking or climbing stairs)
D During headache at least one of the following:
1. nausea and/or vomiting*
2. photophobia and phonophobia
E Not attributed to another disorder (history and examination do not suggest a secondary headache disorder or, if they do, it is ruled out by appropriate investigations or headache attacks do not occur for the first time in close temporal relation to the other disorder)
Give the acute treatment of migraine
Acute treatment
first-line: offer combination therapy with
an oral triptan and an NSAID, or
an oral triptan and paracetamol
for young people aged 12-17 years consider a nasal triptan in preference to an oral triptan
if the above measures are not effective or not tolerated offer a non-oral preparation of metoclopramide or prochlorperazine and consider adding a non-oral NSAID or triptan
caution should be exercised when prescribing metoclopramide to young patients as acute dystonic reactions may develop
When should prophylaxis be offered for migraine?
prophylaxis should generally be given if ‘Migraine attacks are having a significant impact on quality of life and daily function, for example they occur frequently (more than once a week on average) or are prolonged and severe despite optimal acute treatment’
What can be used for migraine prophylaxis 1st line?
NICE CKS advise one of the following:
propranolol
topiramate: should be avoided in women of childbearing age as it may be teratogenic and it can reduce the effectiveness of hormonal contraceptives
amitriptyline
What can be used if 1st line prophylactic treatment for migraine is ineffective?
if measures fail NICE recommends ‘a course of up to 10 sessions of acupuncture over 5-8 weeks’
NICE recommend: ‘Advise people with migraine that riboflavin (400 mg once a day) may be effective in reducing migraine frequency and intensity for some people’
for women with predictable menstrual migraine treatment NICE recommend either frovatriptan (2.5 mg twice a day) or zolmitriptan (2.5 mg twice or three times a day) as a type of ‘mini-prophylaxis’
pizotifen is no longer recommended. Adverse effects such as weight gain & drowsiness are common
What are 2 specialist options for migraine prophylaxis?
treatment options that may be considered by specialists, but fall outside the NICE guidelines:
candesartan: recommended by the British Association for the Study of Headache guidelines
monoclonal antibodies directed against the calcitonin gene-related peptide (CGRP) receptor: examples include erenumab
What can be given for migraine in pregnancy?
Migraine during pregnancy
paracetamol 1g is first-line
NSAIDs can be used second-line in the first and second trimester
avoid aspirin and opioids such as codeine during pregnancy
What treatment can be used for migraine and menstruation?
Migraine and menstruation
many women find that the frequency and severity of migraines increase around the time of menstruation
SIGN recommends that women are treated with mefanamic acid or a combination of aspirin, paracetamol and caffeine. Triptans are also recommended in the acute situation
IS it safe to prescribe HRT with migraine?
Migraine and hormone replacement therapy (HRT)
safe to prescribe HRT for patients with a history of migraine but it may make migraines worse
What are triptans?
Triptans are specific 5-HT1B and 5-HT1D agonists used in the acute treatment of migraine. They are generally used first-line in combination therapy with an NSAID or paracetamol.
When should triptans be taken?
Prescribing points
should be taken as soon as possible after the onset of headache, rather than at onset of aura oral, orodispersible, nasal spray and subcutaneous injections are available
What are the adverse effects and contraindications of triptans?
Adverse effects
'triptan sensations' - tingling, heat, tightness (e.g. throat and chest), heaviness, pressure
Contraindications
patients with a history of, or significant risk factors for, ischaemic heart disease or cerebrovascular disease
Trigeminal neuralgia
-Describe the pain
-What is the pain evoked by
The International Headache Society defines trigeminal neuralgia as:
a unilateral disorder characterised by brief electric shock-like pains, abrupt in onset and termination, limited to one or more divisions of the trigeminal nerve the pain is commonly evoked by light touch, including washing, shaving, smoking, talking, and brushing the teeth (trigger factors), and frequently occurs spontaneously small areas in the nasolabial fold or chin may be particularly susceptible to the precipitation of pain (trigger areas) the pains usually remit for variable periods
Give 7 red flag signs in trigeminal neuralgia
Sensory changes
Deafness or other ear problems
History of skin or oral lesions that could spread perineurally
Pain only in the ophthalmic division of the trigeminal nerve (eye socket, forehead, and nose), or bilaterally
Optic neuritis
A family history of multiple sclerosis
Age of onset before 40 years
What is the management of trigeminal neuralgia?
Management
carbamazepine is first-line failure to respond to treatment or atypical features (e.g. < 50 years old) should prompt referral to neurology
What is paroxysmal hemicrania?
Paroxysmal hemicrania (PH) is defined by attacks of severe, unilateral headache, usually in the orbital, supraorbital or temporal region. These attacks are often associated with autonomic features, usually last less than 30 minutes and can occur multiple times a day.
How is paroxysmal hemicrainia treated?
PH sits within the group of disorders called trigeminal autonomic cephalgias which also contains cluster headache, a condition which shares many features with PH.
Importantly, PH is completely responsive to treatment with indomethacin.
What is idiopathic intracranial hypertension? what are 4 risk factors?
Idiopathic intracranial hypertension (also known as pseudotumour cerebri and formerly benign intracranial hypertension) is a condition classically seen in young, overweight females.
Risk factors
obesity
female sex
pregnancy
drugs
combined oral contraceptive pill
steroids
tetracyclines
retinoids (isotretinoin, tretinoin) / vitamin A
lithium
What are 5 features of idiopathic intracranial hypertension?
Features
headache blurred vision papilloedema (usually present) enlarged blind spot sixth nerve palsy may be present
Give 6 management options for MS
Management
weight loss
whilst diet and exercise are important, medications such as semaglitide and topiramate may be considered by specialists.
Topiramate is particularly beneficial as it also inhibits carbonic anhydrase
carbonic anhydrase inhibitors e.g. acetazolamide
topiramate is also used, and has the added benefit of causing weight loss in most patients
repeated lumbar puncture may be used as a temporary measure but is not suitable for longer-term management
surgery: optic nerve sheath decompression and fenestration may be needed to prevent damage to the optic nerve. A lumboperitoneal or ventriculoperitoneal shunt may also be performed to reduce intracranial pressure
Intracranial venous thrombosis
-What can this cause?
-what types do people present with?
Overview
can cause cerebral infarction, much lesson common than arterial causes 50% of patients have isolated sagittal sinus thromboses - the remainder have coexistent lateral sinus thromboses and cavernous sinus thromboses
What are common features of VST?
Common features
headache (may be sudden onset) nausea & vomiting reduced consciousness
What specific features may be seen in sagittal sinus thrombosis? 3
Sagittal sinus thrombosis
may present with seizures and hemiplegia parasagittal biparietal or bifrontal haemorrhagic infarctions are sometimes seen 'empty delta sign' seen on venography
What specific features may be seen in cavernous sinus thrombosis? 5
Cavernous sinus thrombosis
other causes of cavernous sinus syndrome: local infection (e.g. sinusitis), neoplasia, trauma periorbital oedema ophthalmoplegia: 6th nerve damage typically occurs before 3rd & 4th trigeminal nerve involvement may lead to hyperaesthesia of upper face and eye pain central retinal vein thrombosis
What specific features may be seen in lateral sinus thrombosis?
Lateral sinus thrombosis
6th and 7th cranial nerve palsies
HOw is MS diagnosed?
Patient’s with multiple sclerosis (MS) may present with non-specific features, for example around 75% of patients have significant lethargy.
Diagnosis can be made on the basis of two or more relapses and either objective clinical evidence of two or more lesions or objective clinical evidence of one lesion together with reasonable historical evidence of a previous relapse.
How can MS affect vision? 4
Visual
optic neuritis: common presenting feature
optic atrophy
Uhthoff’s phenomenon: worsening of vision following rise in body temperature
internuclear ophthalmoplegia
Describe the sensory features that can occur with MS?
Sensory
pins/needles numbness trigeminal neuralgia Lhermitte's syndrome: paraesthesiae in limbs on neck flexion
Describe the motor features that can occur with MS?
Motor
spastic weakness: most commonly seen in the legs
Describe the cerebellar features that can occur with MS?
Cerebellar
ataxia: more often seen during an acute relapse than as a presenting symptom tremor
How can MS affect urinary system?
urinary incontinence
How can MS affect sexual functions and intellectual functions?
sexual dysfunction
intellectual deterioration
What can be used to treat acute relapses in MS?
High-dose steroids (e.g. oral or IV methylprednisolone) may be given for 5 days to shorten the length of an acute relapse. It should be noted that steroids shorten the duration of a relapse and do not alter the degree of recovery (i.e. whether a patient returns to baseline function)
What are the indications for disease modifying drugs in MS?
A number of drugs have been shown to reduce the risk of relapse in patients with MS. Typical indications for disease-modifying drugs include:
relapsing-remitting disease + 2 relapses in past 2 years + able to walk 100m unaided secondary progressive disease + 2 relapses in past 2 years + able to walk 10m (aided or unaided)
Natalizumab in MS
-What is this?
-How does this work?
-When is this used and how?
natalizumab
a recombinant monoclonal antibody that antagonises alpha-4 beta-1-integrin found on the surface of leucocytes inhibit migration of leucocytes across the endothelium across the blood-brain barrier generally considered to have the strongest evidence base for preventing relapse of the disease-modifying and hence is often used first-line given intravenously
Ocrelizumab in MS
-What is this?
-When is this given and how?
ocrelizumab
humanized anti-CD20 monoclonal antibody like natalizumab, it is considered a high-efficacy drug that is often used first-line given intravenously
Fingolimod in MS
-What is this?
-how does this work?
-How is thie given?
fingolimod
sphingosine 1-phosphate (S1P) receptor modulator prevents lymphocytes from leaving lymph nodes oral formulations are availabl
Beta-interferon in MS
-How effective is this?
-How is this given?
beta-interferon
not considered to be as effective as alternative disease-modifying drugs given subcutaneously/intramuscularly
Glatiramer acetate
-How does this work?
-How is this given?
-Is this effective?
glatiramer acetate
immunomodulating drug - acts as an 'immune decoy' given subcutaneously along with beta-interferon considered an 'older drug' with less effectiveness compared to monoclonal antibodies and S1P) receptor modulators
What can be used for fatigue in MS?
Fatigue
once other problems (e.g. anaemia, thyroid or depression) have been excluded NICE recommend a trial of amantadine other options include mindfulness training and CBT
What can be used for spasticity in MS?
Spasticity
baclofen and gabapentin are first-line. Other options include diazepam, dantrolene and tizanidine physiotherapy is important cannabis and botox are undergoing evaluation
What can be used for bladder dysfunction in MS?
Bladder dysfunction
may take the form of urgency, incontinence, overflow etc guidelines stress the importance of getting an ultrasound first to assess bladder emptying - anticholinergics may worsen symptoms in some patients if significant residual volume → intermittent self-catheterisation if no significant residual volume → anticholinergics may improve urinary frequency
What can be used for oscillopsia in MS?
Oscillopsia (visual fields appear to oscillate)
gabapentin is first-line
Give 6 good prognostic features of MS?
Good prognosis features
female sex age: young age of onset (i.e. 20s or 30s) relapsing-remitting disease sensory symptoms only long interval between first two relapses complete recovery between relapses
Ways of remembering prognostic features
the typical patient carries a better prognosis than an atypical presentation
What is myaesthenia gravis?
Myasthenia gravis is an autoimmune disorder resulting in insufficient functioning acetylcholine receptors. Antibodies to acetylcholine receptors are seen in 85-90% of cases*. Myasthenia is more common in women (2:1)
Describe the key features of myaesthenia gravis? 4
The key feature is muscle fatigability - muscles become progressively weaker during periods of activity and slowly improve after periods of rest:
extraocular muscle weakness: diplopia proximal muscle weakness: face, neck, limb girdle ptosis dysphagia
What are 3 associations with myaesthenia gravis?
Associations
thymomas in 15% autoimmune disorders: pernicious anaemia, autoimmune thyroid disorders, rheumatoid, SLE thymic hyperplasia in 50-70%
What are 5 investigations for myaesthenia gravis?
Investigations
single fibre electromyography: high sensitivity (92-100%)
CT thorax to exclude thymoma
CK normal
antibodies to acetylcholine receptors
positive in around 85-90% of patients
n the remaining patients, about about 40% are positive for anti-muscle-specific tyrosine kinase antibodies
Tensilon test: IV edrophonium reduces muscle weakness temporarily - not commonly used any more due to the risk of cardiac arrhythmia
What are 3 management options for myaesthenia gravis?
Management
long-acting acetylcholinesterase inhibitors
pyridostigmine is first-line
immunosuppression is usually not started at diagnosis, but the majority of patients eventually require it in addition to long-acting acetylcholinesterase inhibitors:
prednisolone initially
azathioprine, cyclosporine, mycophenolate mofetil may also be used
thymectomy
What is the management of a myaesthenic crisis?
Management of myasthenic crisis
plasmapheresis intravenous immunoglobulins
What 6 drugs may exacerbate myaesthenia gravis?
The following drugs may exacerbate myasthenia:
penicillamine quinidine, procainamide beta-blockers lithium phenytoin antibiotics: gentamicin, macrolides, quinolones, tetracyclines
What is lambert eaton myaesthenic syndrome?
Lambert-Eaton myasthenic syndrome is seen in association with small cell lung cancer and to a lesser extent breast and ovarian cancer. It may also occur independently as an autoimmune disorder. Lambert-Eaton myasthenic syndrome is caused by an antibody directed against presynaptic voltage-gated calcium channel in the peripheral nervous system.
What are 4 features of lambert eaton syndrome? is ophthalmolegia and ptosis seen?
Features
repeated muscle contractions lead to increased muscle strength (in contrast to myasthenia gravis)
in reality, this is seen in only 50% of patients and following prolonged muscle use muscle strength will eventually decrease
limb-girdle weakness (affects lower limbs first)
hyporeflexia
autonomic symptoms: dry mouth, impotence, difficulty micturating
ophthalmoplegia and ptosis not commonly a feature (unlike in myasthenia gravis)
What is seen on EMG in lambert eaton syndrome?
EMG
incremental response to repetitive electrical stimulation
