Clinical Neurology Flashcards
Describe the clinical spectrum of pathological MND.
- UMN disease
- PLS [primary lateral sclerosis]
- PBP [progressive bulbar palsy]
- ALS [amyotrophic lateral sclerosis]
- PMA [progressive muscular atrophy]
- LMN disease
Describe the clinical features seen in MND.
- more UMN: increased tone, hyperreflexia, extensor-plantar response, spastic gait, exaggerated jaw jerk, slowed movement
- ‘neutral’ symptoms: speech, swallow, speaking symptoms
- more LMN: wasting, weakness, fasciculations, reduced/absent reflexes
Describe the investigations and management regarding MND [4].
- El Escorial criteria
- neuroimaging and lab studies are required to exclude other disease; MND is a diagnosis of exclusion
- ‘general’ Mx: speech therapy, ‘voice banking’, dietician support, gastrostomy, respiratory care, riluzole (only licenced Dx)
- symptomatic management for sialorrhoea, muscle cramp, muscle spasm, respiratory, dyspnoea and anxiety
Describe tremor and the conditions in which it may occur [5].
- rhythmic sinusoidal oscillation of a body part
- essential tremor: most common postural tremor when hand is outstretched; slow progression, but may be disabling
- Wilson’s disease
- asterixis (hepatic encephalopathy)
- titubation (oscillations of the head)
Describe dystonia [3].
- sustained or intermittent muscle contractions causing abnormal, often repetitive, postures / movements or both
- typically patterned, twisting, and tremulous
- often initiated by a voluntary action; may be improved by a sensory tic
Define chorea and ballism [2], and name the main causes [5].
- chorea: brief, purposeless movements that flit and flow from one body part to another; patients often appear restless or fidgety
- ballism: extreme variant of chorea, involving proximal joints and resulting in large amplitude flinging movements, often in a hemi-body distribution
- causes: BG lesions, Sydenham chorea, Huntington chorea, APLS, neuroacanthocytosis
Describe myoclonus and negative myoclonus.
- brief, electric-shock like jerks, caused by brief activation of a muscle group, leading to a jerk of an affected body joint
- negative myoclonus: produced by temporary cessation of muscle activity (e.g., liver flap)
Describe tics.
- repetitive, stereotyped movements / vocalisations; these are initially suppressable
- anxiety and discomfort leading up to tics causes a buildup and flurry of tics when allowed to relax
- motor tics include blinks, head jerks, arm/leg jerks, complex sequence jerks
- Gilles de la Tourette’s syndrome: persistent, multiple motor and vocal tics, often associated with psychiatric disturbance
[1/3] Describe the epidemiology (risk factors, genes, protective factors) and pathology of Alzheimer’s disease.
- risks: male, pesticides, prior head injury, rural living (well-water drinking), beta blockers, agriculture
- genes: GBA, LRRK2, PARKIN, SCNA
- protective: tobacco, coffee, NSAIDs, CCBs, alcohol
- pathology: degeneration of the substantia nigra and loss of the dark pigment in the SN locus coeruleus. Lewy bodies are present, which contain alpha-synuclein
[2/3] Describe the motor and non-motor presentations of Alzheimer disease [3 + 4].
- motor: TRAP (tremor, rigidity, akinesia, posture)
- tremor: pill-rolling
- rigidity: cog-wheel and lead pipe. rigidity felt throughout movement. Froment’s test is +ve
- akinesia: slow alternating repetitive movements
- posture: stooped, slow turning, small shuffling steps
- non-motor (psych): dementia, depression, psychosis, REM sleep behaviour
- non-motor (other): constipation, GI motility, orthostatic hypotension, sialorrhoea
[3/3] Describe the diagnosis and management options for Alzheimer’s; this includes symptomatic management [4 + 3].
- clinical diagnosis: akinesia + one of the other symptoms (TRAP)
- diagnostic testing is not normally needed; brain imaging (+ SPECT) can show reduction of the substantia nigra from a ‘comma’ to a ‘full stop’.
- dopaminergic Tx (L-DOPA, MAOB inhibitors, COMT inhibitors, amantadine) should be initiated when symptoms are disabling / uncomfortable
- symptomatic treatments:
- dementia: AChI, rivastigmine
- depression, psychosis (SSRIs, TCAs, antipsychotics)
- sleep disturbance (BZDs, melatonin)
Describe the indications for neuroimaging, and the differences in CT and MRI.
- headache/raised ICP, seizure, weakness, stroke, trauma, LOC, neurological deficit, post-op
- CT: primary modality used. excellent bony detail and spatialities. Acquisition is not direct but instead axial
- MRI: best for soft tissue. Not compatible with pacemakers, implants, and ICU equipment
Describe the stages of MRI.
- T1 hyperdense: shows fat + 4Ms (methemoglobin - subacute haematoma), minerals (Ca, Mg), melanin (melanoma), mush (proteinous fluid)
- T1 hypointense: water, cortical bone, arteries
- T2 hyperintense: fat, water (‘T2 = H2O’), air, fluids, oedema, demyelination, gliosis, some tumours
- T2 hypointense: blood products, minerals, air, cortical bone, arteries
Describe the general principles of neuromuscular disorders, based on which part of the NMJ they affect.
- presynaptic: intially, fatigue improves with exercise. autonomic features are common. ocular muscles are rarely involved.
- postsynaptic: fatigues with exercise. autonomic features tend not to occur. ocular features (e.g., ptosis, diplopia) are common.
- muscle: myalgia, muscle weakness, wasting, hyporeflexia, myotonia etc.
Describe where in the NMJ the three main NMJ pathologies (botulism, LEMS, MG) occur, and therefore what their core clinical features are.
- LEMS -> presynaptic calcium channels (autoantibodies to, closely related to SCLC). presynaptic -> proximal weakness initially improving with exercise, autonomic features (dry eyes/mouth, orthostatic hypotension, constipation, ED, reduced reflexes)
- botulism -> presynaptic protein cleaving, blocking vesicle blocking with the presynaptic membrane. features have rapid onset, similar to LEMS
- MG -> postsynaptic ACh receptors (autoantibodies to, closely related to thymic hyperplasia). postsynaptic -> muscle features (weakness, dysphagia, larynx / jaw/ neck) weakness, ocular features (ptosis, diplopia)
Name the five main categories of muscle pathology, and give examples of each.
- immune: dermatomysitis, polymyositis
- inherited: muscular dystrophy, dystrophinopathies, limb girdle muscle dystrophy, myotonic dystrophy
- congenital: myasthenic syndromes, myopathies
- infective: coxsacchie, trypanosomiasis, borrella etc.
- rhabdomyolysis: crush injury, AKI
Describe and define cognition and dementia.
- cognition: the mental action of acquiring knowledge and understanding through thought, experience, and senses. it comprises attention, social and executive function, memory, and language
- dementia: undoing of the mind. requires evidence of significant cognitive decline, interference with independence, and the condition not to be better explained by another condition (and not occur exclusively in the setting of delirium).
Describe the main acute [5] causes of dementia.
- viral encephalitis of the temporal lobe (focal injury)
- head injury of the frontal lobe (focal injury)
- stroke (focal injury - presentation depends on area involved)
- transient global amnesia: anterograde > retrograde memory loss (difficulty ‘laying down’ memory) for <24h
- transient epileptic amnesia: recurrent TGA; carries out complex activities with no recollection; responds to AEDs
Describe the main subacute [4] causes of dementia.
- VINDICATE: infection (HIV, syphilis); degenerative (CJD, below); intoxication (alcohol, CO); autoimmune (limbic encephalitis, below)
- functional/subjective cognitive impairment: everyday forgetfulness which impacts on function
- Creutzfeld-Jakob disease: degenerative proteinopathy. May be sporadic, variant, iatrogenic, or genetic; all forms terminate in spongiform change in the brain
- limbic encephalitis: antibody mediated (VCKC; anti-Hu) causes short-term memory deficit
Describe the pathology of Alzheimer’s, as it relates to dementia.
- Alzheimer’s forms, solely or in part, 75% of dementias.
- neurodegenerative proteinopathy (amyloid) disrupts cholinergic pathways, causing synaptic loss, then extracellular plaques, and intracellular neurofibrillary tangles.
- degeneration of the medial hippocampus (and later, parietal lobes) causes general forgetfulness, apraxia, and visuo-spatial difficulties
- temporoparietal atrophy, decreased uptake on SPECT, and increased tau protein
- atypical presentations more associated with younger patients, including posterior cortical atrophy (visuospatial), and progressive primary aphasia (semantic, logopenic, non-fluent naming / repeating)
Name and describe the main (non-Alzheimer) causes of gradual-onset dementia, along with their management [5]. Hint: most can be summarised as dementia, plus another core clinical feature.
- frontotemporal dementia (FTD): dementia, psychiatric (disinhibition, apathy, compulsion, loss of insight). trial trazodone and anti-psychotics
- vascular dementia (VaD): dementia with cerebrovascular disease (decreased attention, slowed processing, executive factors). manage vascular factors and trial cholinesterase inhibitors
- dementia with Lewy bodies (DLB): dementia with motor features (fluctuating cognition, visual hallucinations, extrapyramidal features). Give levodopa and small-dose anticholinesterase inhibitor.
- Parkinson’s dementia: overlaps with Parkinson’s (!!)
- Huntington’s: dementia of early onset (30-50) with psychiatric symptoms (mood/personality change, chorea, psychosis)
Describe the key clinical features of CNS tumours.
- progressive neuro deficits, motor weakness, headache, seizure
- balance problems and morning headache/N&V (due to posterior fossa location)
- papilloedema
Name the four main types of nervous system tumour, and give a brief overview of their classifications.
- ASTROCYTOMA (60%)
- I. truly benign, surgery curative
- II. low grade, all will dedifferentiate if not treated
- III. anaplastic astrocytoma
- IV. glioblastoma multiforme, spreads by white matter and dismal prognosis. treated by the Stupp protocol
- OLIGODENDROCTOMA (20%). usually affects frontal lobes, and calcifies (unlike astrocytoma)
- MENINGIOMA
- classification: classic, atypical, malignant. surgery is curative
- NERVE SHEATH TUMOURS
- schwannoma, suggests NF II
- pineal gland tumours
For what is the Stupp protocol is used, and what it is comprised of? [4]
- the Stupp protocol is used for grade IV astrocytoma (glioblastoma multiforme, GBM).
- it comprises surgery, radiotherapy, and temozolmide.
- carmustine wafers may be used as chemotherapy in the brain
- inform the DVLA in all cases