NEUROLOGY Flashcards
What is a migraine?
Primary brain disorder, resulting from altered modulation of normal sensory stimuli - neuronal hyperexcitability
Causes aura for 15-30 min followed by unilateral, throbbing headache
Mechanism of migraine?
Neurogenic basis Wave of neuronal depolarisation followed by depressed activity from the occipital region across the cerebral cortex Activation of trigeminal pain neurones Cerebral oedema Dilatation of vessels
Causes/triggers of migraine?
Chocolate Hangovers Orgasms Cheese Oral contraceptives Lie-ins Alcohol Tumult Exercise
Symptoms of migraine without aura?
Photo/phonophobia
Motion sensitivity
Nausea/vomiting
Disabling pain - unilateral, throbbing
Symptoms of migraine with aura (25%)?
Visual aura - shimmering, zig zag lines, image fragmentation, possible hemaniopia
Tingling, dysphasia
Loss of motor control
Dizziness, vertigo
What is a hemiplegic migraine?
Causes hemiparesis with possible coma with the headache, rare
Treatment of migraine? (4)
NSAIDs
Triptans (5HT agonists) e.g. sumatriptan
Ergotamine as headache starts
Botulinum toxin type A last resort injections
When are triptans contraindicated?
IHD, coronary spasm, uncontrolled hypertension
Recent lithium or SSRI use
Prevention of migraine?
Remove triggers
Propanalol or amitriptyline or topiramate or CCBs 1st line
Valproate, pregabalin, gabapentin 2nd line
How do triptans work?
5HT agonists
Constrict arteries
Inhibit release of pro-inflammatory neuropeptides
What are the characteristics of a tension type headache?
Bilateral, non pulsatile headache, tight band sensation
Possible scalp muscle tenderness
No nausea or sensitivity to movement
How are tension type headaches treated?
Simple analgesics
Massage, ice packs, relaxation
Treatment of chronic tension headaches?
Tricyclic antidepressants
What is a cluster headache?
Recurrent bouts of excruciating pain lasting 30-90 minutes
Unilateral, retro-orbital
Cause of cluster headaches?
Possible superficial temporal artery smooth muscle hyperreactivity to 5HT
Hypothalamic grey matter abnormalities
Symptoms of cluster headaches? (3)
Excruciating pain around 1 eye
Watery eye, swollen, bloodshot
Rhinorrhoea
Frequency of cluster headaches?
Can occur multiple times a day, often at night
Clusters last 1-3 months and are followed by pain free periods of months before the next cluster
Treatment of cluster headache?
Oxygen for 15 min
Sumatriptan at onset
Preventative - steroid injections, verapimil, lithium, melatonin
What would cause acute single episode headache? (5)
Meningitis/encephalitis Trauma - intracranial haemorrhage Venous sinus thrombosis Sinusitis Acute glaucoma
What would cause recurrent acute attacks of headache? (3)
Migraine
Cluster headache
Trigeminal neuralgia
What would cause headache of subacute onset?
Giant cell arteritis
What causes chronic headaches?
Tension headache
Raised ICP
Medication overuse headache
Features of raised intracranial pressure?
Worse on waking, lying, bending forward or coughing
Vomiting, papilloedema present
Exclude SOL
Consider idiopathic intercranial hypertension
What is trigeminal neuralgia?
Paroxysms of intense stabbing pain in the trigeminal nerve distribution
Cause of trigeminal neuralgia?
Commonly starts in older age, hypertension main risk factor
Compression of the trigeminal nerve by intracranial vessels or a tumour, or inflammation
Symptoms of trigeminal neuralgia? (3)
Sudden attacks of knife like/electric shock pain lasting a few seconds
Unilateral
Commonly mandibular or maxillary divisions
Triggers of trigeminal neuralgia?
Washing face, shaving, eating, talking
Treatment of trigeminal neuralgia? (3)
Carbamazepine
Or lamotrigine, phenytoin, gabapentin
Surgery - microvascular decompression where vessels are separated from nerve root
What is giant cell (temporal) arteritis?
Systemic granulomatous arteritis that usually affects large and medium sized vessels
Common in elderly, associated with polymyalgia rheumatica
Symptoms of GCA? (4)
Headache
Temporal artery/scalp tenderness
Jaw claudication
Amaurosis fugax or sudden blindness in on eye
Treatment of GCA?
Start high dose prednisolone immediately to avoid irreversible vision loss
Investigations of GCA?
ESR and CRP high
Platelets and alkaline phosphatase high, Hb low
Temporal artery biopsy
What is a stroke?
Rapid onset of focal CNS signs and symptoms due to infarction or bleeding into part of the brain
Causes of stroke?
Ischaemic stroke - thrombosis of cerebral vessel, embolism
Haemorrhagic - intracerebral haemorrhage, subarachnoid haemorrhage
Risk factors for stroke? (10)
Age Male Family history Hypertension Smoking Diabetes Heart disease Peripheral vascular disease COCP Alcohol
What symptoms would more indicate a haemorrhagic stroke? (3)
Meningism
Severe headache
Coma
What symptoms would more indicate an ischaemic stroke? (4)
Carotid bruit
Atrial fibrillation
Past TIA
IHD
Mechanism of an ischaemic stroke?
Embolus or thrombus cuts off the blood supply so oxygen can’t reach the neurons, so they infarct causing symptoms dependent on site
Mechanism of a haemorrhagic stroke?
Bleed due to aneurysm or trauma or BP, accumulates and compresses surrounding tissue so loss of function but neurons still receive oxygen
Anatomical locations of stroke?
Cerebral
Lacunar
Brainstem
General symptoms of cerebral infarcts? (3)
Contralateral sensory loss or hemiplegia (initially flaccid then spastic - UMN)
Dysphasia
Homonymous hemianopia
General symptoms of brainstem infarcts? (3)
Quadriplegia
Disturbances of vision
Locked in syndrome
General symptoms of lacunar infarcts? (5)
Ataxic hemiparesis Pure motor Pure sensory Sensorimotor Dysarthria
Site of lacunar infarcts? (4)
Basal ganglia
Internal capsule
Thalamus
Pons
Immediate management of stroke?
Protect airway Do pulse, BP, ECG - careful about treating BP as may cause fall in cerebral pressure Glucose CT/MRI urgent if thrombolysis considered Thrombolysis within 4.5hrs if ischaemic Aspirin 300mg when haemorrhagic excluded
What is used for thrombolysis in non-haemorrhagic stroke?
Alteplase - tissue plasminogen activator
Contraindications for thrombolysis? (7)
Past intracranial haemorrhage Seizures Major infarct or haemorrhage Recent surgery/trauma On anticoagulants or INR >1.7 Low platelets Very high BP
Primary prevention of stroke?
Control risk factors - hypertension, DM, high lipids (statins), cardiac disease
Exercise
Quit smoking
Lifelong anticoagulation if left sided prosthetic valves, or if AF (warfarin)
Secondary prevention of stroke?
Control risk factors
Clopidogrel (antiplatelet) after a stroke if no haemorrhage
Warfarin (or NOAC) after stroke if AF - use antiplatelet until anticoagulated
Aspirin instead of warfarin if lower risk
What is carotid endarterectomy?
Surgery to remove atherosclerotic plaque causing narrowing of the carotid artery
Done when carotid Doppler ultrasound shows >70% stenosis
MDT management after a stroke? (5)
Stroke unit Feeding techniques Physiotherapy Home adaptations - occupational therapy Speech and language therapy
What is the CHA2DS2-VASc score?
Risk of stroke in patients with AF Congestive heart failure Hypertension Age >75 (2) Diabetes Stroke, TIA, VTE previously (2) Vascular disease Age >65 Sex - female
What is the HAS-BLED score?
Assess 1 year risk of major bleeding in patients with AF who are anticoagulated Hyperension Abnormal renal/liver function Stroke Bleeding Labile INR Elderly Drugs/alcohol
Give some NOACs and their disadvantage
Rivaroxaban
Apixaban
No antidote if bleed - warfarin has vitamin K
Where do the anterior cerebral arteries supply?
Medial side of the frontal/parietal lobes and anterosuperior part of the cerebrum - cerebrum, opthalmic artery
Where do the middle cerebral arteries supply?
Majority of the lateral cerebrum
Where do the posterior cerebral arteries supply?
Medial and lateral areas of the posterior cerebrum - occipital lobes, cerebellum, brainstem
What supplies Broca’s and Wernicke’s areas?
Broca - expressive speech, normally in dominant hemisphere (left hemisphere if right handed)
Wernicke - receptive speech
Middle cerebral artery
What is TACI and PACI?
Total and partial anterior circulation infarct
Total - affects areas of the brain supplies by ACA and MCA
Partial - only ACA
When are TACI and PACI diagnosed?
TACI is all 3, PACI is 2:
Unilateral weakness +/- sensory deficit of face, arm, leg
Homonymous hemianopia
Higher cerebral dysfunction - dyphasia, visuospatial
What is a homonymous hemianopia?
Loss of half the field of view on the same side in both eyes
What does proximal infarction of the anterior cerebral artery cause?
Paraplegia of lower limbs
Sensory loss
Incontinence
What does distal infarction of the anterior cerebral artery cause?
Contralateral hemiplegia and hemisensory loss with upper limb/face sparing
What does occlusion of the middle cerebral artery cause?
Contralateral hemiplegia with lower limb sparing
Contralateral hemisensory loss and hemianopia
Dysphagia if dominant hemisphere
What is a posterior circulation infarct?
Damage to cerebellum, brainstem
Features of a POCI?
CN palsy Contralateral or bilateral motor/sensory deficit Cerebellar dysfunction - nystagmus, ataxia Homonymous hemianopia (isolated)
What is locked-in syndrome caused by?
Infarction of the basilar artery
What are the 4 types of stroke in the bamford classification?
TACI
PACI
POCI
Lacunar syndrome
What is a TIA?
Sudden onset of focal CNS phenomena due to temporary occlusion of part of the cerebral circulation, usually by emboli, lasting <24hrs with no permanent damage
Cause of TIA?
Atherothromboembolism from the carotid artery
Cardioembolism post MI or in AF
Hyperviscosity - sickle cell, polycythaemia
Signs of TIA?
Mimic same arterial territory of stroke
Amaurosis fugax- transient loss of vision in one eye, like a curtain caused by retinal artery emboli
Tests in TIA?
FBC, ESR, U+E, glucose, lipids CXR ECG Carotid doppler USS CT/MRI
Treatment of TIA? (5)
Control CV risk factors - BP 140/85, statins, diabetes, stop smoking
Clopidogrel antiplatelet/aspirin
Warfarin if AF
Carotid endarterectomy
What is ABCD2 score?
Used to predict risk of stroke after TIA
Age >60 1
Blood pressure >140/90 1
Clinical - unilateral weakness 2, speech disturbance without weakness 1
Duration of symptoms - >1hr 2, 10-60 min 1
Diabetes 1
If >4 see stroke unit within 24hr
What is a subarachnoid haemorrhage?
Type of haemorrhagic stroke - spontaneous bleeding into the subarachnoid space
Causes of SAH?
Rupture of saccular aneurysms e.g. Berry
Arteriovenous malformations
Risk factors for SAH? (5)
Smoking Alcohol Hypertension Bleeding disorders Post menopausal loss of oestrogen
Common sites for Berry aneurysms?
Posterior communicating with the internal carotid
Anterior communicating with the ACA
Bifurcation of the MCA
Associated conditions with SAH?
Polycystic kidneys
Coarctation of the aorta
Ehler Danlos syndrome
Pathogenesis of SAH?
Release of blood into subarachnoid space leads to rise in ICP which may limit bleeding
Bleed sealed by clot but large risk of rebleed
Symptoms of SAH?
Sudden painful THUNDERCLAP usually occipital headache
Vomiting, collapse, seizures, coma
Signs of SAH?
Neck stiffness
Kernigs sign - meningism
Retinal, vitreous bleeds
Focal neurology
What is Kernigs sign?
Extension of knee painful when thigh flexed at hip
What is a sentinel headache?
SAH patients may have experienced earlier milder headache - warning leak from aneurysm
Tests for SAH?
CT - STAR SIGN
LP if CT negative
What does LP look like in SAH?
Bloody early on
Xanthochromic - yellow - after several hours due to breakdown of Hb
Management of SAH? (4)
Support - fluids, aim for BP >160 to maintain perfusion
Nimodipine to reduce vasospasm
Endovascular coiling - cathether/CT angiography
Intracranial stents/balloon for large aneurysms
Complications of SAH? (4)
Rebleeding
Cerebral ischaemia
Hydrocephalus
Hyponatraemia
What is the GCS?
Glasgow coma scale to assess level of consciousness
Components of the GCS?
EYE OPENING - none, to pain, to speech, spontaneous
VERBAL RESPONSE - none, incomprehensible, inappropriate, confused, oriented
MOTOR RESPONSE - none, extending, flexing, withdrawal, localising, obeying
15 = fully alert. 3= coma/death.
What is a subdural haemorrhage?
Bleeding from bridging veins between the cortex and venous sinuses - vulnerable to deceleration injury, resulting in accumulating haematoma between the dura and arachnoid
Pathogenesis of SDH?
Haematoma raises ICP
Shifts midline structures away from the side of the clot
Tentorial herniation and coning if untreated
Cause of SDH?
Trauma - particularly deceleration but can be minor/long ago trauma - up to 9 months
Can occur from dural metastases
What are the cortical bridging veins?
Veins which drain the underlying neural tissue and puncture the dura mater to enter dural sinuses
Layers of meninges?
Skull - dura mater - arachnoid mater - pia mater - brain
Risk factors for SDH? (4)
Elderly - brain atrophy makes veins vulnerable
Alcoholics
Epilepsy
Anticoagulation
Symptoms of SDH? (5)
Fluctuating level of consciousness Insidious physical/cognitive slowing Sleepiness Headache Personality change
Signs of SDH? (3)
Raised ICP
Seizures
Localising neuro symptoms late onset i.e. unequal pupils
Tests for SDH?
CT/MRI shows clot and midline shift
CRESCENT SHAPED BLOOD OVER 1 HEMISPHERE
Management of SDH?
Irrigation/evacuation - burr hole craniostomy
What is epidural haemorrhage?
Extradural bleed - between bone and dura - usually due to rupture of middle meningeal artery
Causes of EDH?
Fractured temporal or parietal bone lacerating MMA
Typically after trauma to a temple lateral to the eye
Tear in dural venous sinus
Clinical features of EDH? (5)
Deteriorating consciosness after head injury that initally had no loss of consciousness, or initial drowsiness that resolves LUCID INTERVAL hours/days Then decreased GCS from rising ICP Vomiting, fits, confusion, headache Brisk reflexes, upgoing plantar
Late features of EDH? (5)
Bilateral limb weakness Ipsilateral pupil dilation Coma Irregular breathing Death
Tests in EDH? (2)
CT BICONVEX rounded SHAPE from skull
Skull XR may show fracture
LP CONTRAINDICATED - decrease in ICP = herniation
Management of EDH? (2)
Stabilise
Clot evacuation +/- ligation of vessel
Features of frontal lobe damage? (4)
Personality change Loss of executive function Confabulation Motor problems Broca's aphasia
Features of temporal lobe damage? (5)
Vision problems Hallucinations Wernicke's aphasia Impaired memory/learning Deafness
Features of parietal lobe damage? (6)
Sensory loss Loss of proprioception Vision problems Dyslexia, dyscalcula Agnosia Spatial disorientation
Features of occipital lobe damage? (5)
Homonymous hemianopia Hallucinations Color agnosia Movement agnosia Blindness
Features of cerebellar damage?
DASHING Dysdiadochokinesis (impaired rapidly alternating movement) Dysmetria (past pointing) Ataxia Slurred speech Hypotonia Intention tremor Nystagmus Gait abnormality
What is cataplexy?
Sudden and transient episode of muscle weakness, triggered by emotions such as laughing or crying
Normally coexists with narcolepsy
What is narcolepsy?
Irresistible attacks of inappropriate sleep, possibly with hypnogogic hallucinations and sleep paralysis
What is raised ICP?
Increase in the contents of the cranium
Causes of raised ICP? (6)
Tumours Head injury Haemorrhage Infection Hydrocephalus Cerebral oedema
Signs/symptoms of raised ICP? (5)
Headache worse on coughing, leaning forward Vomiting Altered GCS - drowsy Falling pulse and rising BP Papilloedema
Investigation of raised ICP?
Bloods, CXR
CT head
LP if safe
Management of raised ICP? (5)
Stabilise - if intubated, hyperventilate Mannitol - osmotic agent Corticosteroids if oedema Neurosurgery if focal cause such as bleeding - craniotomy Treat cause
What is hydrocephalus?
Accumulation of CSF in the brain, causing raised ICP
Can be congenital or caused by infection, tumour, trauma
Drain
What is neurofibromatosis?
Genetic disorder (autosomal dominant) causing benign tumours to form on nerve tissue, Nf1 and Nf2 NF1 much more common
Diagnosis of NF1? 2 of…
>6 cafe au lait spots >2 neurofibromas Freckling of axillae or inguinal regions Optic glioma >2 lisch nodules Distinctive osseous lesion i.e. sphenoid dysplasia First degree relative with NF1
What are cafe au lait spots?
Flat, coffee coloured patches of skin seen in 1st year of life, increasing in size and number with age
What are neurofibromas?
Dermal - small gelatinous nodules, may itch
Nodular - arise from nerve trunks, firm, clearly demarcated, may cause paraesthesia
What are lisch nodules?
Brown/translucent mounds on the iris
Complications of NF1? (6)
Learning disability Nerve root compression GI bleeds Scoliosis Renal artery stenosis Malignancy - optic glioma, sarcoma
Management of NF1? (3)
MDT
Yearly cutaneous survey and BP
Can excise some troubling lesions
Diagnosis of NF2?
Bilateral vestibular Schwannoma on MRI/CT
AND
First degree relative with NF2 with
Either unilateral vestibular Schwannoma, or one of
Neurofibroma/meningioma/glioma/schwannoma
What is a Schwannoma?
Schwann cell tumour - vestibular is on vestibular nerve (=acoustic neuroma) affecting balance and hearing
Sensorineural hearing loss
Complications of NF2?
Tender Schwannomas of cranial/peripheral nerves
Meningiomas, gliomas
Management of NF2?
Hearing tests annually
MRI brain if hearing problems
Surgery for vestibular Schwannomas
Features of encephalitis?
Odd behaviour, decreased consciousness, focal neurology or seizure
Preceded by infectious prodrome, usually viral
Causes of encephalitis?
Viral - HSV, CMV, EBV, VZV
Non viral - bacterial meningitis, TB, malaria
Tests for encephalitis? (5)
Blood cultures, throat swab, MSU
CT with contrast
LP - increased protein, WCC, decreased glucose
EEG
Management of encephalitis? (3)
Aciclovir IV for 2 weeks
Supportive
Symptomatic - phenytoin for seizures
Emergency features of meningitis? (4)
Headache
Pyrexia
Neck stiffness
Altered mental state
Common causative organisms of meningitis?
Neisseria meningitidia or streptococcus pneumoniae
Early features of meningitis? (4)
Headache
Leg pains
Cold peripheries
Abnormal skin colour
Late features of meningitis? (5)
Meningism Decreased consciousness Seizures Non blanching purpuric rash Signs of sepsis
What are signs of meningism? (3)
Neck stiffness
Photophobia
Kernigs sign
Signs of sepsis?
Temp >38 or <36 Tachycardia >90 Resp rate >60 High or low WBC Presence of infection
Management of meningitis?
IM Benzylpenicillin in community
Cefotaxime IV
Rifampicin for contacts
What is Horner’s syndrome?
Triad of miosis (pupil constriction), partial ptosis (drooping upper eyelid), anhydrosis (ipsilateral loss of sweating)
Cause of Horner’s syndrome?
Interruption of facial sympathetic supply
e.g demyelination, thoracic outlet obstruction (lung tumour)
What is bulbar palsy?
Diseases of the nuclei of the cranial nerves 9-12 in the medulla
Signs of bulbar palsy?
LMN lesion of tongue and muscles of talking and swallowing Flaccid fasciculating tongue Jaw jerk normal/absent Quiet, hoarse speech Difficulty chewing, choking
Causes of bulbar palsy? (4)
MND
Guillian Barre
MG
Brainstem tumours
What is corticobulbar palsy (pseudobulbar)?
UMN lesion of the muscles of talking/swallowing
Cause of corticobulbar palsy? (3)
Bilateral lesions above the mid pons - MS, MND, stroke
Signs of corticobulbar palsy? (6)
Slow tongue movements Slow deliberate speech Increased jaw jerk Increased pharyngeal/palatal reflexes Weeping unprovoked Incongruent giggling
What is Bells palsy?
Abrupt onset of complete unilateral facial weakness - CN 7 - and other symptoms, diagnosis of exclusion
Symptoms of Bells palsy? (8)
Facial weakness Numbness/pain around ear Hypersensitivity to sound Decreased taste Sagged mouth one side, upturned the other Drooling Speech difficulty Watery eye
Tests in Bells palsy?
Bloods (viral antibodies)
MRI (SoL, stroke, MS)
Nerve conduction tests
Management of Bells palsy? (5)
Most fully recover spontaneously
Prednisolone within 72hr speeds recovery
Protect eye - dark glasses, artificial tears if drying, tape to close at night
Surgery if eye closure is long term problem
Plastic surgery if no recovery
Botulinum toxin
What is Guillain Barre syndrome?
Acute inflammatory demyelinating polyneuropathy
Most common acute polyneuropathy
Cause/mechanism of GBS? (3)
Immune mediated, post infectious
Campylobacter jejuni, CMV, EBV…
Infection causes antibodies that attack nerves
Symptoms of GBS? (5)
1-3 weeks after an infection, symmetrical ascending muscle weakness in limbs
Paralysis
Proximal muscles more affected - trunk, resp, CNs
Back pain, limb pain
Sweating, arrhythmias
Progressive phase 4 weeks then recovery
Investigations for CBS? (2)
Nerve conduction studies - slow
LP - high protein
Management of GBS? (3)
Ventilatory support if respiratory paralysis
IV immunoglobulin for 5 days
Possible plasma exchange
Prognosis of GBS?
85% recover, 10% unable to walk at 1 year, 10% overall mortality
What is Parkinsonism?
Triad of tremor, rigidity and bradykinesia
What type of tremor is common in Parkinson’s?
Pill rolling of thumb over fingers
Worse at rest
What type of rigidity is common in Parkinson’s?
Cogwheel rigidity - jerking stop-start during passive movement
Increased when asked to perform an action with the opposite limb
Leadpipe rigidity - sustained stiffness
What features of bradykinesia are common in Parkinson’s?
Slow to initiate movement
Slow, low amplitude repetitive actions i.e. blinking
Mask like expressionless face
What is the typical Parkinson’s gait?
Reduced arm swing
Shuffling steps with flexed trunk
Freezing at obstacles/doors
Causes of Parkinsonism?
Antipsychotics Parkinson's disease HIV Post flu encephalopathy Trauma
What is Parkinson’s disease?
Extrapyramidal movement disorder characterised by resting tremor, rigidity and bradykinesia
Motor symptoms of PD? (6)
Cogwheel rigidity Pill rolling tremor Postural instability Shuffling gait Reduced arm swing Difficulty initiating movement
Non motor symptoms of PD? (9)
Reduced smell Constipation Hallucinations Frequency/urgency Drooling Depression REM sleep disorder Dementia Mask like expression These can present years before motor symptoms.
Peak age of onset of Parkinsons?
65
Risk factors for Parkinsons? (4)
Age Male Pesticides Genetics if early onset NON SMOKERS
Pathology of Parkinsons?
Mitochondrial DNA dysfunction causes degeneration of dopaminergic neurons in the substantia nigra, associated with lewy bodies
Decreases striatal dopamine levels
Management of Parkinsons?
Exercise
Medications
Treat neuropsychiatric complications e.g. depression, dementia
Deep brain stimulation
Surgical ablation of overactive basal ganglia circuits
What genes are associated with early onset Parkinsons?
PARK 1-11 genes
What are Lewy bodies?
Tangles of alpha synuclein and ubiquitin
What medical therapy is used in Parkinson’s? (5)
Levodopa with dopa-decarboxylase inhibitor Dopamine agonists Anticholinergics - help tremor MAO-B inhibitors COMT inhiibtors
What is levodopa? Side effects?
Dopamine precursor, replacing lost dopamine
Dyskinesia, on/off effect, psychosis
Efficacy decreases with time and need bigger doses, with more side effects
What is levodopa given with?
Dopa-decarboxylase inhibitor prevents PERIPHERAL metabolism of levodopa into dopamine
Give some dopamine agonists, why are they used?
Ropinirole, bromocriptine
Can delay starting l-dopa and allow lower doses of it
What is apomorphine?
Strong dopamine agonist
Even out end of dose effects
What are MAO-B inhibitors?
Rasagiline
Inhibit dopamine breakdown, alternative to dopamine agonists
What are COMT inhibitors?
Entecapone
Lesson off time in end of dose effects, inhibit dopamine breakdown
What is Parkinson’s plus syndrome?
Parkinson’s disease features, with atypical features and poor response to l-dopa
What is Huntingtons disease?
Autosomal dominant progressive neurodegenerative disorder presenting in middle age
Early symptoms of Huntingtons disease? (3)
Irritability
Depression
Poor coordination
Later symptoms of Huntingtons disease? (4)
Chorea
Dementia
Fits
Death within 15 years
Pathology of Huntingtons disease?
Atrophy and neuronal loss of striatum of basal ganglia and cortex
Genetics - expansion of CAG repeat on chromosome 4
What is chorea?
Excessive irregular movements flitting from one body part to another - dance like
What is genetic anticipation?
Found in trinucleotide repeat disorders
Successive generations have earlier onset and more severe disease
Management of Huntingtons?
Genetic testing and counselling
No treatment affects progression - possible antipsychotics
Tetrabenazine for movement
Antidepressants
What is myasthenia gravis?
Autoimmune disease mediated by antibodies to nicotinic acetylcholine receptors interfering with the neuromuscular junction
Mechanism of mysasthenia gravus?
Antibodies to nicotinic acetylcholine receptors
Deplete working post-synaptic receptor sites at the neuromuscular junction
Prevents the end plate potential becoming large enough to trigger muscle contraction
Antibodies in myasthenia gravis?
ACh-R (against acetylcholine receptor?
MuSK (against muscle specific receptor kinase)
Associations of myasthenia gravis?
If under 50, commoner in women and other autoimmune diseases and thymic hyperplasia
If over 50 commoner in men and associated with thymic atrophy, RA, SLE
Presentation of myasthenia gravis? (7)
Increasing muscular fatigue
Ptosis
Diplopia
Myasthenic snarl (corners of mouth cant pull up)
Peek sign (separation of eyelids when eyes closed)
Voice fades when talking
Wasting long term
Order of muscles affected in myasthenia gravis? (6)
Extraocular Bulbar (chewing/swallowing) Face Neck Limb girdle (hips/shoulders) Trunk
Investigations of myasthenia gravis? (5)
Antibodies - Anti-AChR, MUSK
Decreased muscle response to repetitive nerve stimulation
CT thymus
Ice test - ptosis improves by >2mm after ice to shut lid
Tensilon test - give edrophonium and weakness improves if MG
Treatment of myasthenia gravis? (3)
Symptom control - anticholinesterase (pyridostigmine)
Relapses with prednisolone, possibly with azathioprine/methotrexate (immunosuppress)
Thymectomy if <50 and badly controlled disease
Why give anticholinesterases in myasthenia gravis?
Prolongs acetylcholine action by inhibiting cholinesterase
What is a myasthenic crisis?
Weakness of the respiratory muscles during a relapse, triggered by lack of medication, infection, stress
Management of a myasthenic crisis?
Ventilatory support
Give plasmapharesis/IB immunoglobulins
Treat trigger i.e. infection
