Neurology (4) Flashcards
What is Frank’s sign? What is it a sign of?
Diagonal earlobe crease from tragus to rear auricle – it is a sign of diabetes mellitus and cardiovascular disease (IHD)
What are the two main questions you must consider with any neurological condition?
What is the problem?
Where is the problem?
- Brain (BS, cerebellum), SC, nerve roots, peripheral nerves, NMJ, muscle
List a surgical sieve that you can use to consider different types of causes of neurological symptoms.
Vascular Infection (subacute Hx) Inflammation/Autoimmune Toxic/Metabolic Tumour/Malignancy
Hereditary/Congenital (Pes Cavus)
NOTE: INVITED MD can also be used (infection, neoplasia, vascular, inflammatory/autoimmune, trauma, endocrine, degenerative - Parkinson’s, metabolic, drugs)
List the order in which different optic nerve functions are tested in a neurological examination.
Visual acuity (count fingers, hand movements, light perception)
Visual fields
Pupillary reflexes
Fundoscopy
Main features of upper motor neurone lesions
Hyperreflexia
Hypertonia (spasticity)
Upgoing plantars
Reduced power
Main features of lower motor neurone lesions
Hyporeflexia Hypotonia (flaccid) Wasting Reduced power Fasciculations
Where is the lesion likely to be in a patient with widespread bilateral derangement of motor function?
Neuromuscular junction
Name an important condition that causes loss of motor function in which the lesion is at the level of the neuromuscular junction.
Myasthenia gravis – autoantibodies against nicotinic acetylcholine receptors
What is Lambert-Eaton syndrome caused by?
Defect in the calcium channel on the presynaptic membrane involved in vesicular exocytosis
Similar symptoms to myasthenia gravis
What is a major risk factor for botulism?
IV drug use (expecially under the skin - skin popping –> skin abscess)
Botox inhibits ACh release so affects a wider range
Describe the test used to confirm a diagnosis of botulism.
Bioassay – two mice are injected with a serum sample from the patient, and one of the mice is given the botulinum antitoxin. If the mouse without the antitoxin dies, it is botulism
Describe the neurological signs seen in the examination of a patient with botulism.
LMN lesion signs:
Hyporeflexia
Hypotonia
Reduced power
What are the six main features of cerebellar disease?
DANISH
Dysdiadochokinesia Ataxia Nystagmus Intention tremor (Dysmetria, pass-pointing) Scanning speech (+ slurred) Hypotonia
Using the surgical sieve mentioned previously, list some causes of cerebellar disease.
Vascular – bleed in the cerebellar fossa
Infection – TB, varicella zoster, cerebellitis
Inflammation – MS
Tumour – primary or metastases
Toxic/Metabolic – alcohol, phenytoin
Describe how the anatomical level of a sensory lesion affects the area of which the abnormal sensation experienced.
Brain – hemisensory Spinal cord – at spinal cord level (e.g. T10 = umbilicus) Nerve root (radiculopathy) – dermatomal Mononeuropathy – specific area of skin Polyneuropathy – gloves and stockings
What is the most common cause of polyneuropathy?
Diabetes mellitus
What is duloxetine and what can it be used to treat?
Anti-depressant (SNRI)
It can be used to treat peripheral neuropathy and premature ejaculation
Which other drug may be used to treat neuropathic pain?
Pregabalin
List the main toxic/metabolic causes of peripheral neuropathy.
Drugs Alcohol B12 deficiency Hypothyroidism Uraemia Amyloidosis Diabetes mellitus
Suggest investigations that may reveal clues about each of the causes listed above.
Drugs – history
Alcohol – history + high GGT + high MCV
B12 deficiency – low Hb + high MCV
Hypothyroidism – TFTs
Uraemia – U&Es
Amyloidosis – history of multiple myeloma or chronic infection/inflammation
Diabetes mellitus – history + blood glucose + HbA1c
Explain why myeloma is associated with amyloidosis.
Myeloma causes increased production of immunoglobulins, which have light chains
The light chains are a precursor to amyloid fibrils
Deposition of abnormal protein in various organs
Explain why chronic inflammation/infection is associated with amyloidosis.
Inflammation leads to high levels of serum amyloid protein A (an acute phase protein)
List some associated symptoms to ask patients presenting with neurological symptoms.
Impaired vision Impaired hearing Headache Speech disturbance Weakness Sensory disturbance Bowel continence Urinary continence
List some inflammatory/autoimmune causes of peripheral neuropathy.
Vasculitis
Connective tissue diseases
Demyelinating polyneuropathy (e.g. Guillain-Barre syndrome)
Define ‘paraprotein’.
Monoclonal immunoglobulin or light chain present in the blood or urine
Describe the appearance of the feet in patients with long-term peripheral neuropathy.
High-arched foot (pes cavus)
Clawed toes
What is amaurosis fugax?
Painless temporary loss of vision in one or both eyes; descending curtain
List two causes of blurring of the optic disc margin and explain how you would differentiate between them.
Papilloedema – NO pain and NO blurring of vision
Papillitis – pain and blurring of vision
What is papillitis? What is it associated with?
Inflammation of the head of the optic nerve, associated with dymyelination (MS)
In which part of the spinal cord do you find the descending inhibitory tracts? What happens if there is a lesion?
Corticospinal tract - results in brisk reflexes and upgoing plantars. In Descending motor pathway: weakness
What happens if the spinothalamic tract is compressed at a particular level?
Impaired/loss of sensation up until the level of the lesion
Define paraparesis.
Partial paralysis of the lower limbs
Spastic paraparesis - increased tone, weak legs
State a vascular cause of spastic paraparesis.
Obstruction of the anterior or posterior spinal arteries
State an infective cause of spastic paraparesis.
TB of the spine (Pott’s disease)
State an inflammatory (demyelinating) cause of spastic paraparesis.
Transver myelitis (may be associated with infections e.g. chest infections caused by Mycoplasma pneumonia)
What features of the history are necessary for a diagnosis of multiple sclerosis?
Two lesions separated in time and space
Which condition causes pain and paraesthesia on the anterolateral thigh? (Reduced pinprick sensation)
Meralgia paraesthetica
What is this meralgia paraesthetica caused by?
Compression of the lateral femoral cutaneous nerve
Outline the treatment of this condition.
Reassure the patient that it isn’t something serious
Avoid tight garments
Lose weight
Which pharmaceutical options might you consider if the treatments persist despite these measures?
Carbamazepine
Gabapentin
Describe the sensory innervation of the hand, and signs if the nerves are affected
Front:
Ulnar – medial 1.5 fingers
Median – lateral 3.5 fingers
Back:
Ulnar – medial 1.5 fingers
Radial – rest of the back of the hand
Median – finger tips of 1st, 2nd and 3rd digits
Ulnar claw
Radial - wrist drop; check base of hand
Median: Opposition affected, thumb abduction - point to the ceiling affected
What is a radiculopathy?
Disease of the nerve roots
What is sciatica?
Pain in the buttock, radiating down the leg below the knee
It is caused by compression of the lumbosacral nerve roots
What can cause compression of nerve roots?
Disc herniation
Spinal canal stenosis (degen)
Describe the main features of Parkinson’s disease.
Rigidity Bradykinesia Resting tremor (Pill Rolling, unilateral) Gait instability (Dysphagia, amnesia, micrographia)
List some other diseases that cause symptoms that are similar to Parkinson’s disease.
Progressive supranuclear palsy (Parkinsons + limited upgaze)
Lewy body dementia
What is the key feature of progressive supranuclear palsy that helps distinguish it from Parkinson’s disease?
Limited up-gaze
What is the underlying pathological process that causes Parkinson’s disease?
Depletion of dopaminergic neurons in the subtantia nigra
What is cogwheel rigidity caused by?
A tremor superimposed on increased tone
What is another name for progressive supranuclear palsy?
Steele-Richardson syndrome
What are the key features of Lewy body dementia?
Vivid Hallucinations
Alzheimer’s
Parkinsonism
If there are no abnormalities seen on examination and imaging of a patient presenting with confusion, what is the likely cause?
Toxic/metabolic
What dangerous state can cause confusion and chest pain?
Carbon monoxide poisoning
List four causes of confusion with reduced AMTS.
Post-ictal
Dysphasia - not true confusion
Dementia
Depressive pseudodementia - withdrawn, poor eye contact, precipitating factor (death)
List 5 causes of dementia.
Alzheimer’s disease Vascular dementia Lewy body dementia Alcoholism Inherited (e.g. Huntingdon’s disease)
Given the causes of dementia listed above, what are some important features of the history that you should check?
History of ischaemic heart disease/peripheral vascular disease
History/signs of alcohol abuse
Other symptoms (e.g. Huntingdon’s chorea)
List a differential diagnosis for confusion and reduced consciousness.
Hypoglycaemia Vascular (i.e. bleed) Infection Inflammation - cerebral vasculitis (rash) Malignancy Toxic/metabolic
What are some distinguishing features of a subdural haematoma?
Falls and fluctuating consciousness
What are the main symptoms of intracranial infection?
Headache
Neck stiffness
Changed behaviour
Fever
State an inflammatory cause of confusion with reduced consciousness.
Cerebral vasculitis
List some investigations you would perform to look for a toxic/metabolic cause of confusion with reduced AMTS.
Drug history U&Es LFTs Vitamin deficiencies Endocrinopathies (Cushing's psychosis)
Which endocrine disease may present with confusion?
Cushing’s disease
What is the motor criteria of the GCS?
6 (obeys commands > localises pain > withdrawal from pain > flexion to pain (decorticate) > extension to pain (decerebate) > no motor response)
What is the verbal criteria of the GCS?
5 (oriented > confused > inappropriate words > incomprehensible sounds > no verbal response)
What is the eye criteria of the GCS?
4 (spontaneous eye opening > eye opening in response to speech > eye opening in response to pain > no eye opening)
In the AMTS, patients are asked to count backwards from 20 to 1. Why is this done?
To check for any deficits in attention/concentration
What are the four main diseases that you need to think about when a patient presents in the emergency department with a headache?
Meningitis
Giant cell arteritis
Subarachnoid haemorrhage
Migraine
List the main symptoms of meningitis.
Headache Neck stiffness Fever Photophobia Kernig’s sign
What is Kernig’s sign?
When the hip is flexed and the knee is at 90 degree, extension of the knee causes pain
Describe the presentation of subarachnoid haemorrhage.
Sudden-onset worst headache ever
What is the first investigation that is performed in suspected SAH?
CT Head
What would you look for when doing a lumbar puncture of a patient with SAH?
Xanthochromia (yellow discolouration of the CSF due to the break down of haemoglobin)
List the main symptoms of giant cell arteritis.
Headache
Loss of vision
Jaw claudication
Scalp tenderness
Which disease is giant cell arteritis associated with?
Polymyalgia rheumatica (Shoulder girdle pain, systemic upset)
How do you treat giant cell arteritis?
High-dose prednisolone - blindness risk
List two investigations that you would perform in a patient with giant cell arteritis.
ESR
Temporal artery biopsy
Describe the features of migraine.
Unilateral, throbbing pain around the eye, vomiting, photo/phono phobia, FHx
List examples of negative and positive auras.
Negative – dark, black holes
Positive – flashing lights
What is the window for thrombolysis in a patient with stroke?
Within 4.5 hours of onset of symptoms
Which investigation must you perform in stroke patients before giving any treatment?
CT Head – exclude haemorrhage
Describe the management of a stroke patient who presents > 4.5 hours after the onset of symptoms.
CT head to exclude haemorrhage
Aspirin (300 mg)
Swallow assessment
Maintain hydration, oxygenation and monitor glucose
At what point do you worry about the blood pressure of a patient with a TIA?
If the blood pressure rises > 220/120 mm Hg
Otherwise don’t treat acutely
Describe the management of a patient with TIA.
Aspirin
Risk factor modification
List some investigations that you would perform in a patient with a TIA.
ECG (AF)
Echocardiogram
Carotid artery Doppler (CA Stenosis)
Why is it important to monitor FVC in a patient with Guillain-Barre syndrome?
It can cause respiratory muscle weakness and reduce ventilation
How is FVC monitored?
Spirometry
What must you do if the FVC begins to drop?
Ventilate
Why is it important to set up a cardiac monitor for patients with Guillain-Barre syndrome?
Guillain-Barre syndrome is associated with autonomic neuropathy
How is Guillain-Barre syndrome treated?
IVIg
Construct a simple list of causes of collapse.
Hypoglycaemia
Cardiac – vasovagal, arrhythmia, outflow obstruction, postural hypotension
Neurological – seizure
Give another 2 causes of blurred vision
Anterior uveitis, vitreous haemorrhage
Other causes of spastic parasthesia
Toxic/metabolic: subacute combined demyelination of the spinal cord; tumour malig/mets
How do you test bradykinesia?
Fingers 2-5 to touch thumb
Proximal Myopathy - name 4 causes
Cushings
Thyrotoxicosis
Osteomalacia
Vit D deficiency
Name infections and inflammatory causes of peripheral neuropathy
Infection – HIV
Inflammation – Guillain-Barre syndrome, ConTis Disease, Vasculitis, CIDP (Chronia inflammatory demyelinating polyneuropathy)
Name toxic causes of peripheral neuropathy
Alcohol, cisplatin, amiodarone, metronidazole, phenytoin, isoniazid, nitrofurantoin, gold
Name Metabolic causes of peripheral neuropathy
Diabetes, amyloidosis, CKD, B12 Deficiency
Name Hereditary causes of peripheral neuropathy
Hereditary - CMT disease, Dejerine-Sottas Disease, Refsum disease
Name malignant causes of peripheral neuropathy
Paraneoplastic syndromes
Paraproteinaemia
