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1
Q

what area of the CNS is infection during Encephalitis ?

A

inflammation / infection of brain substance

2
Q

what area of the CNS is infection during Meningitis ?

A

inflammation / infection of meninges

3
Q

what area of the CNS is infection during Myelitis ?

A

inflammation / infection of spinal cord

4
Q

what is the classical triad of meningitis ?

A

fever
neck stiffness
altered mental state

5
Q

what the of rash do people get during a meningitis ?

A

Petechial skin rash

6
Q

what test is done to test for the petechial skin rash?

A

tumbler test

- non blanching

7
Q

what type of meningitis is the petechial rash commonly seen?

A

the bacteria meningitis

8
Q

as well as the classical triad of symptoms, what other symptoms can be seen during meningitis ?

A
confusion 
declining consciousness 
cranial nerve palsy 
seizures 
focal symptoms
9
Q

what are the four main categories of aetiology for meningitis ?

A

infective
inflammatory
drug induced
malignant

10
Q

what drugs can induce meningitis ?

A

NSAIDs and IVIG (Intravenous Immunoglobulin)

11
Q

what are the three infective agents that can cause meningitis ?

A

bacterial
viral
fungal

12
Q

what group of people usually are infected by fungal meningitis ?

A

immunosuppressed people

13
Q

what is the virus that causes viral meningitis ?

A

enteroviruses

14
Q

what two bacteria can cause bacterial meningitis ?

A
Neisseria meningitidis (meningococcus)
Streptococcus pneumoniae (pneumococcus)
15
Q

what are the symptoms of meningitis ?

A
fever 
headache 
neck stiffness 
petechial skin rash 
confusion
16
Q

what are the symptoms of encephalitis ?

A

flu like stage in first couple of weeks

confusion
abnormal behaviour
seizures
focal symptoms (vision, hearing)

17
Q

is the onset of viral encephalitis faster or slower than bacterial meningitis ?

A

viral encephalitis is slower

18
Q

is cerebral dysfunction more prominent in viral encephalitis or bacterial meningitis ?

A

viral encephalitis

19
Q

what are the four main categories of the aetiology of encephalitis ?

A

infective
inflammatory
metabolic
malignant

20
Q

what is an inflammatory cause of encephalitis ?

A

limbic encephalitis

21
Q

what is the most common infective cause of encephalitis ?

A

herpes simplex virus

22
Q

what three metabolic problems could cause encephalitis ?

A

hepatic
uraemia
hyperglycaemic

23
Q

what are the two antibodies that can cause autoimmune encephalitis ?

A

anti - VGKC (voltage dated K channels)

anti - NMDA

24
Q

what are the clinical signs of anti-VGKC encephalitis ?

A

frequent seizures
amnesia
altered mental state

25
Q

what are the clinical signs of anti-NMDA encephalitis ?

A

flu like stage
prominent psychiatric features
altered mental state
result in coma

26
Q

what investigations would be done for meningitis ?

A

blood cultures

lumbar puncture

27
Q

should the blood tests and lumbar puncture be done as soon as possible?

A

yes

- they want to be done before antibiotics have started to be given

28
Q

when should a CT scan be done for meningitis ?

A

if there is a contraindication for lumbar puncture

29
Q

what are the investigations that should be done for encephalitis ?

A

blood cultures
imaging (CT/MRI)
lumbar puncture
EEG

30
Q

what two tests can be done on the CSF from a lumbar puncture ?

A

CSF microscopy

CSF culture

31
Q

what are some contraindications for lumbar puncture ?

A
papilloedema
GCS <10 
severe immunocompromised 
new onset seizures 
focal neurological deficit
32
Q

what does focal symptoms suggest about the brain?

A

suggest a focal brain mass/tumour

33
Q

what does reduced conscious level suggest?

A

raised intracranial pressure

34
Q

is the opening pressure of the CSF increased, decreased or normal with bacterial meningitis ?

A

increased

35
Q

is the opening pressure of the CSF increased, decreased or normal with viral meningitis or encephalitis ?

A

normal/increased

36
Q

what WBC is high in CSF of bacterial meningitis?

A

neutrophils

37
Q

what WBC is high in CSF of viral meningitis/ encephalitis ?

A

lymphocytes

38
Q

is glucose levels in CSF increased, decreased or normal with bacterial meningitis?

A

decreased

- sometimes zero

39
Q

is glucose levels in CSF increased, decreased or normal with viral meningitis/ encephalitis ?

A

normal

40
Q

is protein levels in CSF increased, decreased or normal with bacterial meningitis?

A

high

41
Q

is protein levels in CSF increased, decreased or normal with viral meningitis/ encephalitis ?

A

slightly increased

42
Q

what type and shape of bacteria causes bacterial meningitis ?

A

gram positive cocci in chains

43
Q

what is the commonest cause of encephalitis in europe ?

A

herpes simplex virus

44
Q

should treatment of encephalitis be started on suspicion ?

A

yes

- even if the lumbar puncture results aren’t back yet

45
Q

what is the mortality of herpes simplex encephalitis ?

A

70%

46
Q

what antibiotic should be started for herpes simplex virus?

A

aciclovir

47
Q

are HSV encephalitis and bacterial meningitis easy to treat in the early stages ?

A

yes

48
Q

how many types of HSV are there?

A

two types

- type 1 and 2

49
Q

once someone is infected with herpes group of viruses can they be cured?

A

no they are always infected

50
Q

where abouts does the herpes virus lie latent to cause cold sores and genital herpes ?

A

trigeminal and sacral ganglion

51
Q

what type of herpes simplex virus causes encephalitis ?

A

type 1

52
Q

are enteroviruses DNA or RNA viruses ?

A

RNA

53
Q

how are enteroviruses spread?

A

faecal oral route

54
Q

do enteroviruses cause GI symptoms ?

A

no

55
Q

what part of the history is very important to ask about when talking about CNS infections ?

A

travel history

sexual history

56
Q

how are arbovirus encephalitides transmitted ?

A

by a vector such as a mosquito or ticks

57
Q

give some examples of arbovirus encephalitides?

A
West Nile virus
St Louis Encephalitis
Western Equine Encephalitis 
Tick Borne Encephalitis
Japanese B Encephalitis
58
Q

what is an important factor when thinking about uncommon infections from other countries ?

A

immigration

59
Q

what is a brain abscess?

A

localised area of pus within the brain

60
Q

what is a sub dural empyema ?

A

thin layer of pus between the dura and arachnoid membranes over the surface of the brain

61
Q

what symptoms can be caused by a brain abscess?

A

increased intracranial pressure
decreased conscious level
focal symptoms dependant on the area of brain affected

62
Q

what are the clinical symptoms of a brain abscess?

A
fever 
headache 
seizures 
hemiparesis 
decreased conscious level
63
Q

what are three underlying causes of a brain abscess?

A

poor dentition
sinusitis
(middle) ear infection

64
Q

what are two differential diagnoses of a brain abscess or empyema ?

A
subdural haematoma 
focal lesson (tumour)
65
Q

what are some causes of a brain abscess?

A

penetrating head injury
spread of infection from adjacent structures
blood borne infection
post surgery

66
Q

what investigations should be done for a brain abscess?

A

CT/ MRI
examination of head/neck
blood cultures
biopsy (drainage of pus)

67
Q

is drainage of a abscess always possible?

A

no

- if the abscess was in the brain stem then the risks of damage would not be worth it

68
Q

what type and group of bacteria are usually found in brain abscesses?

A

streptococci bacteria

- strep milleri group

69
Q

what group of antibiotics are the strep milleri group of bacteria found in brain abscesses sensitive to?

A

penicillin

70
Q

what percentage of brain abscesses contain strepococci bacteria ?

A

70%

71
Q

what are three bacteria in the strep milleri group?

A

Strep anginosus,
Strep intermedius,
Strep constellatus

72
Q

what antibiotics should be given to aerobic bacteria in brain abscesses?

A

Penicillin or ceftriaxone

73
Q

is strep bacteria aerobic or anaerobic ?

A

aerobic

74
Q

what antibiotic should be given to anaerobic bacteria in brain abscesses?

A

metronidazole

75
Q

why are antibiotics sometimes not effective for brain abscesses?

A

sometimes the antibiotic can’t penetrate the abscess properly so high doses are required for penetration

76
Q

what system in the brain reduces the effect of drugs on the brain ?

A

blood brain barrier

77
Q

with which conditions should the patient be offered a HIV test?

A
Cerebral toxoplasmosis 
Aseptic meningitis /encephalitis
Primary cerebral lymphoma 
Cerebral abscess
Cryptococcal meningitis 
Space occupying lesion of unknown cause
Dementia 
Leucoencephalopathy
78
Q

what brain infections are common in HIV patients with low CD4 counts ?

A
Cryptococcus neoformans
Toxoplasma gondii
Progressive multifocal leukoencephalopathy (PML)
Cytomegalovirus (CMV)
HIV-encephalopathy
79
Q

are PCR tests specific ?

A

yes very specific

80
Q

what tests should be done to investigate infections associated with HIV?

A
India Ink
Toxoplasmosis serology (IgG)
JC virus PCR 
CMV PCR 
HIV PCR
81
Q

what bacterial antigen is detected using the india ink test?

A

cryptococcal antigen

82
Q

what type of organism is cryptococcal ?

A

fungi

83
Q

what is the transmission route for fungi?

A

inhalation from dust

84
Q

form what object do immunocompromised people in aberdeen commonly get a fungal brain infection?

A

opening brown bins full of compost

85
Q

what bacteria causes lyme disease ?

A

Borrelia burgorferi

86
Q

what bacteria causes syphilis ?

A

Trepomena pallidum

87
Q

what bacteria causes leptospirosis ?

A

Leptospira interrogans

88
Q

how many stages are there for lames disease?

A

3

89
Q

how is lyme disease transmitted?

A

vector borne

- ticks

90
Q

what type of rash is seen in stage 1 lyme disease ?

A

erythema migrans

91
Q

where is the erythema migrans rash seen on the patient ?

A

where the tick bite was

92
Q

what type of symptoms are seen in stage 1 lyme disease ?

A

flu like symptoms

  • fatigue
  • headache
  • fever
  • chills
  • neck stiffness
93
Q

how long does stage 1 lyme disease last for ?

A

1 month

94
Q

how does the bacteria form the tick spread around the body after the initial bite?

A

blood and lymphatics

95
Q

what are the common symptoms in stage 2 lyme disease ?

A

joint and muscle pain

neurological involvement

96
Q

during lyme disease, is the PNS or CNS more effected ?

A

PNS

97
Q

how long does stage 2 lyme disease last for?

A

weeks - months

98
Q

how long does stage 3 of lyme disease last for?

A

months - years

99
Q

does lyme disease cause chronic fatigue syndrome ?

A

no

100
Q

what two conditions of neurological involvement is seen in stage 3 lyme disease

A

Subacute encephalopathy

Encephalomyelitis

101
Q

what investigations should be done for lyme disease ?

A
serology 
CSF lymphocytosis 
PCR of CSF 
MRI spine and brain 
nerve conducting studies
102
Q

what is the treatment for stage 1 and 2 lyme disease

A

oral doxycycline

103
Q

what is the treatment for stage 3 lyme disease ?

A

1 month IV ceftriaxone

104
Q

how many stages of presentations are there for syphilis ?

A

3

105
Q

what is syphilis treated with?

A

high dose penicillin

106
Q

what blood tests can be done for syphilis ?

A

Treponema specific and non-treponemal specific (VDRL) antibody tests

107
Q

what type of virus is poliovirus ?

A

enteroviruses

108
Q

what symptoms does polio cause ?

A

flaccid paralysis

- no sensory features

109
Q

what can the polio vaccine be given ?

A

injection

orally

110
Q

what part of the nervous system does the polio virus affect?

A

anterior horn cells of lower motor neurones

111
Q

how is rabies transmitted to humans ?

A

bite

saliva

112
Q

what part of the nervous system does the rabies virus affect?

A

infects the peripheral nerves and migrates to CNS

113
Q

what are the clinical symptoms of rabies ?

A

ascending paralysis and encephalitis

114
Q

how is the rabies infection managed ?

A

sedation
intensive care
death

115
Q

what mammals commonly transmit the rabies virus ?

A

dogs and bats

116
Q

in what form is the rabies virus given in the vaccine ?

A

killed vaccine

117
Q

who should be given the rabies vaccine?

A

people travelling abroad to areas where rabies incidence is high
bat handlers
regular handlers of imported animal s

118
Q

what are the three steps of suspected rabies from a dog bite ?

A
  1. wash wound
  2. give active rabies immunisation
  3. give human rabies immunoglobulin
119
Q

what type of bacteria is clostridium tetani?

A

anaerobic gram positive bacillus, spore forming

120
Q

where about does the toxin of tetanus act in the nervous system ?

A

acts at the NMJ

121
Q

what are the clinical symptoms of tetanus?

A

rigidity
spasm
risus sardonicus

122
Q

what is risus sardonicus ?

A

highly characteristic, abnormal, sustained spasm of the facial muscles that appears to produce grinning

123
Q

What two medications should be given to suspected tetanus patients ?

A

penicillin

immunoglobulin

124
Q

what bacteria causes botulism ?

A

clostridium botulinum

125
Q

what type of bacteria is clostridium botulinum ?

A

Anaerobic spore producing gram positive bacillus

126
Q

What are the three routes of infection of botulism ?

A

infant intestinal colonisation
food borne
wound - common in drug users

127
Q

why are drug users high risk for botulism ?

A

when they inject the drugs, if they miss the vein then the drugs can cause an abscess to form and the bacteria to colonise

128
Q

what are the common clinical signs of botulism ?

A

pupil dilation

descending symmetrical flaccid paralysis

129
Q

does botulism affect the sensory and motor fibres ?

A

just the motor fibres

130
Q

how is botulism diagnosed ?

A

culture from debrided wound

nerve conduction study

131
Q

what are the three treatment options for botulism ?

A
  1. anti-toxin (A,B,E)
  2. penicillin/ metronidazole (prolonged treatment)
  3. radical wound debridement
132
Q

state two post infective inflammatory syndrome which can occur after an infection?

  1. CNS
  2. PNS
A

CNS
- Acute disseminated encephalomyelitis (ADEM)

PNS
- Guillain Barre Syndrome (GBS)

133
Q

what type of condition is post infective inflammatory syndrome?

A

autoimmune

134
Q

state some symptoms of Guillain Barre Syndrome (GBS)?

A

pain, tingling and numbness
progressive muscle weakness
co-ordination problems and unsteadiness

135
Q

what is the most common cause of CJD ?

A

sporadic CJD

136
Q

is CJD disease common?

A

no very rare

1 per million

137
Q

is the presentation of sporadic CJD all the same ?

A

no it varies

138
Q

what age range is CJD most common?

A

> 60yrs

139
Q

what substance causes CJD ?

A

Transmissible Proteinaceous particle – Prion

140
Q

what symptoms would someone with CJD experience ?

A
myoclonus (jerks)
weakness 
hyper reflexia 
blindness 
seizures 
confusion 
tremor
141
Q

what disease should be considered in someone over 60yrs who has rapidly progressive dementia ?

A

sporadic CJD

142
Q

what is the prognosis and survival time for sporadic CJD?

A
  • poor due to rapid progression

- death within 6 months

143
Q

what are some differential diagnoses of sporadic CJD?

A
Alzheimers with myoclonus 
Subacute sclerosing panencephalitis (SSPE)
CNS vasculitis 
Non-convulsive status 
Inflammatory encephalopathies
144
Q

what three investigations should be done to test for CJD?

A

MRI
EEG
Lumbar puncture

145
Q

for CJD infection will the protein in the CSF be normal ?

A

normal or raised

146
Q

what would be seen on a MRI with a patient who has variant CJD?

A

pulvinar sign

147
Q

what age range is at most risk for new variant CJD?

A

younger onset <40yrs

148
Q

what is a common way for people to become infected with new variant CJD?

A

eating infected meat

149
Q

does new variant or sporadic CJD have a longer course and therefore less severe?

A

new variant has a longer course

150
Q

is Guillain Barr syndrome anaerobic or aerobic infection ?

A

aerobic

151
Q

which infection would have flu like symptoms before neurological signs ?

A

viral encephalitis

lymes disease

152
Q

should antibiotics be started while waiting for a CT and a lumbar puncture for viral encephalitis ?

A

yes

153
Q

what infection are drug users high risk for contracting ?

A

botulism

154
Q

what rash is seen during lymes disease ?

A

erythema migrans

155
Q

what virus is the most common cause for viral encephalitis ?

A

herpes simplex

156
Q

what group of bacteria is most common in brain abscesses?

A

strep milleri

157
Q

can poliomyelitis be vaccinated against ?

A

yes

158
Q

does bacterial meningitis increase CSF opening pressure?

A

yes

159
Q

does viral encephalitis increase CSF opening pressure?

A

no