Neuro + gerries Flashcards
What are the four different types of dementia?
- Alzheimers
- Vascular
- Lewy Body
- Frontotemporal
What is the cause of Alzheimer’s disease?
Unknown cause
What is the pathophysiology of Alzheimer’s Disease?
Neurofibrillary tangles
Beta-amyloid protein plaque
Increased Cortical Scarring/ Atrophy
Low Acetylcholine Neurotransmitter
- Neurodegenerative disease - Neuronal damage w/ Decreased Ach
What are the risk factors for Alzheimer’s disease?
- Downs syndrome (APP Gene Mutation)
- ApoE4 Allele
- Older age
- 1st degree relative, FHx
What are the signs and symptoms of Alzheimer’s disease?
Progressive global cognitive impairment
- Aphasia
- Anosognosia - unaware of their own illness
- Amnesia (Short-term memory loss which is progressive and persistent)
- Apathy/ Anhedonia
- Appraxia
Behavioural changes
- Confusion/ Wandering/ Aggression
- Irritable/ Mood Swings
What are the investigations for Alzheimer’s disease?
1st) MMSE <25 (<17 is Severe)
Gold) Brain MRI = Medial Temporal Lobe Atrophy w/ Enlarged Lateral Ventricles
What medication can be given for Alzheimer’s disease?
1) Acetylcholinesterase inhibitors
- Donepezil or Rivastigmine
2nd) Glutamate receptor antagonist
- Memantine
3) NMDA receptor antagonist
- Quinidine
Heart Block? Cognitive Stimulation Therapy
What is the pathophysiology of vascular dementia?
Cerebrovascular (Grey and White Matter) damage due to effect of many small strokes/TIA’s in a Stepwise Pattern
What are the risk factors for vascular dementia?
- HTN/ Diabetes
- Age
- Hyperlipidaemia
- Atrial fibrillation
- History of Stroke/TIA
What are the symptoms of vascular dementia?
Sudden Onset
- Stepwise deterioration
- Motor disorders (UMN Signs)
Behavioural changes
- Cognitive impairment
- Depressions/labile mood
What are the investigations for vascular dementia?
1) MMSE <25
2) Carotid USS
3) CT/MRI head
What is the treatment for vascular dementia?
1) Treat risk factors
- Antiplatelets, Aspirin, Antihypertensitives
Gold) Acetylcholinesterase inhibitors
- Donepazil/ Rivastigmine
What is the pathophysiology of Parkinson’s disease?
Progressive reduction of dopamine from the substantia nigra in the basal ganglia leading to movement disorders
What are the symptoms of Parkinson’s disease?
Asymmetrical (One side worse than the other)
Parkinson’s Trap
T - Tremor (Resting/ Pill Rolling worse w/ Intention Movement)
R - Rigidity (Cogwheel/ Lead Pipe)
A - Akinesia (Bradykinesia)
P- Postural Instability
Extra Manifestations
- Stooped posture
- Reduced facial expressions
- Forward tilt
- Reduced arm swing
- Shuffling gait
- Depression
- Sleep disturbance
- Cognitive impairment and memory issues
What is Bradykinesia and what can you see?
Movements getting slower and smaller
- Handwriting getting smaller
- Shuffling gait
- Difficulty initiating movement
- Difficulty turning around
- Reduced facial movement or expressions (hypomimia)
How can you distinguish between the tremor of Parkinson’s disease and benign essential tremor?
Parkinson’s Tremor
- Asymmetrical
- 4-6 Hertz
- Worse at rest
- Improves with intention
- Other Parkinson’s features
- No change with alcohol
Benign essential tremor
- Symmetrical
- 5-8 Hertz
- Improves with rest
- Worse with intentional movement
- No other Parkinson’s features
- Improves with alcohol
What are Parkinson’s plus syndromes?
Group of neurodegenerative diseases featuring the classical features of Parkinson’s disease “TRAP”
Multiple system atrophy
- Parkinsonism w/ Atonic bladder, Postural hypertension and Cerebellar signs
Lewy Body Dementia
- Dementia patients w/ onset of Parkinsonism and hallucinations/ delusions, REM Disorder and fluctuating consciousness
Progressive supranuclear palsy
- Symmetrical parkinsonism w/ vertical gaze palsy and truncal rigidity
Corticobasal degeneration
- Parkinsonism W/ Apraxia, Aphasia, Asterognosis/ Phantom Limb
How would you diagnose Parkinson’s disease?
1) Clinical (Bradykinesia w/ 1 Cardinal Sign)
- UK Parkinson’s disease society brain bank clinical diagnostic criteria
What is the management of Parkinson’s disease?
1) Levodopa w/ Beneldopa/ Carbidopa
- Dopamine Agonist w/ Decarboxylase Inhibitor
OTHER
- COMT inhibitors (Entacapone) slows the breakdown of levodopa in the brain
- Dopamine agonists (Cabergoline/ Pergolide/ Bromocryptine) mimic dopamine in the basal ganglia and stimulate the dopamine receptors
- Monoamine Oxidase-B inhibitors (Selegiline) Inhibit Monoamine oxidase enzymes breaking down neurotransmitters
What disorder can Dopamine Agonists cause?
Impulse Control Disorder
- Hypersexuality
- Gambling
- High Risk Taking
What are some side effects of Levodopa?
Depression
Dry Mouth
Anorexia
Palpitations
Hypotension
Psychosis
Early Resistance
What is the action of Levodopa?
Acts as dopamine supplement crossing the blood brain barrier and activating dopaminergic receptors (D1) to replace the lack of by the Substantia Nigra Pars Compacta
What is benign essential tremor
Most common movement disorder associated with older age
- Fine tremor on all Voluntary muscles
- Most notable in the hands but can affect head, jaw and vocal
What are the features of a benign essential tremor?
- Fine Symmetrical tremor
- Prominent on voluntary movement
- Worse when tired, stressed or after caffeine
- Improved by alcohol
- Absent during sleep
What are the differential diagnoses of tremors?
- Parkinson’s disease
- Multiple sclerosis
- Huntington’s Chorea
- Hyperthyroidism
- Fever
- Medications (e.g. antipsychotics)
What is the management of a benign essential tremor?
No definitive treatment
- Propranolol - Non-selective beta-blockers
- Primidone - Anti-epileptic medication
What is motor-neurone disease?
Progressive degeneration of the upper and lower motor neurones
What are the different types of motor neurone disease?
Amyotrophic lateral sclerosis (ALS) - most common
Progressive bulbar palsy
Progressive muscular atrophy
Primary lateral sclerosis
What is Amyotrophic lateral sclerosis and what is the presentation?
Most common motor neurone disase
Mix of UMN/LMN Signs
UMN Lesion
- Hypertonia/ Hyperreflexia
- Babinski Positive
- No Fasciculations
- Increased Arm Flexion (Power)
- Increased Leg Extension (Power)
LMN Lesion
- Hypotonia/ Hyporeflexia
- Babinski Negative
- Fasciculations
- Loss of Power
What is progressive bulbar palsy and what is the presentation?
Second most common motor neurone disease
Bulbar describes LMN signs from the 9th, 10th and 12th cranial nerve lesions
Cranial Nerve Lesions
- Wasted fibrillating tongue/ flaccid tongue
- Dysarthria
- Dysphagia
- Regurgitation and choking on fluids
- Eye movements are unaffected
What is progressive muscular atrophy and what is the presentation?
- LMN only
- Wasting begins in the small muscles of the hand
- Fasciculations and Cramps
- Anterior horn cells affected
- Distal muscles are affected first then proximal
What is primary lateral sclerosis and what is the presentation?
- Rare type of motor neurone disease
- Progressive tetraparesis (muscular weakness affecting all four extremities)
- UMN affected only
What are the risk factors and potential causes of motor neurone disease?
Inheritance/ Family History
Smoking
Heavy Metal/ Pesticide Exposure
Old Male
SOD-1 Mutation
What are the signs of lower motor neurone disease?
LMN LESION
Hypotonia
Hyporeflexia
Babinski Negative
Fasciculations
Loss of Power
What are the signs of Upper motor neurone disease?
UMN LESION
Hypertonia
Hyperreflexia
Babinski Positive
No Fasciculations
Power
- Increased Arm Flexion
- Increased Leg Extension
How is motor neurone disease diagnosed?
1) Clinical presentation and excluding other conditions
2) EMG w/ Fibrillation Potentials
What is the management of motor neurone disease?
No definitive treatment
Riluzole
MDT/ Palliative
Non-invasive ventilation
PEG Feeding
What is Multiple Sclerosis/ pathophysiology?
Chronic Autoimmune Type 4 Hypersensitivity Demyelination in the CNS (Oligodendrocytes)
1) Inflammatory process involving the activation of immune cells (T cells) against the myelin = Lesions of demyelination disseminated in time and space
What are the risk factors of multiple sclerosis?
- Epstein–Barr virus (EBV)
- Low vitamin D
- Smoking/ Obesity
- Autoimmune/ Female
In who does Multiple sclerosis typically present in?
Women under 50
Autoimmune History
What are the signs and symptoms of multiple sclerosis?
1st) Optic Neuritis
- Optic nerve inflammation w/ dyschromotopsia and central scotoma
Other
Internuclear Opthalmoplegia
Trigeminal neuralgia
Numbness/ Paresthesia
Lhermitte’s sign (Electric shock w/ neck flex)
Uhtohff’s Phenomenon (Sx worse w/ heat)
UMN/ Cerebellar Signs (Charcot’s)
Charcot’s Triad
- Dysarthria
- Nystagmus
- Tremor
What are the different disease patterns of Multiple sclerosis?
Clinically isolated syndrome
First episode of demyelination and signs, cannot be diagnosed as the lesions are not disseminated in time and space
Relapsing-remitting - most common
Episodes of disease followed by recovery
Secondary progressive
Relapsing-remitting disease progressing to Primary
Primary progressive
Primary progressive MS is where there is a worsening of the disease and neurological symptoms from the point of diagnosis without initial relapses and remissions
How are the diagnoses made for multiple sclerosis?
Mcdonald’s Criteria
- 2 or more attacks disseminated in time and space
- Symptoms have to be progressive over a period of 1 year to diagnose primary progressive MS.
MRI Brain and Cord
- White Demyelination indicates space
- Gandolium Contrast used to deduce time
- Dawson’s Fingers
Nerve Conduction Studies = Delayed
Lumbar Puncture = Oligloclonal IgG Bands
Describe MRI Brain and Cord of Multiple Sclerosis
- White Demyelination indicates space
- Gandolium Contrast used to deduce time
- Dawson’s Fingers
What are other causes of optic neuritis?
Sarcoidosis
Systemic lupus erythematosus
Diabetes
Syphilis
Measles
Mumps
Lyme disease
What is the management of multiple sclerosis?
Acute
- Methylprednisolone oral/IV
Chronic
Interferon/Glatiramer, Natalizumab
Spasticity
Baclofen or Gabapentin
What is muscular dystrophy?
an umbrella term for genetic conditions that cause gradual weakening and wasting of muscles
What is the main muscular dystrophy to be aware of?
Duschenne muscular dystrophy
Give examples of different muscular dystrophies
Duchennes muscular dystrophy
Beckers muscular dystrophy
Myotonic dystrophy
What sign would you see in a child with Duchenne muscular dystrophy?
Gower’s sign
Child uses their hands on their legs to help them stand up due to proximal muscle weakness
What is the underlying genetic inheritance of Duchenne’s muscular dystrophy?
X-linked recessive - males more common
What is Duchenne’s Muscular dystrophy?
An X-linked (males more common) recessive mutation of the Dystrophin gene characterised by progressive muscle wasting and weakness
What is the pathophysiology of Duchenne’s muscular dystrophy?
Damage to the dystrophin gene
No dystrophin produced
- Dystrophin is used to strengthen and protect muscle fibres from injury
What is the prognosis of Duchenne’s muscular dystrophy?
–> wheelchair by 12 and death by 30
What are the signs and symptoms of Duchenne’s muscular dystrophy?
Under 3s w/ progressive proximal muscular dystrophy
with characteristic pseudohypertrophy of
the calves
Major milestones delayed
Inability to run, hop or jump
Recurrent falls
Speech delay
Fatigue - really common
Bulky Appearance
Respiratory Failure
Wheelchair Bound Children
What are the investigations for Duchenne’s muscular dystrophy?
1st) - Raised serum creatinine kinase
Gold) Genetic analysis
● Muscle biopsy w/ Dystrophin Assay
● Muscle strength test
● Gait assessment
What are the complications of Duchenne’s muscular dystrophy?
● Respiratory failure - most common cause of death
● Cardiomyopathies and heart failure
● Gastric dilation
● Learning difficulties
● Constipation, osteoporosis, hypertension
What is the management for Duchenne’s muscular dystrophy?
MDT CARE
● Specialist referral
● Immunisations - influenza and pneumococcal
● Physiotherapy
● Vitamin D and bisphosphonates for bone health
● Corticosteroids
● Mobility help - wheelchair once cannot walk
● Nutritional care
● End-of-life directive and palliative set-up
What is Becker’s muscular dystrophy?
–> Similar to Duchenne’s
–> dystrophin gene less affected/maintains some of its function
–> symptoms appear later around 8, some can walk assisted in adulthood
–> similar management to Duchenne’s
What are the typical features of myotonic dystrophy?
Progressive muscle weakness
Prolonged muscle contractions - e.g not being able to let go of someones hand after shaking
Cataracts
Cardiac arrhythmias
What is Huntington’s disease?
autosomal dominant progressive neurodegenerative disease
100% penetrance - all who carry the gene express the trait
trinucleotide repeat disorder
What is the pathophysiology of Huntington’s disease?
Associated with cell loss within the basal
ganglia and cortex
● Essentially too much dopamine
● See an increase in CAG repeats on the
Huntington gene, on chromosome 4p16.3
Who does Huntington’s disease affect the most?
Male aged 30-50
Huntington’s disease displays genetic anticipation, what is anticipation?
Where successive generations have more trinucleotide repeats in the gene which results in
–> earlier age of onset
–> increased severity of the disease
What is the presentation of Huntington’s disease?
It typically begins with cognitive, psychiatric or mood problems, followed by the development of movement disorders:
Chorea (involuntary, random, irregular and abnormal body movements)
Dystonia (abnormal muscle tone, leading to abnormal postures)
Rigidity (increased resistance to the passive movement of a joint)
Eye movement disorders
Dysarthria (speech difficulties)
Dysphagia (swallowing difficulties)
What are the investigations for Huntington’s disease?
● MRI/CT - Loss of striatal volume
● Genetic testing
● Rule out SLE, thyroid disease, Wilson’s
disease and dementia
What is the management of Huntington’s disease?
Manage Symptoms
Chorea? Benzo (Diazepam/ Valproic Acid)
Depressed? SSRI
Psychotic? Haloperidol
- Most common death is from concurrent
illness, e.g. pneumonia
- Suicide is the 2nd most common cause
What is meningitis?
–> inflammation of the meninges
–> inflammation usually due to bacterial or viral infection
What are the causes of meningitis in Neonates, children, adults and the elderly?
Neonates
- Group B strep
- E-Coli
Children
- Haemophilus influenza,
- Neisseria meningitides
- Strep pneumoniae (pneumococcus)
Adults
- Neisseria meningitides (meningococcus)
- Strep pneumonia
Elderly
- Strep pneumoniae
What type of bacteria is Neisseria meningitidis?
gram-negative diplococcus
also known as meningococcus
What is meningococcal septicaemia?
–> meningococcus (Neisseria meningitides) bacterial infection in the bloodstream.
–> Meningococcal refers to the bacteria and septicaemia refers to an infection in the bloodstream.
–> cause of the classic “non-blanching rash”. This rash indicates the infection has caused disseminated intravascular coagulopathy (DIC) and subcutaneous haemorrhages.
what is Meningococcal meningitis?
bacteria is infecting the meninges and the cerebrospinal fluid around the brain and spinal cord.
What is the presentation of meningitis?
Triad: Headache, neck stiffness, fever
Bacterial infection
- Sudden onset
- Bilateral Papilloedema
- Systemic symptoms - Intense malaise, rigours, photophobia, - - vomiting
- Reduced GCS, focal CNS signs, seizures
Viral:
- Self-limiting lasting 4-10 days
- May have headaches for months afterwards
Chronic: TB
- Vague symptoms of headache, anorexia, and vomiting. Triad is absent or late sign
Non Blanching Rash
Meningococcal Septicaemia
–> Neonates and babies can present with non-specific signs and symptoms, such as hypotonia, poor feeding, lethargy, hypothermia and a bulging fontanelle.
What are the two special tests that you can perform to look for meningitis?
Kernig’s test
Brudzinski’s test
What is Kernig’s test?
Involves lying the patient on their back, flexing one hip and knee to 90 degrees and then slowly straightening the knee whilst keeping the hip flexed at 90 degrees. This creates a slight stretch in the meninges. Where there is meningitis it will produce spinal pain or resistance to movement.
What is Brudzinski’s test?
involves lying the patient flat on their back and gently using your hands to lift their head and neck off the bed and flex their chin to their chest. A positive test is when this causes the patient to involuntarily flex their hips and knees.
What are the investigations for suspected meningitis?
1) Lumbar Puncture
Bacterial high protein, low glucose, high neutrophils
Viral normal protein, normal glucose, high lymphocytes
TB high protein, low glucose, high lymphocytes
Other
- Blood culture
- Throat swabs - bacterial and viral
What are the NICE criteria for meningitidis investigations for all children?
Under 1 month presenting with fever
1 – 3 months with fever and are unwell
Under 1 year with unexplained fever and other features of serious illness
What is the management of meningitis?
Community
Immediate IM or IV Benzylpenicillin
Penicillin Allergy? 1st = Transfer
Hospital
1st) Blood Culture and Lumbar Puncture
2nd) IV Cefotaxime or IV Ceftriaxone
- Add IV Vancomycin in recent travellers
- Add Amoxicillin in neonates and elderly
Rash? Benzylpenicillin IV (meningococcal septicaemia)
Prophylaxis: Contact in the last 7 days. A single dose of Oral Ciprofloxacin or Rifampicin (except in pregnancy).
Corticosteroids - Oral dexamethasone to reduce cerebral oedema and complications (hearing loss, neurological damage). 4 times daily for 4 days to children over 3 months.
Viral meningitis - LP can be done, usually self-limiting. Aciclovir may be used in HSV meningitis.
How does the appearance of CSF in bacterial and viral meningitis differ?
Bacterial - Cloudy
Viral - Clear
TB - Turbid
What are the potential complications of meningitis?
Hearing loss,
Seizures/epilepsy
Cognitive impairment/disability
Memory loss,
Focal neurological deficit.
What is Guillian-Barre syndrome?
–> Guillain-Barré syndrome is an “acute paralytic polyneuropathy” that affects the peripheral nervous system - demyelination.
–> It causes acute, symmetrical, ascending weakness and can also cause sensory symptoms.
–> It is usually triggered by an infection and is particularly associated with campylobacter jejuni, cytomegalovirus and Epstein-Barr virus.
What is Guillian- Barre syndrome normally triggered by?
–> It is usually triggered by an infection and is particularly associated with campylobacter jejuni, cytomegalovirus and Epstein-Barr virus
–> Commonly present post-GI infection (~6 weeks after)
What is the pathophysiology of Guillian- Barre syndrome?
Guillain-Barré is thought to occur due to a process called molecular mimicry. The B cells of the immune system create antibodies against the antigens on the pathogen that causes the preceding infection. These antibodies also match proteins on the nerve cells. They may target proteins on the myelin sheath of the motor nerve cell or the nerve axon.
What is the presentation of Guillian-Barre syndrome?
–> Symmetrical ascending weakness (starting at the feet and moving up the body) - TOE TO NOSE WEAKNESS
–> hyporeflexia (LMN sign)
–> There may be peripheral loss of sensation or neuropathic pain or paraesthesia
–> It may progress to the cranial nerves and cause facial nerve weakness
–> Involvement of the autonomic nervous system
○ Reduced sweating
○ Reduced heat tolerance
○ Paralytic ileus - intestinal obstruction w/o
blockage
○ Urinary hesitancy
What is the clinical course of Guillian-Barre syndrome?
Symptoms usually start within 4 weeks of the preceding infection. The symptoms typically start in the feet and progress upward. Symptoms peak within 2-4 weeks, then there is a recovery period that can last months to years.
How is a diagnosis of Guillian-Barre syndrome made?
–> clinical diangosis
–> Brighton criteria
–> nerve conduction studies - reduced signal through nerves
–> Lumbar puncture - Raised protein with a normal cell count and glucose
What is the management for Guillian- Barre syndrome?
–> IV immunoglobulins
–> Plasma exchange (alternative to IV IG)
–> Supportive care
–> VTE prophylaxis (pulmonary embolism is a leading cause of death) e.g LMWH
–> avoid corticosteroids as can make symptoms worse
–> good prognosis, most recover
What is encephalitis?
Infection and inflammation of the brain parenchyma. Broad term with various causative agents. Most commonly caused by viruses.
What are the causes of encephalitis?
Viral - most common
HSV
VZV, EBV, CMV, HIV, measles, mumps, arboviruses (West Nile)
Non-viral - Bacteria, fungal, parasitic
TB, Mycoplasma, Rickettsia, Bacterial meningitis (Listeria, Neisseria)
Cryptococcus, Histoplasmosis
Malaria, Toxoplasmosis, Schistosomiasis
Non-infectious -
Paraneoplastic
Post-infectious
Autoimmune
What is the pathophysiology of encephalitis?
An intracranial infection provokes an inflammatory response causing inflammation of the cortex, white matter, basal ganglia and brain stem depending on the causative organism. This results in neurological signs and systemic signs of infection. The frontal and temporal lobes are mostly affected. `
What is the presentation of encephalitis?
Classic triad - Fever, headache, altered mental status/focal neurological signs: Insidious onset, can also be abrupt
- Features of a viral infection to begin with - fever, malaise, nausea, headaches
- Behavioural change - a common early sign
- Decreased consciousness, confusion
- Focal neuro signs - cranial nerve palsies, hemiparesis, cerebellar ataxia, dysphagia, dysarthria
- Seizures
- Signs of raised ICP may lead to coma
What are the differentials of encephalitis?
Anything that causes behavioural change
DKA
Hypoglycaemia
Hepatic encephalopathy
B1 (thiamine) deficiency also called Beri-beri
Meningitis
Stroke
Drug overdose
Brain tumour
What are the investigations for encephalitis?
–> Lumbar puncture, sending cerebrospinal fluid for viral PCR testing
–> CT scan if a lumbar puncture is contraindicated
–> MRI scan after the lumbar puncture to visualise the brain in detail
–> EEG recording can be helpful in mild or ambiguous symptoms but is not always routinely required
–> Swabs of other areas can help establish the causative organism, such as throat and vesicle swabs
–> HIV testing is recommended in all patients with encephalitis
–> Contraindications to a lumbar puncture include a GCS below 9, haemodynamically unstable, active seizures or post-ictal.
What is the management for encephalitis?
–> Intravenous antiviral medications are used to treat the suspected or confirmed underlying cause:
–> Empirical Aciclovir in suspected encephalitis treats herpes simplex virus (HSV) and varicella-zoster virus (VZV)
–> Ganciclovir treats cytomegalovirus (CMV)
–> Repeat lumbar puncture is usually performed to ensure successful treatment prior to stopping antivirals
–> Other viral causes have no effective treatment and management is supportive.
–> Followup, support and rehabilitation is required after encephalitis, with help in managing the complications.
What are the complications of encephalitis?
Lasting fatigue and prolonged recovery
Change in personality or mood
Changes to memory and cognition
Learning disability
Headaches
Chronic pain
Movement disorders
Sensory disturbance
Seizures
Hormonal imbalance
What is Herpes Zoster?
Shingles
● Painful rash caused by reactivation of a nerve
infection caused by the varicella-zoster virus
What is the pathophysiology of herpes zoster?
First presents as chickenpox in childhood
● Varicella-Zoster remains dormant in the dorsal root ganglia
● Travels through peripheral sensory nerves to the
skin
● Less contagious than primary infection
What are the risk factors for herpes zoster?
–> immunocompromised
–> HIV
–> malignancy
What are the signs and symptoms of herpes zoster virus?
Red, painful rash - dermatomal distribution
○ Most commonly cervical, trigeminal,
thoracic and lumbar dermatomes
● Fluid-filled blisters
● Stabbing or burning pain
● Fever, headache, fatigue
● Itching
What are the investigations for herpes zoster?
● PCR test
● CSF analysis
● Bloods & cultures
● Often a clinical diagnosis
What is the treatment for herpes zoster virus?
Antiviral therapy
○ Acyclovir
○ Valacyclovir
○ Famciclovir
● Immunocompromised
patients should be
treated with IV acyclovir
● Analgesia
● Antipyretics
What is Malaria?
Malaria is an infectious disease caused by members of the Plasmodium family of protozoan parasites. Protozoa are single-celled organisms.
What is the most dangerous and severe member of the plasmodium family?
Plasmodium falciparum
how does malaria spread?
Through the bites of female anopheles mosquitoes
What are the different types of malaria?
Plasmodium falciparum is the most severe and dangerous form
Plasmodium vivax
Plasmodium ovale
Plasmodium malariae
Describe the life cycle of malaria
Malaria is spread by female Anopheles mosquitoes, most commonly at night time. Infected blood is sucked up by feeding mosquitoes. Malaria in the blood reproduces in the gut of the mosquito producing thousands of sporozoites (malaria spores).
When that mosquito bites another human or animal the sporozoites are injected by the mosquito. These sporozoites travel to the liver of the newly infected person. They can lie dormant as hypnozoites for several years in P. vivax and P. ovale.
They mature in the liver into merozoites which enter the blood and infect red blood cells. In red blood cells, the merozoites reproduce over 48 hours, after which the red blood cells rupture releasing loads more merozoites into the blood and causing haemolytic anaemia. This is why people infected with malaria have high fever spikes every 48 hours.
What is the presentation of malaria?
Symptoms occur from 6 months post-infection
P. vivax and P. ovale commonly present 6 months post-infection
Non-specific Symptoms
–>Fever, sweats and rigors
–> Malaise
–> Myalgia
–> Headache
–> Vomiting
Signs
–> Pallor due to the anaemia
–> Hepatosplenomegaly
–> Jaundice as bilirubin is released during the rupture of red blood cells
Severe disease in P. falciparum
–> Shortness of breath
–> Fits and hypovolaemia
–> AKI and nephrotic syndrome
How is malaria diagnosed?
–> Travel history
–> Thick and thin blood smears
A negative film can be seen
If negative, 2 more films should be sent over the next 48 hours
–> Rapid diagnostic tests
Detect parasitic antigens
–> PCR
–> FBC, LFTs, U&Es, blood gases, blood culture
–> CXR, lumbar puncture
What is the management of malaria?
Treatment
Chloroquine for non-falciparum malaria
Oral quinine sulphate for falciparum
Add IV quinine dihydrochloride for severe disease
Do not treat those with G6PD deficiency
Need specialist help
What are the complications of Plasmodium Falciparum malaria infection?
Cerebral malaria
Seizures
Reduced consciousness
Acute kidney injury
Pulmonary oedema
Disseminated intravascular coagulopathy (DIC)
Severe haemolytic anaemia
Multi-organ failure and death
Give an example of a benign and highly malignant brain tumour
Meningioma - benign
Glioblastoma - highly malignant
What is the presentation of brain tumours?
–> focal neurological symptoms as they develop, depends where the tumour is
–> often present with signs and symptoms of raised ICP
- headaches
- Altered mental state
- Visual field defects
- Seizures (particularly focal)
- Unilateral ptosis
- Third and sixth nerve palsies
- Papilloedema (on fundoscopy)
a patient that has had an unusual change in personality and behaviour where might a brain tumour be present based on the presentation?
The frontal lobe as this lobe is responsible for personality and high-level decision making
What are some potential causes of increased ICP?
Brain tumours
Intracranial haemorrhage
Idiopathic intracranial hypertension
Abscesses or infection
List some concerning features of a headache that should prompt further investigations.
Constant
Nocturnal
Worse on waking
Worse on coughing, straining or bending forward
Vomiting
What is papilloedema and what does it represent
–> Papilloedema is a swelling of the optic disc secondary to raised intracranial pressure
–> The sheath around the optic nerve is connected with the subarachnoid space.
–> CSF under high pressure can flow into the optic nerve sheath.
–> increases the pressure around the optic nerve where it connects with the back of the eye at the optic disc,
–> causing optic disc swelling.
–> This can be seen on fundoscopy examination. - retinal vessels are able to flow straight across a flat surface, whereas they will curve over a raised disc.
What are the common cancers that metastasise to the brain?
- Lung
- Breast
- Renal cell carcinoma
- Melanoma
What are gliomas?
Gliomas are tumours of the glial cells in the brain or spinal cord.
There are three types to remember (listed from most to least malignant):
Astrocytoma (glioblastoma multiforme is the most common)
Oligodendroglioma
Ependymoma
What are meningiomas?
Meningiomas are tumours growing from the cells of the meninges in the brain and spinal cord. They are usually benign, however, they take up space and this mass effect can lead to raised intracranial pressure and neurological symptoms.
Are pituitary tumours usually benign or malignant?
–> Benign
What is the problem if pituitary tumours become large enough?
They can press on the optic chiasm and cause bilateral hemianopia
What are the signs and symptoms of pituitary tumours and why might they occur?
–> Compression of optic chiasm - bilateral hemianopia
–> They have the potential to cause hormone deficiencies or to release excessive hormones which can lead to:
- Acromegaly
- Hyperprolactinaemia
- Cushing’s disease
- Thyrotoxicosis
What is the management of brain tumours?
Management options include:
Palliative care
Chemotherapy
Radiotherapy
Surgery - dependent on the grade and behaviour of the brain tumour
What is the treatment for pituitary adenomas?
Trans-sphenoidal surgery
Radiotherapy
Bromocriptine to block prolactin-secreting tumours
Somatostatin analogues (e.g. octreotide) to block growth hormone-secreting tumours
What are acoustic neuromas?
Acoustic neuromas are benign tumours of the Schwann cells surrounding the auditory nerve (vestibulocochlear nerve) that innervates the inner ear.
Where do acoustic neuromas normally form?
cerebellopontine angle
Are acoustic neuromas normally bilateral or unilateral?
Unilateral
What are bilateral acoustic neuromas associated with?
Neurofibromatosis type 2 - a genetic condition that causes tumours to grow along your nerves
What is the presentation of acoustic neuromas?
The typical patient is aged 40-60 years presenting with a gradual onset of:
Unilateral sensorineural hearing loss (often the first symptom)
Unilateral tinnitus
Dizziness or imbalance
A sensation of fullness in the ear
Can be a presentation of facial nerve palsy
What are the investigations for acoustic neuromas?
–> Audiometry is used to assess hearing loss. There will be a sensorineural pattern of hearing loss.
–> CT/MRI - establish the diagnosis and features of the tumour. MRI provides more detail than CT.
What is the management of acoustic neuromas?
ENT specialist management options include:
–> Conservative management with monitoring may be used if there are no symptoms or treatment is inappropriate
–> Surgery to remove the tumour (partial or total removal)
–> Radiotherapy to reduce the growth
What are the risks associated with acoustic neuroma treatment?
–> Vestibulocochlear nerve injury, with permanent hearing loss or dizziness
–> Facial nerve injury, with facial weakness
What is bulbar palsy?
Bulbar palsy refers to a set of signs and symptoms linked to the impaired function of the lower cranial nerves, typically caused by damage to their lower motor neurons or to the lower cranial nerve itself. The impacted cranial nerves are a set of nerves that arise straight from the brainstem and include cranial nerves IX (9), X (10), XI (11), and XII (12).
Lower motor neurons are the neurons that connect the central nervous system, such as the brain and spinal cord, to the muscles they innervate
What is the difference between progressive and non-progressive bulbar palsy?
–> Progressive bulbar palsy is more common and refers to the escalation of symptoms over time. It can occur in both children and adults. –> Non-progressive bulbar palsy, on the other hand, refers to bulbar palsy that does not worsen; it is considered very uncommon
What is the difference between bulbar palsy and pseudobulbar palsy?
–> share many of the same symptoms,
–> Pseudobulbar palsy (damage to the upper motor neurons) is often characterized by the atypical expression of emotion displayed by unusual outbursts of laughing or crying, called emotional lability.
–> Bulbar palsy, an individual’s emotions usually remain unaffected.
–> Pseudobulbar palsy includes the absence of facial emotions, a spastic and pointed tongue, and an exaggerated jaw jerk.
Which cranial nerves are affected in bulbar palsy?
9, 10, 11 and 12
What are the signs and symptoms of bulbar palsy?
–> Cranial nerve IX (the glossopharyngeal nerve) is involved in salivation, swallowing, and the gag reflex.
–> If cranial nerve IX is injured, it can lead to difficulty swallowing (dysphagia) and a reduced gag reflex.
–> Common signs and symptoms of damage to the other cranial nerves include difficulty chewing, nasal regurgitation, slurred speech, difficulty in handling secretions, aspiration of secretions, altered vocal ability (dysphonia) and difficulty articulating words (dysarthria), reduced gag reflex, drooling, difficulty chewing, difficulty with consonants, atrophic tongue, weak jaw/facial muscles, normal or absent jaw jerk reflex
What are the possible causes of bulbar palsy?
The most common causes of bulbar palsy include brainstem strokes and tumours. The brainstem is part of the brain where the cranial nerves arise from and where all motor control signals are transmitted. Thus, damage to the brainstem—from strokes or tumours—can damage various cranial nerves and disrupt motor control.
Other causes of bulbar palsy include certain degenerative diseases (e.g. amyotrophic lateral sclerosis), autoimmune diseases (e.g. Guillain–Barré syndrome), and genetic diseases (e.g. Kennedy disease). Amyotrophic lateral sclerosis, commonly referred to as ALS, is a rare neurological disorder characterized by the gradual deterioration and death of motor neurons. Guillain–Barré syndrome causes the immune system to attack its own nerves, potentially targeting cranial nerves. Kennedy disease is a lower motor neuron disease that can affect transmission signals between the brain and the spinal cord, potentially resulting in bulbar palsy
What are the investigations for bulbar palsy?
–> Clinical diagnosis based on history
–> CSF analysis to rule out MS
–> MRI to diagnose a brainstem stroke or tumour
What is the treatment for bulbar palsy?
–> No known treatment
–> Supportive treatment - medications to stop drooling, feeding tube to help with dysphagia, speech and language therapy to help with speech, chewing and swallowing
–> Other specific treatments based on the cause
What is the cerebellum responsible for?
The cerebellum is the region of the brain responsible for controlling stance, gait, and balance, as well as the coordination of complex and goal-directed movements
What are the causes of cerebellar syndrome?
Acute
–> Infarction, TIA
–> Head trauma, oedema, haemorrhage
–> Infections (acute postviral cerebellitis), including:
Adults: VZV, EBV, Lyme disease, tertiary syphilis, malaria, prion diseases (e.g., Creutzfeldt-Jakob disease)
Children: VZV, coxsackievirus, parvovirus B19, HHV-6, hepatitis A, enteroviruses, measles, mumps, Lyme disease, etc.
–> Medication, toxins, and poisons: barbiturates, benzodiazepines, heavy metals, and chemotherapy
Subacute and chronic
–> Alcoholism
–> Intracranial tumours (e.g., medulloblastoma)
–> Vitamin deficiencies: vitamin B12 deficiency, vitamin B1 deficiency (Wernicke encephalopathy)
–> Paraneoplastic cerebellar degeneration
–> Genetic: Friedreich ataxia, ataxia telangiectasia, spinocerebellar ataxia,
–> Multiple sclerosis
–> Wilson disease (rare)
What is the presentation of cerebellar syndrome?
DANISH
- Dysdiadochokinesis - Inability to perform rapidly alternating agonistic-antagonistic movements
- Ataxia - coordination balance and speech - gait
- Nystagmus
- Intention tremor - finger-to-nose test with shaky hands
- Scanning speech, dysarthria - words are broken down into separate syllables and spoken with varying force
- Hypotonia, hyporeflexia
cerebellar drift - pronator drift
What are the investigations for cerebellar syndrome?
Neuroimaging (CT/MRI): indicated to rule out infarction, haemorrhage, tumours, oedema
Laboratory testing: complete blood cell count; electrolytes, vitamin B12 levels, vitamin B1 levels
Genetic testing: if other diagnostic tests are negative or inconclusive
What is the management of the cerebellar disorder?
treat the underlying cause
What is Bell’s palsy?
Lower motor neuron weakness of cranial nerve VII (facial nerve) → acute peripheral facial palsy
What is the facial nerve pathway and what are the five branches?
–> exits the brainstem at cerebellopontine angle
–> passes through the temporal bone and parotid gland
–> then divides into five branches
Temporal
Zygomatic
Buccal
Marginal mandibular
Cervical
What are the three functions of the facial nerve?
motor - It supplies the muscles of facial expression, the stapedius in the inner ear and the posterior digastric, stylohyoid and platysma muscles in the neck
Sensory - It carries taste from the anterior 2/3 of the tongue.
parasympathetic - It provides the parasympathetic supply to the:
Submandibular and sublingual salivary glands
Lacrimal gland (stimulating tear production)
how can you distinguish between upper and lower motor neurone bell’s palsy?
–> Each side of the forehead has upper motor neurone innervation by both sides of the brain. However, each side of the forehead only has lower motor neurone innervation from one side of the brain
–> In an upper motor neurone lesion, the forehead will be spared, and the patient can move their forehead on the affected side. - should be referring for suspected stroke.
–> In a lower motor neurone lesion, the forehead will NOT be spared, and the patient cannot move their forehead on the affected side.
Which conditions can cause unilateral upper motor neurone facial palsy signs?
Cerebrovascular accidents (strokes)
Tumours
Which conditions can cause biilateral upper motor neurone facial palsy signs?
Pseudobulbar palsies
Motor neurone disease
What are the causes of Bell’s palsy?
idiopathic
Thought to be related to inflammation and oedema of the facial nerve secondary to viral infection or autoimmunity
What is the presentation of Bell’s palsy?
symptoms
Presents with rapid onset (<72 Hours) of unilateral facial weakness
post-auricular/ear pain
Difficulty chewing
incomplete eye closure
drooling
tingling in cheek/mouth
hyperacusis - decrease in everyday sound tolerance
Non-forehead sparing
symptoms
ocular dryness
decreased taste
Asymmetrical smile
Drooping of the corner of the mouth
Drooping of the eyebrow
What are the investigations for Bell’s palsy?
Clinical diagnosis - based on unilateral facial weakness, of rapid onset, without forehead sparing (with forehead sparing suspected UMN lesion)
→ may include routine blood tests, neuroimaging, specialist tests e.g lumbar puncture
→ consider HIV test
What is the management of Bell’s palsy?
Treatment
→ Management largely supportive, but prednisolone may be used in those presenting within 72 hours of onset. antiviral treatment e.g acyclovir can be considered
→ eye care - lubricating drops, taping eye when sleeping, sunglasses outdoors, referral to ophthalmology considered
What is epilepsy?
Epilepsy is an umbrella term for a condition where there is a recurrent tendency to have seizures - chronic
What are seizures?
Seizures are transient episodes of abnormal electrical activity in the brain. There are many different types of seizures. spontaneous and intermittent
What is ictus?
The epileptic attack itself
What is prodrome in epilepsy?
Nonspecific symptoms that precede an epileptic attack
What is aura in epilepsy?
Sensory disturbances that precede an attack, usually by minutes. More specific.
What are the potential causes/risk factors of epilepsy?
Family history – Idiopathic
Premature birth
Developmental abnormalities
Trauma
Drugs – cocaine
Space occupying lesion – tumour, infection, haematoma
What are the two main types of seizures?
–> Primary generalised - 30/40%
–> partial/focal - 60-70%
What are primary generalised seizures and what presentation are they associated with?
- Originates in the midbrain or brainstem
- Electrical discharge in both hemispheres
- Associated with LOC or awareness
What are focal/partial seizures?
–> Focal onset, an electrical discharge is restricted to one area of the brain
–> It may develop into a generalised (secondary)
Name the different types of generalised seizures
–> Generalised tonic-clonic seizures
–> tonic seizures
–> clonic seizures
–> Absence seizures
–> atonic seizures
–> myoclonic seizures
What are generalised tonic-clonic seizures (grand-mal)?
–> Often no aura
–> tonic phase - rigid, tongue biting, incontinence, no breathing during the phase
–> Clonic phase - convulsions, limb jerking, eye-rolling, uncoordinated breathing
–> self - limiting
–> Physical injuries are common
–> prolonged post-ictal phase - confused, drowsy, irritable
What are tonic seizures?
–> high tone
–> Rigid stiff limbs
–> no limb jerking
What are clonic seizures?
–> seizures with muscle jerking
what are absence seizures?
–> patient becomes blank, stares into space and then abruptly returns to normal
What are atonic (akinetic) seizures?
–> sudden loss of muscle tone and movement and they fall
–> also known as drop attacks
What are myoclonic seizures?
–> Sudden brief muscle contractions
What are the different types of partial/focal seizures?
–> Simple partial seizure
–> Complex partial seizure
–> partial seizures with secondary generalisation
What is a simple partial seizure?
–> No loss of consciousness
–> No post-ictal signs
–> isolated limb jerking
–> Head turning away from the side of the seizure
–> isolated paraesthesia
–> Todd’s paralysis - temporary paralysis/weakness
What is a complex partial seizure?
–> most commonly in the temporal lobe
–> can affect awareness/memory before during or after
–> Visual/auditory hallucinations
–> lip-smacking - automatism
–> Post-ictal confusion/drowsiness is common
what are partial seizures with secondary generalisation?
–> partial seizures that spread to the lower brain areas which initiate a generalised seizure
–> usually tonic-clonic
–> 2/3rds with partial seizures develop generalised seizures
if there is a focal seizure in the temporal lobe what presentation might be seen?
Speech comprehension, memory and emotion are affected
Anxiety
Automatisms = lip-smacking
if there is a focal seizure in the frontal lobe what presentation might be seen?
Motor disturbances
Jacksonian march = up and down the motor homunculus
Postictal Todd’s palsy
if there is a focal seizure in the parietal lobe what presentation might be seen?
sensation
Occipital = vision ( visual phenomena = spots, lines, flashes)
What are the investigations for epileptic seizures?
EEG = supports the diagnosis
MRI/ CT head = exclusion of space-occupying lesions
Blood to rule out metabolic disturbances
What is the epilepsy management
- Generalised Tonic-Clonic = Sodium Valproate for Males & women unable to childbear, Lamotrigine to females of childbearing potential
- Tonic/atonic = Sodium Valproate for Males & women unable to childbear, Lamotrigine to females of childbearing potential
- Myoclonic = Sodium Valproate for Males & women unable to childbear, Levetiracetam/Topiramate to females of childbearing potential
- Absence = Sodium Valproate for Males & women unable to childbear, Ethosuximide to females of childbearing potential
- Partial (focal) = Lamotrigine/ Carbamazepine
