Neuro Flashcards
What is the condition that presents with headache, scalp tenderness and jaw claudication, and potential systemic symptoms? What would be seen on a biopsy (and where would this be done?)
Giant cell arteritis.
Granulomatous arteritis on a temporal artery biopsy
What condition and sign is associated with giant cell arteritis?
Polymyalgia rheumatica and amourosis fugax
What is the extra pyramidal triad that Parkinson’s presents with? what are other symptoms?
Pill rolling tremor (at rest), bradykinesia, hypertonia = triad. other symptoms: decreased arm swing in gait, stoop, depression, constipation, urinary incontinence
What is the pathophysiology of Parkinson’s?
progressive loss of dopamine secreting cells in the substantial nigra. Alteration in the basal ganglia which regulate movement (and of which dopamine is a key neurotransmitter). Loss of striatal pathways. Also accumulation of Lewy-bodies
Dx of Parkinson’s and conditions that should be excluded:
Exclude cerebellar disease and frontal temporal dementia. Clinical dx based on extra pyramidal triad. Clinical response to dopaminergic tx. MRI rules out structural pathology and CT shows atrpohy of the substantial nigra
What is the treatment for Parkinsons?
- Levodopa (dopamine precursor) with DOPA- decarboxylase inhibitor
- dopamine agonst (ropinirole)
- MAO-B inhibitors: efficacy decreases with time
What neurotransmitters are lost in Huntington’s disease, and what is maintained, and where in the brain does this occur?
ACh and GABA lost, dopamine spared. Occurs in the caudate nucles and basal ganglia
what is the aetiology of Huntingtons?
Autosomal dominant. CAG repeats due to genetic stutter; Huntingtin protein.
What is the tx of Huntingtons?
- no disease modifying treatment available.
- treat chorea: sodium valproate, benzodiazepines
What is Guillain Barre syndrome?
Demyelination and axonal degeneration. Rapid progressive ascending neuropathy
What is the presentation of Guillain Barre syndrome and associated syndrome?
- progressive ascending limb weakness (usually symmetrical)
- Peaks at 4 weeks
- decreased reflexes
- parasthesia
- no muscle wasting
Miller Fischer syndrome: related variant that affects cranial nerves of the eye muscles
What is the cause of gullian barre syndrome and why does it happen?
Preceding infection, usually resp or GI. Antibodies attack peripheral nerves
What are common bacteria that cause GBS?
- campylobacter jejuni
- CMV: cytomegalovirus
What is the presentation of upper motor nerve lesion?
- affects groups of muscles
- pyramidal pattern: extensors of warm and flexors of legs weakened
- spasticity, increased tone ( the faster muscles are moved, the more resistances)
- increased reflexes
- no muscle wasting
- positive Babinski sign (plantar up)
- loss of fine finger movement
- less control of active movement
- protonator drift
What is the presentation of a lower motor nerve lesion?
Patterns of weakness corresponds to the muscles supplied by the involved neurons
- flaccid weakness
- hypotonia: little resistance to passive stretch
- decreased reflexes
- muscle paralysis
- fasciculation (involuntary twitching)
- absent Babinski reflex
What are acute causes of peripheral neuropathy?
Guillan barre, nerve entrapment/trauma/lesion
What are chronic causes of peripheral neuropathy?
Diabetes, alcohol
What is amitriptyline commonly used for?
Nerve pain
What is trigeminal neuralgia and how does it present?
Knife like pain in the trigeminal/sensory division. Severe, short lasting electric shock like pain, normally unilateral. Usually a trigger
What is the given duration of a migraine?
4-72 hours
What are the classifications of headaches (and 2 examples of each(
primary (migraine, cluster) secondary (meningitis, SA haemorrhage), tension type
What are the red flags for headaches?
SNOOP10:
- S: systemic disturbance
- N: neurological symptoms/signs
- O: onset (sudden)
- O: onset age (>50 years)
- P: phenotype
- P: pattern change
- P: pregnancy
- P: papilloedema
- P: pathology existing
- P: painful eye
- P: precipitation (coughing, straining)
- P: posture
- P: past trauma
- P: painkiller useage
What is a cluster headache
Unilateral, very severe. Usually last 15mins to 3 hours. Cranial autonomic features (watery eyes/runny nose)
What is the pathophysiology of Alzheimer’s?
Accumulation of beta amyloid plaque, a degradation product of amyloid precursor protein. Results in progressive neuronal damage, neurofibrillary tangles, increased number of amyloid plauqes, loss of ACh. Neuronal loss: amygdala, hippocampus, subcortical nuclei.
What is the tx for Alzheimers?
ACh-esterase inhibitors. BP control
What are the subtypes of dementia?
- Alzheimers
- Vascular dementia (if hx of strokes/TIAs, or evidence of atheropathy)
- Lewy body dementia: fluctuating cognitive impairment, detailed hallucinations, later Parkinsons
- Fronto-temporal dementia: mixed dementia. Frontal and temporal atrophy with loss of neurons
What scan is done for dementia dx?
MRI
What is the presentation of a lesion in CN I:
decreased ability to smell
What is the presentation of a lesion in CN II
blindness, visual field defect
What is the presentation of a lesion in CN III
dilated pupil, ptosis (eye drooping)
What is the presentation of a lesion in CN IV
diplopia (double vision)
What is the presentation of a lesion in CN V:
Sensory deficit. Decreased facial sensation
What is the presentation of a lesion in CN VI
Inability of eye to look laterally (Eye to nose)
What is the presentation of a lesion in CN VII
LMN: total facial weakness
UMN: forehead sparing weakness
What is the presentation of a lesion in CN VIII
deafness
What is the presentation of a lesion in CN IX
impaired gag reflex
What is the presentation of a lesion in CN X
impaired gag reflex. Soft palate to good side when ‘aah’
What is the presentation of a lesion in CN XI
weakness turning head to affected side. Can’t shrug
What is the presentation of a lesion in CN XII
Tongue deviates to affected side
What is affected first in a nerve root lesion?
sensory then motor
What is Cauda Equina synrome, and where does the pathology occur?
Compression of the spinal cord at the level of cauda equina. Cord ends at L2 level
What is the classic presn of Cauda equina
- saddle anaesthesia
- lower back pain, bilateral sciatic
- bowel and/or bladder dysfunction
- sexual dysfunction
What ion is affected in Eaton Lambert syndrome and what is the effect?
- calcium ion channel blocked
- affects ACh release
- leads to muscle weakness
What condition has the following symptoms?proximal muscle weakness, strength that increases with more effort. Diminshed/absent reflexes. Rapid progression, dysarthria
Eaton Lambert syndrome
What is the treatment for Eaton Lambert syndrome?
Block K+ channels in post synaptic channel. Increases AP duration, as it doesn’t repolarise. Thus, calcium channels open longer, more ACh release
What is myasthenia gravis?
AID, attack ACh receptors (post synaptic). Autoantibodies to nicotinic ACh receptors or MuSK (muscle specific tyrosine kinase), on the post synaptic membrane.
What are the symptoms of myasthenia gravis?
Weakness, fatiguability of occular (ptosis: eyelids droop), bulbar weakness (dysphagia, dysarthria), proximal limb weakness that improves after rest
What condition is myasthenia gravis associated with?
Thymic hyperplasia. In 10% cases, a thymic tumour can be found (thymoma).
What is the dx of myasthenia gravis?
- anti ACHr antibodies in serum
- nerve stimulation test (characteristic decrement of evoked action potential following motor nerve stimulation)
- Ice test: improvement of ptosis with ice pack
- Cogan’s eye twitch: sign elicited by instructing patient to look down for 15 seconds, gaze upwards and return to normal
What is the treatment of myasthenia gravis?
Pyridostigmine: acetylchinesterase inhibitor
What is the colloquial name of shingles and what virus causes it?
- Herpes Zoster
- Varicellar Zoster virus reaction: herpes virus 3
Describe chicken pox rash and systemic symptoms
fever, malaise, headache, abdominal pain. Rash, then scabbed over vesciles
Describe the events in shingles:
- pre eruptive: no skin lesions, but burning and itching on one dermatome
- eruptive: skin lesions appear. erythmatous, swollen plaques, doesn’t cross deratomes
How does shingles develop
Chicken pox primary infection via respiratory droplets, invades the lymph nodes, infects skin epithelial cells. LEads to virus containing vesicles (chicken pox). Remainns dormant in sensory nerve roots. Reactivated= shingles
What is shingles treatment?
oral aciclovir
What are the majority of brain tumours?
Gliomas or meningioma
Where are common primary sites for brain mets?
Bronchus, breast, kidney, thyroid, stomach, pancreas
Presentation of meningitis vs encephalitis
The hallmark signs of meningitis include some or all of the following: sudden fever, severe headache, nausea or vomiting, double vision, drowsiness, sensitivity to bright light, and a stiff neck. Encephalitis can be characterized by fever, seizures, change in behavior, and confusion and disorientation.
What is encephalitis?
inflammation of brain parenchyma
What are common causes of encephalitis?
often presumed viral, but never identified. Herpes simplex virus, coxsackie. mumps. Tick norne. HIV, MMR
What is typically seen in a lumbar puncture for encephalitis?
increased protein and lymphocytes, decreased glucose
What is the clinical presentation of acute bacterial meningitis?
Headache, neck stiffness, fever, photophobia, vomiting. Kernig’s sign. Papilloedema. Progressive drowsiness
What is Kernig’s sign?
Severe stiffness of the hamstrings causes an inability to straighten the leg when the hip is flexed to 90 degrees.
What is a specific symptom of meningococcal septicaemia?
purpuric, non blanching rash
What is the differences between viral and bacterial meningitis?
Viral has all the same presentation but is usually more self limiting and benign. Also, no rash
What is the LP is bacterial meningitis?
Polymorphs seens, cloudy apperance, increased protein and glucose
What is the LP if viral meningits?
lymphocytes seen, clear. Increased protein. Decrease glucose
What is the empirical tx for meningitis?
- empirical cefotaxime (can penetrate BBB, works on gram neg and positive)
What reduces the long term effects of menginitis?
dexamethasone