DPD 4 - Neuro Flashcards
A 59 y/o man presents w/ exertional chest pain. He has long standing HTN and has a normal ECG. O/E: Frank’s sign. What is the most likely diagnosis?
- Coronary artery stenosis
- Musculoskeletal
- Pericarditis
- Relapsing polychrondritis
- Vasculitis
Coronary artery stenosis
Note that this is exertional chest pain. Frank’s sign is a diagonal crease in ear lobe extending from the tragus across the lobule to the rear edge of the auricle and is assoc. w/ ischaemic heart disease. Indicative of CVD and/or diabetes.
What can be seen in a UMN lesion e.g. brain tumour, specifically regarding the tone, power + reflex?
Increased tone = spasticity - reduced central descending inhibition
Decreased power
Increased reflexes = brisk + upgoing plantars
What can be seen in a LMN lesion, specifically regarding the tone, power + reflex?
Decreased tone = flaccid
Decreased power
Decreased reflexes
An IVDU presents w/ slurred speech, dysphagia, diplopia, bilateral ptosis + has a sluggish pupillary response to light. He has descending symmetric muscle weakness + multiple skin abscesses on arms + legs. Where is the issue likely to be located anatomically?
- Brain
- Brainstem
- Spinal cord
- Nerve root
- NMJ
NMJ
Unlikely to be in the brainstem as this would mean CN 3/4/6/9/10/11 would be knocked off so he would be dead. This is likely to be a diffuse neuromusular issue due to the diplopia and dysphagia so a NMJ issue is likely. The multiple abscesses suggests that he has run out of veins and this is an example of skin popping (injecting heroin under the skin). Infected heroin results in causing abscess infected with Botulinum toxin - this inhibits ACh release hence NMJ issue
Name 5 cerebellar signs to do with coordination.
Ataxia = uncoordinated movements
Nystagmus
Dysdiadochokinesia = rapidly alternating movement
Intention tremor = dysmetria + pass pointing on the finger-nose-finger test
Speech = slurred, scanning
What can cause a cerebellar lesion? (x 5)
Remember V, 2 I's and 2 T's Vascular - Bleed Infection - TB, VZV, cerebellitis Inflammation - MS Tumour - Primary, secondary mets Toxin - alcohol, phenytoin
A pt presents w/ a hemisensory loss, where is the damage likely to be?
- Cerebral cortex
- Spinal cord
- Nerve roots
- Mononeuropathy
- Polyneuropathy
Cerebral cortex
Hemisensory loss = different between L and R side
A pt presents w/ a sensory loss around the umbilicus. Where is the damage likely to be?
- Cerebral cortex
- Spinal cord
- Nerve roots
- Mononeuropathy
- Polyneuropathy
Spinal cord - the distribution loss is at the same level i.e. difference at particular level
A pt presents w/ sensory loss in the lateral side of their outer thigh. Where is the damage likely to be?
- Cerebral cortex
- Spinal cord
- Nerve roots
- Mononeuropathy
- Polyneuropathy
Nerve roots (radiculopathy) as it is a dermatomal distribution
A pt presents w/ sensory loss of their lateral three fingers in the right hand. Where is the damage likely to be?
- Cerebral cortex
- Spinal cord
- Nerve roots
- Mononeuropathy
- Polyneuropathy
Mononeuropathy - specific area e.g. median nerve in CTS
A diabetic pt presents w/ sensory loss in their feet and fingers. Where is the damage likely to be?
- Cerebral cortex
- Spinal cord
- Nerve roots
- Mononeuropathy
- Polyneuropathy
Polyneuropathy - glove + stocking distribution e.g. diabetic neuropathy
A 55 y/o man presents w/ numbness + tingling in hands and feet. PMHx: T1DM. DHx: On basal/bolus insulin. Ix: HbA1c 50 mmol/mol; B12: 500 PG/ML (200-900); eGFR: 90. There is decreased sensation to peripheries (glove + stocking distribution). What would you prescribe? (Not essential)
- Codeine
- Duloxetine
- Hydroxocobalamin
- Paracetamol
- Pregabalin
Pregabalin for peripheral neuropathy
What are the causes of peripheral neuropathy? (x 6 broad categories)
- Infection e.g. HIV
- Inflammation/Autoimmune e.g. GB syndrome (= acute inflammatory demyelinating polyneuropathy assoc. w/ campylobacter jejuni infection); chronic inflammatory demyelinating polyneuropathy; CTD; Vasculitis
- Toxin e.g. alcohol, cisplatin, amiodarone, metronidazole etc
- Metabolic e.g. diabetes, B12 deficiency, amyloidosis, chronic kidney disease
- Hereditary e.g. hereditary sensory motor neuropathy - pes cavus due to long standing peripheral neuropathy. A prominent example of this is Charcot-Marie-Tooth disease
What Ix would you do if you suspected alcohol was the cause of peripheral neuropathy?
Hx
Raised GGT
Raised MCV
What Ix would you do if you suspected B12 deficiency was the cause of peripheral neuropathy?
FBC to look for anaemia
Increased MCV - macrocytic anaemia
Serum B12
Define amyloidosis
Deposition of abnormal protein in various organs which affects the function. These abnormal proteins have precursors.
What are the 2 types of amyloidosis?
- Amyloidosis w/ myeloma: myeloma = increased production of immunoglobulin w/ light chain. These light chains become the precursors of amyloid fibrils
2 Chronic infection/inflammation: serum amyloid A is an inflammatory protein
A 34 y/o woman presents w/ weakness in the legs + blurred vision. She has increased tone + hyperreflexia but decreased power and pinprick sensation in the legs. Fundoscopy shows an ill-defined optic disc. What is the cause of her blurred vision?
- Amaurosis fugax
- Anterior uveitis
- Papilloedema
- Papillitis
- Vitreous haemorrhage
Papillitis = optic neuritis = inflammation of head of optic nerve
This is associated w/ pain on eye movements + blurred vision + demyelination e.g. multiple sclerosis.
Papilloedema also has a blurred optic disc on fundoscopy but is due to increased ICP + is not painful
Her weak legs suggests lesions affecting the spinal root - spastic paraparesis = increased tone w/ weak legs
What would a lesion in the corticospinal tract cause?
Weakness, hyperreflexia + upgoing plantars - the descending motor pathway is in the corticospinal tract so a lesion would result in weakness. These pathways are inhibitory therefore lesion results in increased brisk reflexes + upgoing plantars
What would a lesion in the spinothalamic tract cause?
Loss of sensation to a level. The spinothalamic tract is the ascending sensory tract therefore a lesion would result in loss of sensation
Give examples of pathology of the spinal cord (x 4 main ones)
- Spinal cord compression
- Vascular e.g. defect of anterior spinal artery
- Infection e.g. Pott’s disease (TB of the spine)
- Inflammation (demyelination) e.g. transverse myelitis = inflammation of spinal cord assoc. w/ mycoplasma pneumonia
Other causes include:
- Toxic/metabolic: subacute combined demyelination of the spinal cord
- Tumour/malignancy: primary or secondary spinal metastasis/spinal cord tumour
Describe generally the presentation of multiple sclerosis
2 lesions; separated in TIME + SPACE
e.g. papillitis - optic nerve affected; spinal cord lesion - weakness
A 60 y/o man presents w/ pain + paraesthesia on anteriolateral thigh. PMHx: T2DM. DHx: Metformin. Ix: HbA1c: 60 mmol/mol; BMI: 30 kg/m^2. O/E: Decreased pinprick sensation on anterolateral thigh. What is the most appropriate next step in his management?
- Lose weight
- Insulin
- Statin
- Aspirin
- MRI brain
Lose weight
First, you need to identify where the issue is. The dermatomal distribution suggests it is in the nerve roots (radiculopathy) so MRI brain is not needed because lesion is not in the brain. This dermatomal loss can be explained by meralgia paraesthetica
What is the definition and management of meralgia paraesthetica?
Compression of lateral femoral cutaneous nerve (L2, L3)
Tx: Reassure, avoid tight garments, lose weight. If persistent, carbamazepine, gabapentin
Which nerve supplies the sensory innervation to the lateral 3 fingers (thumb, index finger and middle finger)?
Median nerve
Which nerve supplies the pinky finger and half of 4th finger?
Ulnar nerve
Which nerve supplies the back of the thumb?
Radial nerve
What is the definition of radiculopathy?
Disease of nerve roots
What are the causes of radiculopathy?
Compression by:
- Disc herniation
- Spinal canal stenosis (degenerative changes) e.g. lumbosacral radiculopathy
What is sciatica?
Pain in buttock, radiating down to leg below the knee
A 60 y/o man presents w/ recurrent falls, tremor at rest, rigidity and is becoming more forgetful. He has dysphagia, micrographia + a limited upgaze. What is the most likely Dx?
- Progressive supranuclear palsy
- Lewy body dementia
- Stroke
- Epilepsy
- Alzheimer’s disease
Progressive supranuclear palsy = Parkinson’s + limited upgaze
Lewy body dementia will give you vivid hallucinations
What is the test for bradykinesia?
Flex fingers 2-5 to touch thumb and repeat. Bradykinesia has small magnitudes of movement
What is the classic triad of symptoms of Parkinson’s disease?
Tremor - pill rolling (at rest, unilateral)
Rigidity - increased tone, cogwheel rigidity due to increased tone and tremor)
Bradykinesia
Parkinson’s is loss of DA neurones in substantia nigra
What are the main features of progressive supranuclear palsy?
Progressive supranuclear palsy = Steele-Richardson syndrome = degenerative disease involving gradual deterioration of specific volumes of brain
Parkinsonian features + upgaze abnormality
What are the main features of Lewy Body dementia?
Features of Alzheimer’s disease
Parkinson’s
Hallucinations e.g. little gnomes running around
A 55 y/o man presents w/ confusion + chest pain. There is no headache or neck stiffness and he recently moved to a new house. O/E: Temp: 37.0; PR 110; BP 120/60; Normal CVS, Resp, GI, neuro. Ix: ECG: sinus tachycardia, widespread ST depression. Urinalysis: normal. Glucose 7.0 mmol/L. WCC: 7; CRP < 5; CT NAD. What is the most likely cause of his confusion?
- Vascular
- Infection
- Inflammation
- Toxic/metabolic
- Tumour
Toxic/metabolic
This could be a vascular cause e.g. haemorrhagic stroke but CT is NAD thus less likely. There are no features of headache, neck stiffness, fever or tachycardia thus infection + inflammation not likely. Tumour is not likely as well as CT is NAD. He recently moved to a new house so this could be CO poisoning
What are other causes of confusion or decreased AMTS? (x 4 broad causes)
- Post-ictal - Hx of seizure, requires collateral Hx
- Dysphasia (receptive/expressive) - other features of stroke /TIA N.B. this is not true confusion, simply difficulty with language
- Dementia
- Depressive pseudodementia - elderly, poor eye contact, precipitating factor
What are the 4 broad causes of dementia?
- Vascular (multi-infarct) - Hx of IHD/PVD
- Alcoholic
- Alzheimer’s disease
- Inherited e.g. Huntington’s disease - chorea is a feature of HD
What are the DDx of confusion?
Again, remember H, 2 I’s + 2 T’s
Hypoglycaemia
Vascular - Bleed, subdural haematoma (fall + fluctuating consciousness)
Infection
Inflammation - cerebral vasculitis
Malignancy
Metabolic/Toxic - endocrinopathies (Cushing’s disease may appear psychotic), vitamin deficiencies
What is the GCS?
Glasgow coma score to assess conscious level. Minimum - 3; maximum - 15
Eyes (4) - spontaneously open, opens to command, opens to pain, not open
Verbal (5) -Talking, confused, words, sounds, nothing
Motor (6) - obeys commands, localises pain, withdraws from painful stimuli, abnormal flexion, abnormal extension, nothing
What is the AMTS?
DOB, Age, Time, Year Place Recall address (given at beginning) Recognise Doctor/nurse - name and grade given at the beginning Prime minister Second WW Cound backwards from 20 to 1
A pt presents w/ headache, fever, neck stiffness. There is pain ellicited when the knee is straghtened. What is the most likely Dx + what is the name of the sign ellicited?
Meningitis
Kernig’s sign = pain when leg raised + knee straightened
A pt presents w/ sudden onset headache, worst headache ever ‘thunderclap’. What is the most likely diagnosis?
SAH
Assoc. w/ polycystic kidney disease
What Ix would you do for SAH?
CT to exclude raised ICP
LP - xanthochromia seen - breakdown of Hb
A 55 y/p pt presents w/ jaw claudication, scalp tenderness and has shoulder stiffness and pain. They have felt tired and have a fever. What is the most likely diagnosis?
Giant cell arteritis
It is assoc. w/ polymyalgia rheumatica and is a medical emergency due to risk of blindness
What Ix would you do for GCA?
ESR - raised
Temporal artery biopsy - this is diagnostic IX
What is the Tx for GCA?
Urgent high-dose prednisolone to reduce risk of blindness
A pt presents w/ a unilateral, throbbing headache around the left eye. They vomited this morning and has photophobia and phonophobia. They complain of seeing flashing lights just before the headache comes on. What is the most likely Dx?
Migraine
Strong FHx; flashing lights indicate an aura - can be negative i.e. black hole or positive i.e. flashing lights
What is the Tx of stroke < 4.5 hours onset?
- CT head to exclude haemorrhage
2. Thrombolysis (if no contraindication)
What is the Tx of stroke > 4.5 hours onset?
- CT head - if no haemorrhage then 300mg Aspirin
- Swallow assessment
- Maintain hydration, oxygenation + glucose
What is the Tx of TIA?
- Aspirin
Dont treat BP acutely unless > 220/120 or other indication
Risk factor modification e.g. aspirin, statin
What are the Ix of TIA?
ECG
Echocardiogram
Carotid doppler
You want to find cause of TIA
A 40 y/o pt presents w/ backache, LMN weakness + is admitted to HDU. Regular FVC monitoring + cardiac monitor. DHx: IVIG. What is the most likely diagnosis?
- Guillain-Barre
- Stroke
- Cord compression
- Cauda equina syndrome
- Myasthenia gravis
Guillain-Barre
FVC using a spirometer must be monitored to check for respiratory muscle weakness. If decreasing FVC - ventilate.
GBS is assoc. w/ autonomic neuropathy
Tx: IV Immunoglobulin G (IVIG)
What are the causes + respective Ix of collapse?
Hypoglycaemia - check CBG Vasovagal Outflow obstruction - aortic stenosis O/E Arrhythmia - ECG, 24hr tape Postural hypotension - lying/standing BP Seizure - Hx: before, during, after
