NEURO: Primary Brain tumours, Meningitis, Encephalitis and Zoster Hepres Flashcards
1
Q
What are primary tumours
A
Tumour growing at the anatomical site where tumour progression began + proceeded to form a cancerous mass
2
Q
What is the telencephalon
A
Cerebral hemispheres
3
Q
What is the mesencephalon
A
Midbrain
4
Q
Role of glial cells
A
Maintain homeostasis
Support and protection for neurones
Form myelin
5
Q
Name 4 glial cells
A
- Oligodendrocytes
- Astrocytes
- Ependymal cells
- Microglial
6
Q
Role of astrocytes
A
Form BBB
7
Q
Role of microglia
A
Resident macrophages of CNS
8
Q
What are glial cell carcinomas called
A
Gliomas - malignant by the time they are diagnosed
9
Q
Role of the pineal gland
A
Produces Melatonin which modulates sleep patterns
10
Q
Name 4 primary tumours of the brain
A
Anaplasia
Atypic
Neoplasia
Necrosis
11
Q
What is anaplasia
A
Loss of DIFFERENTIATED cells
Total loss of control over normal function
12
Q
How do cells become anaplastic
A
Neoplastic tumour cells dedifferentiate to become anapaestic
Cancer stem cells over multiply (uncontrolled growth due to failure of differentiation)
13
Q
What is Atypia
A
Cancer cells with structural abnormalities
14
Q
What is neoplasia
A
Uncontrolled division of cells
15
Q
How do neoplasms effect the brain
A
Grow in confined spaces increasing ICP and invading into the brain as they grow in small spaces - compression of brain structure
16
Q
Consequences of neoplastic growth
A
ICP
Destruction of brain parenchyma
17
Q
In what patients are primary brain tumours common
A
- Paediatric cancer
18
Q
What are the main types of gliomas
A
- Astrocytoma (MOST COMMON PRIMARY BRAIN TUMOUR)
2. Oligodendroglioma
19
Q
Risk factors for primary brain tumours
A
- Ionising radiation
- Vinyl Chloride
- Immunosuppreison
- Family History - Genetics
20
Q
Name Grade I astrocytoma
A
- Pilocytic astrocytoma
2. Subependymoma
21
Q
`characteristics of grade I astrocytomas
A
- Slow growing tumours where total remission is achieved by removal (stereotactic surgery)
22
Q
Characteristic of grade II astrocytomas
A
Slow growing benign to malignant tumours
Invasive gliomas that penetrate into surrounding brain (CAN’T be surgically removed)
23
Q
Name a grade II astrocytoma
A
- Fibrillary astrocytoma
24
Q
Clinical presentation of grade II astrocytoma
A
- SEIZURES
25
Name a grade III astrocytoma
Anapaestic astrocytoma
26
Characteristics of grade III astrocytomas
Astrocytes lack vascular proliferation and necrose (These are undifferentiated gliomas)
MALIGNANT
27
How are grade III astrocytomas
1. Radiotherapy
28
Name a grade IV astrocytomas
Glioblastoma multiform
29
Characteristics of grade IV astrocytomas
MALIGNANT tumours
Grow quickly and spread to other parts of the brain
So infiltrative no surgical removal of tumour impossible + RADIOTHERAPY doesn't work
Necrosis
30
Symptoms of grade IV astrocytomas
BEGIN abruptly with seizures
31
What do all gliomas progress to at end-stage cancer
Glioblastoma Multiforme (EXCEPT pilocytic astrocytoma)
32
Clinical presentation of brain gliomas
1. Headaches
2. Vomiting
3. Seizures
4. Cranial nerve disorders
5. PAPILLOEDEMA
-------INCREASED ICP symptoms------
33
Clinical presentation of spinal cord gliomas
1. Pain
2. Weakness
3. Numbness
34
How do gliomas metastasise
Spread via the CSF
35
What causes malignant gliomas
(50-60)
1. Initial genetic error in glucose glycolysis
2. Mutation of ISOTRATE DEHYDROGENASE
3. Excess build up of 2-hydroxyglutarate
This triggers instability in glial cells and oevrmitosis
OR (older)
CATASTROPHIC GENETIC MUTATION which is sporadic
36
Clinical presentation of oligodendromas
1. Seizures of the frontal lobe
2. Increased ICP symptoms
3. Visual loss, motor weakness and cognitive decline
37
What grade cancer are oligodendromas
II
38
What causes oligodendromas
IDH-1 mutation
39
In what dura layer are meningiomas made
Arachnoid mater: push into brain but are usually benign
40
What are neurofibromas
Solid benign tumours form Shwann cells
41
Where are neurofibromas found
Cerebellopontine angle
42
What are craniopharyngiomas
Brian tumour from pituitary gland embryonic tissues
43
Where are craniopharyngiomas common
Children
44
Are crnaiopharyngiomas benign or malignant
Benign
45
If Primary brian tumours are benign how can they cause damage
Act as SPACE OCCUPYING LESIONS which increase ICP
46
Why is there no symptoms when tumour is small
Initially brain removes CSF from ventricles and spinal cord to offset increase in ICP
47
How does ICP affect brian structures
Midline structure shift and herniation through foramen magnum = brain damage
48
Symptoms of ICP associated headaches
1. WORSE on waking in the morning (we don't pee at night so accumulation of fluid = ICP)
2. Pain can be so bad it can wake patient up
3. Pain increased by coughing, straining and bending forwards (increased venous pressure in brain)
4. Relieved by vomiting (reduces fluid levels)
49
Is papilloedema bilateral or unilateral
BILATERAL
50
What causes papilloedema
Increased ICP
Resp failure!
Guillain-Barre syndrome due to increased protein levels
Tumours of frontal lobe
51
What is papilloedema
Optic disc swelling
52
Clinical presentation papilloedema
1. Venous engorgement
2. Haemorrhages over optic disc
3. Blurring of optic margins
4. Enlarged blind spot on examination
53
Pathophysiology of papilloedema
Optic nerve sheath is continuous with subarachnoid space of the brain so increased ICP is transmitted through this sheath
54
how long does it take for papiloedema to present
DAYS
55
Clinical presentation of tumours affecting different parts of the brain
```
Temporal - Dysphagia, amnesia
Forntal: Hemiparesis, personality change, brook's dysphagia, lack of initiative, unable to plan tasks
Parietal lobe: Hemisensory loss, reduction in 2-point discrimination, dysphagia, astereognosis (unable to recognise object from touch alone)
Occipital: Contralateral visual defects
Cerebellum: DASHING
D - Dysdiadochokinesis
A - Ataxia
S - Slurred speech (dysarthria)
Hypotonia
Intention tremor
Nystagmus
Gait abnormality
```
56
What seizures are common with brian tumours
PARTIAL or FOCAL
57
Differential Diagnosis of primary brain tumours
1. Aneurysm
2. Abscess
3. Cyst
4. haemorrhage
5. Idiopathic intracranial hypertension
58
Diagnostic of primary brain tumours
1. EEG
2. MRI and CT (looks at disruption of BBB)
3. FBC
4. BIOPSY
59
Why does tumour of the frontal lobe cause site loss and what kind of hemianopia is this
COMPRESSION of optic chiasm
Causes bilateral temporal visual field defect
60
How do carry out a biopsy for primary brian tumours
1. BURR-HOLES
61
Why is lumbar puncture contraindicated in primary brain tumours
1. Withdrawing CSF with presence of mass lesion causes CONING
62
What is coning
Herniation of the brain through the foramen magnum resulting in BRAINSTEM COMPRESSION as it passes through foramen magnum
63
Treatment for primary brain tumours
1. ORAL DEXAMETHASONE
2. ORAL CARBAMAZZEPINE (anticonvulsant)
3. Chemotherapy
64
Why is oral dexamethasone given for primary brain tumours
1. Rapidly improves brain performance and reduces inflammation caused
65
Why is dexamethasone not given after 2:00
Keep patient awake
66
Chemotherapy for gliomas
1. TEMOZOLOMIDE
67
Where are the most common neoplasms to metastasise to CNS
1. Non small cell lung
2. Small cell lung
3. Breast
4. Melanoma
5. Renal cell
6. GI
68
How is secondary brain tumours treated
1. Surgery
2. Radiotherapy
3. Chemotherapy
4. Palliative therapy
69
What is meningitis
Acute inflammation of the meninges (dura, arachnoid and pia)
70
What causes meningitis
Streptococcus pneumoniae
Neisseria meningitidis
Haemophilus influenza
71
Clinical presentation of meningitis
1. SEVERE headache
2. Neck stiffness due to increased muscle tone)
TRIAD:
High Fever
Altered mental health
RIGIDITY
3. Photophobia
4. Photophobia
(children just look irritable and don't suffer from 3 and 4)
5. POSITIVE Kerning's sign and Brudzinski's sign
```
6. Signs of increased ICP:
Papilloedema
Headaches
Fevers
Malaise
```
7. Patient is irritable
72
How is Kerning's sign tested on a patient
1. Patient lies supine and flexes hip and kneed to 90 degrees
POSITIVE - pain limits passive extension of the knee
73
How is Brudzinski's sign tested on a patient
1. Flexion of the neck causes flexion of knee and hip
74
How can Neisseria meningitidis be differentiated from other forms of meningitis
1. Rapidly spreading petechial rash which precedes the symptoms that is NON-BLANCHING (redness does not disappear when pressed) + purpuric skin rash
75
What is a petechial rash
1. Irregular purple or red spots on trunk, lower extremities, conjunctiva and palms or soles
76
Clinical presentation of viral meningitis
1, Genital Herpes
2. Hand
3. Foot and Mouth disease
77
How is neisseria meningitidis spread
1. DROPLET SPREAD
78
What causes meningitis in pregnant women
LISTERIA MONOCYTOGENES found in cheese (why they are told to avoid) and transmitted to baby
79
Neonatal cause of meningitis
1. E.coli (found in digestive system of pregnant women)
2. Cryptococcus neoformans
3. TB
4. HIV
5. Hepres simplex virus
6. B-Haemolytic streptococcus which usually inhabit vagina
80
Risk factors of meningitis
1. Spinal canal drug administration
2. Immunocompromised (FUNGAL)
3. Elderly
4. Pregnant
5. Bacterial endocarditis
6. Crowding
7. Diabetes
8. Malignancy
9. IV drug abuse (FUNGAL)
81
Pathophysiology of staph, pseudomonas and gram-negative bacterial meningitis
1. Skull trauma allows nasal cavity bacteria to enter meningeal space (meningococcal septicaemia)
82
Clinical presentation of meningococcal septicaemia
1. Petechial rash (purpuric skin rash) + signs of sepsis
Pia-arachnoid is congested with polymorphs forming a layer of pus which organise to form adhesions causing cranial nerve palsy and hydrocephalus
83
How does TB cause meningitis
Crosses BBB and forms small subpial focus
Becomes a rich focus (large sized granuloma) and ruptures = meningitis
Viscous green-grey exudate covering brain
84
How is TB meningitis diagnosed
LUMBAR PUNCTURE
| NAAT
85
Viral causes of meningitis
1. Herpes simplex virus
2. Enteroviruses
3. Mumps
86
Fungal cause of meningitis
Cryptococcus neoformans
87
Clinical presentation of viral caused meningitis
1. NO pus formation with lymphocytic infiltration
NO cerebral oedema unless encephalitis develops
88
Complications of meningitis
1. DIC
2. Gangrene
3. Sepsis features
4. Waterhouse-Friderichsen syndrome due to bleeding of adrenal glands
5. Herniation through skull base
6. Focal seizures
7. Loss of consciousness
8. Hearing loss
9. ENCEPHALITIS
89
What is Waterhouse-Friderichsen syndrome
Haemorrhage of adrenal glands = failure due to meningococemia
Organ failure
Low BP
Shock
DIC with widespread purport seen
90
How long does viral meningitis last
4-10 days
91
What causes chronic meningitis
Mycobacterium tuberculosis
92
Differential diagnosis of meningitis
1. Aseptic meningitis (tumour)
2. Sub-arachnoid haemorrhage (headache more sudden)
3. Encephalitis
93
Diagnosis of meningitis
1. BLOOD TEST/CULTURE FIRST
2. Lumbar puncture (CSF PCR for viruses!!! - Culture for bacteria!!!)
3. Throat swabs
4. Pneumococcal serum PCR
94
CSF findings in different causes of meningitis
Bacterial (acute): Low Glucose, High protein
Acute viral: Normal glucose, Normal protein
TB (chronic): Low Glucose, High Protein
Fungal: Low Glucose, High Protein
Malignant: Low Glucose, High Protein
95
What should FBC show for meningitis
1. Hyponatreamia common due to ADH over-porudction and too much IV fluid administration
96
How do we test CSF for bacterial and listeria causes of meningitis
CULTURE it do not gram stain as it isn't specific
97
Treatment of bacterial meningitis
1. Treatment using Empiric antibiotics (Cefalosporins like cefotaxime)
Ampicillin - Listeria monocytogenes
2. Corticosticostreoids (DEXAMETHASONE) to reduce cerebral oedema
3. IV vancomycin in return travellers
98
How long should TB meningitis be treated for
A year (compared to 6 months lung TB)
99
Prophylaxis of meningitis
1. ORAL CIPROFLOXACIN stat
100
Complications of meningitis treatment
Hearing loss
Seizures
Developmental problems
101
How is meningococcal septicaemia treated
IV BENZYLPENICLLIN immediately or IV CEFOTAXIME in hospitals
102
When is lumbar puncture contraindicated
1. Mass or abscess present
2. ICP raised
3. MENINGOCOCCAL SEPSIS as it causes coning of cerebellar tonsils
103
What is encephalitis
1. Inflammation of the brain
104
Viral causes of encephalitis
HERPES SIMPLEX VIRUS
RABIES
POLIOVIRUS
MEASLES
105
How does Herpes Simplex Virus cause encephalitis
1, Transmission of virus from peripheral site on face following HSV-1 reactivation along nerve axon, to the brain
2. Virus lies dormant in GANGLION of trigeminal cranial nerve
106
Bacterial causes of encephalitis
1. Bacterial meningitis
2. Syphilis
3. TB
4. Malaria
107
Risk factors of encephalitis
1, HIV
| 2. Immunocompromised
108
What lobes of the brain are affected in encephalitis
Frontal and temporal lobes mainly but affects the whole brain
109
Clinical presentation of encephalitis
1. Consciousness decrease
TRIAD: Fevre, headache and altered mental status
2. Viral infection signs
3. Seizures
4. Raised ICP (papilloedema)
5. Focal neurological deficit (hemiparesis and dysphagia)
6. Coma
SIGNS OF MENINGITIS if caused in meaning-encephalitis
110
Differential diagnosis of Encephalitis
1. Meningitis
2. Stroke
3. Brain Tumour
111
Diagnostics of Encephalitis
1. MRI
2. EEG
3. Lumbar Puncture
4. FBC
112
Role of MRI in Encephalitis
1. Shows area of inflammation and swelling of temporal lobes in HSV encephalitis
2. May be midline shifting due to raised ICP
113
Role of EEG in encephalitis
1. Shows periodic sharp and slow wave complexes
114
Role of lumbar puncture in Encephalitis
1. CSF shows elevated lymphocyte count
2. CSF PCR for viral detection (herpes simplex virus)
3. FBC and CSF serology
115
Treatment of encephalitis
1. ANTI-VIRAL treatment - IV ACYCLOVIR before investigation
2. Anti-seizure medication (PRIMIDONE)
3. IM BENZYLPENICILIN if meningitis is suspected
BENXYLPENICILLIN is the emergency drug for meningitis
116
What is Herpes Zoster virus
1. Reactivation of varicella zoster virus - chickenpox in the dorsal root ganglia
117
What is the significance of shingles developing
1. Decline in cell-mediated immunity such as age
118
Risk factors of shingles
1. Increasing age
2. Immunocompromised
3. HIV, Hodgkin's lymphoma and bone marrow transplants
119
What happens when virus in dorsal root ganglia are activated
travels down affected nerve via sensory root in dermatomal distribution over 3-4 days
CAUSES perineurial and intramural inflammation
120
In HIV patients where is site of reactivation of Herpes Zoster found
Thoracic nerves and trigeminal nerve
121
When can a person with shingles cause chicken pox in another person
if they have a weeping shingles rash
122
Clinical presentation of Herpes Zoster
1. Pain and paresthesiae in dermatomal distribution priced rash (if thoracic then chest and abdo)
2. Malaise, myalgia, headache and fever
3. Rash - papules and vesicles restricted to the same dermatome
4. Neuritic pain
5. Crust formation and drying over next week (takes 2-3 weeks to resolve)
6. RASH does not extend out of dermatome
123
Differential diagnosis of herpes zoster
1. Initial pain in chest or abdo could be cholangitis or renal stones
2. Cluster headaches or migraines
3. Atopic eczema, contact dermatitis or herpes simplex/impetigo
124
Diagnosis of herpes zoster
1. Eruption of rash is diagnostic
125
Treatment of herpes zoster
IMMEDIATE ANTIVIRAL TEHRAPY
1. Oral ACICLOVIR X5 DAILY
Done to minimise risk of peripheral herpetic neuralgia
Topical antibiotic treatment for secondary bacterial infection
Analgesics
126
Complications of herpes Zoster
1. ophthalmic branch of trigeminal - SIGHT
2. Post herpetic neuralgia (pain lasting more than 4 months after shingles, burning pain and does Not respond to analgesics)
127
How is PNH treated
1. Antidepressant (AMYTRYPTYLINE)
2. GABAPENTIN - anti eplieptic)
3. ORAL CARABMAZEPINE (anti-convulsant)
128
What is the main outcome of cerebellar dysfunction
ATAXIA
129
What ion channels are found in purkyne cells
Calcium ion channels
130
Clinical presentation of cerebellar ataxia
1. Staccato speech
2. Choking bouts
3. Oscillopsia
4. Clumsiness
5. Action Tremors
6. Loss of fine movement
7. Unseatdiness when walking (worse in dark)
8. Stumbles and falls
131
What is staccato speech
SLURRING
132
What is choking bouts
Swallowing difficulties
133
What is oscillopsia
Visual disturbances where objects tend to vibrate
134
How do we examine cerebellar ataxia
1. Gait
2. Limb ataxia (truncal, limb and gait ataxia)
3. Eye movements (nystagmus)
4. Speech (dysarthria)
5. Sensory ataxia
135
What is mild ataxia
Only one walking aid needed for independent movement
136
What is moderate ataxia
Mobilised and needs a walking frame
137
What is severe ataxia
Wheelchair dependant
138
What ways can cerebellar disorders be inherited
1. Recessive
2. Dominant
3. Mitochondrial
4. X-linked
139
Example of autosomal recessive ataxia
Friedrich's ataxia
Ataxia of gait and limb - absent reflexes
140
Example of autosomal dominant ataxia
1. Spinocerbellar ataxia 6
Slowly progressive form 40
141
What toxicities can cause ataxia
1. Alcohol
2. Phenytoin
3. Lithium
142
Examples of immune-mediated cerebellar disorder
1. Gluten ataxia
143
Clinical presentation of neruodegerenative ataxia
1. Ataxia
2. Bulbar symptoms
3. Resp hypoventialtion
4. Characteristic MRI finding
144
Diagnosis of cerebellar ataxia
1. MRI to exclude tumours, hydrocephalus, MS etc
145
What causes Friedrich's ataxia
DIABETES
| CARDIOMMYOPATHY
