Neurology Flashcards
What is frontotemporal dementia
- progressive dementia
- atrophy of frontal and temporal lobes
- loss of neurons but no plaque formation
- 50% dominant inheritance
Presentation of frontotemporal dementia
often tends to be insidious and progressive
- behavioural issues
- progressive aphasia
- semantic dementia
Picks bodies
Investigations for frontotemporal dementia
- bloods
- FBC and LFTS for encephalopathy
- MMSE
- MRI
Treatment for frontotemporal dementia
- no cure
- supportive therapy
- SSRIs → behaviour symptoms
- levodopa/carbidopa if Parkinson’s symptoms
- stop exacerbating drugs
What is vascular dementia?
result of multiple, small infarcts
Risk factors for vascular dementia
- smoking
- history of TIAs
- AF
- HTN
- T1DM
- hyperlipidaemia
- obesity
- coronary heart disease
one stroke doubles risk of vascular dementia
Presentation of vascular dementia
- stepwise progression → periods of stable symptoms then sudden increase in severity
- visual disturbances
- UMN signs
- attention deficit
- depression
- incontinence
if infarct was subcortical → dysarthria, pakinsonisms
Investigations for vascular dementia
- full history → previous stroke/TIA
- cognitive impairment screen
- medication review
- MRI → previous infarcts
Treatment for vascular dementia
- supportive therapy
- SSRIs/anti-psychotics to control symptoms
- prognosis 3-5yrs
What is dementia with Lewy Bodies?
- characterised by Lewy bodies in brainstem and neocortex
- substantia nigra depigmentation and amyloid deposits
- on a spectrum
Presentation of dementia with Lewy Bodies
- initial presentation = dementia
- Parkinsonisms
- visual hallucinations
- sleepless disorders/restless leg syndrome
Diagnosis of dementia with Lewy Bodies
presence of dementia with 2 of:
- fluctuating attention/concentration
- recurrent visual hallucinations
- spontaneous Parkinsonism
- SPECT/PET scan → low dopamine transporter uptake in basal ganglia
- MMSE
- bloods
- MSU → urine infection
Treatment for dementia with Lewy Bodies
- supportive therapy
- cholinesterase inhibitors for cognitive decline
- avoid neuroleptic drugs
What is carpal tunnel syndrome?
- compression of median nerve in carpal tunnel
- median nerve → sensation to thumb/index/middle/half of ring finger
- causes unknown
Presentation of carpal tunnel syndrome
- pins and needles
- pain in index/middle finger → reaches shoulder
- numbness
- weakness, loss of grip
- worse a night
Diagnosis of carpal tunnel syndrome
- based on symptoms
- nerve conduction test
- US/MRI
Treatment of carpal tunnel syndrome
- pregnancy cases resolve postpartum
- rest wrist
- splint
- steroid injections
- surgery if severe
What is foot drop?
- difficulty lifting front part of foot → toes drag
- permanent/temporary
- damage to common peroneal/fibular nerve
Causes of foot drop
- injury
- lower back damage
- tumour
- cauda equina syndrome
- MS
Presentation of foot drop
- unilateral symptoms
- one foot drags across floor
- tripping
- numbness/weakness
Diagnosis of foot drop
- clinical diagnosis
- find cause using xray/US/CT/MRI/nerve conduction studies
Treatment of foot drop
- brace/splint
- physiotherapy
- special shoes
- nerve stimulation
- surgery
Causes of spinal cord compression
- trauma
- tumours → common spinal metastases = breast, prostate, lung
- central disc protrusion
- prolapsed disk
- infection
- epidural haematoma
Signs and symptoms of spinal cord compression
red flag signs
- loss of bladder/bowel function
- UMN signs in lower limbs eg clonus
- LMN signs in upper limbs eg atrophy
symptoms depend on injury type and site
- paraplegia
- pain
- paraesthesia
Diagnosis of spinal cord compression
- xray whole spine
- MRI if indicated
- renal function
- Hb → monitor blood loss
Treatment of spinal cord compression
- acute = emergency
- dexamethasone until treatment confirmed
- catheterisation
- analgesi
- surgical decompression
- chemo
What is the cauda equina?
formed by nerve roots caudal to spinal cord termination
What is cauda equina syndrome?
sudden severe compression of cauda equina
Causes of cauda equina syndrome
- herniation of lumbar
- tumours
- trauma
- infection
- late stage ankylosing spondylitis
- post op haematoma
- sarcoidosis
Presentation of cauda equina syndrome
- sudden onset → hrs
- saddle paraesthesia
- bladder/bowel dysfunction
- sexual dysfunction
- motor problems
- lower back pain
- bilateral LMN weakness, absent ankle reflex
Diagnosis of cauda equina syndrome
- medical emergency
- rectal exam → loss of anal tone/sensation
- MRI spine
Treatment of cauda equina syndrome
- surgical decompression
- immobilise spine
- anti-inflammatory agents
- Abs if infection
- chemo
What is Wernicke’s encephalopathy?
depletion of thiamine → vitB1
Causes of Wernicke’s
- chronic alcoholism
- severe starvation
- prolonged vomiting
Presentation of Wernicke’s
classic triad
- confusion
- ataxia
- ophthalmoplegia
- asterixis = liver flap → general sign of metabolic encephalopathy
- diagnosis = clinical
Management of Wernicke’s
- pabrinex → IV b-vitamins incl thiamine
- complication = Korsakoff’s syndrome
What is Korsakoff’s sybdrome?
- irreversible
- long term brain damage due to B1 deficiency
- decreased ability to acquire new memorites
- retrogade amnesia
- confabulation
Primary brain tumours
- less common
gliomas
- astrocytoma
- oligondendroglioma
others
- ependymoma
- meningioma
- schwannoma
- craniopharyngiomas
Secondary brain tumours
- much more common
originate from
- non-small cell lung cancer
- small cell lung cancer
- breast
- melanoma
- renal cell carcinoma
- GI
What is encephalitis?
- inflammation of brain parenchyma due to viral infection
- other causes = TB, lume disease, toxoplasmosis
Viruses that cause encephalitis
- most common = HSV1
- CMV
- EBV
Presentation of encephalitis
- fever
- headache
- altered mental status
- can present with signs of meningitis
- confusion/drowsiness
- symptoms of raised ICP
- if caught late, coma
Symptoms of raised ICP
- vertigo
- nausea
- headache
- photophobia
Diagnosis of encephalitis
- bloods
- CSF → viral PCR to detect virus
- CT/MRI
- blood cultures/gram stain
Treatment of encephalitis
- urgent admission
- acyclovir
- stat IV benzylpenicillin
- careful with fluids → cerebral oedema
What is Herpes Zoster?
- shingles
- painful rash caused by reactivation of nerve infection caused by varicella-zoster virus
- first presents as chickenpox as a kid
- remains dormant in dorsal root ganglia
- travels through peripheral sensory nerves to skin
Risk factors of herpes
- immunocompromised
- HIV
- malignancy
Presentation of herpes
rash
- red, painful
- dermatomal distribution → cervical, trigeminal, thoracic, lumbar
- fluid filled blisters
- stabbing/burning pain
- fever, headache, fatigue
- itching
Diagnosis of herpes
- PCR
- CSF analysis
- bloods
- diagnosis often clinical
Treatment of herpes
antiviral therapy
- acyclovir
- valacyclovir
- famiciclovir
- if immunocompromised → IV acyclovir
- analgesia
- antipyretics
