Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Neurology- Clinical > CNS Infections > Flashcards

CNS Infections Flashcards

1
Q

What makes the immune system of the CNS unique?

A

The brain has no lymphatic system / B cell defence predominates over T cell defence / The BBB tightly controls the entrance of immune cells into the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the purpose of the unique immune system of the CNS?

A

To limit oedema and secondary damage during inflammation of the CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Untreated infection within the CSF may cause what?

A

Brain herniation and death / spinal cord compression and necrosis which can lead to paralysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the difference between meningitis and encephalitis?

A

Meningitis is infection of the meninges / encephalitis is infection of neuronal and glial substance of the brain (i.e. the parenchyma)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is encephalopathy?

A

Irritation of brain parenchyma, not inflammation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the most serious form of meningitis?

A

Bacterial meningitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Bacterial meningitis should be suspected in any patient presenting with features of what? Give examples.

A

Meningism (headache, neck stiffness, photophobia) and sepsis (fever, non-blanching purpuric rash)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is a common presenting triad of bacterial meningitis?

A

Headache, fever and cognitive changes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What usually precedes an episode of bacterial meningitis?

A

A prodrome of a respiratory or ear infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Bacterial meningitis occurs with peaks in who?

A

Infants and adolescents (freshers)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Where can the pathogenesis of bacterial meningitis come from?

A

Nasopharyngeal colonisation, direct extension of bacteria (e.g. sinusitis, mastoiditis, skull fractures) or from remote foci of infection (e.g. endocarditis or pneumonia)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Pyogenic meningitis is another name for bacterial meningitis - what does this refer to?

A

A thick layer of supperative exudate which covers the leptomeninges over the surface of the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Microscopically, pyogenic meningitis can be seen as what?

A

Neutrophils in the subarachnoid space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

When should treatment for suspected bacterial meningitis be started?

A

Ideally within 1 hour - don’t wait for investigations!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the 4 main investigations to do for bacterial meningitis?

A

Bloods, throat swab, CT, LP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What bloods are done for bacterial meningitis?

A

FBCs, Us+Es, LFTs, WCC, CRP, culture, pneumococcal and meningococcal PCR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Name some patient groups who should undergo a CT to exclude a space occupying lesion before having a lumbar puncture?

A

Immunocompromised, history of CNS disease, new seizure, papilloedema, abnormal conscious level or focal neurological deficit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the purpose of the LP for bacterial meningitis?

A

To confirm the diagnosis and guide antibiotic therapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

After an LP, what tubes should you send off for interpretation?

A

2x (tubes 1 and 4) haematology for cell count and differential / tube 2 to microbiology for gram stain and culture / tube 3 to chemistry for glucose and protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What would be the suspected opening pressure on LP in bacterial meningitis?

A

Slightly raised

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Explain the main LP findings you would see in bacterial meningitis?

A

Raised WCC, neutrophils and protein, low glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What 4 organisms make up most of the cases of bacterial meningitis?

A

Haemophilus influenzae, strep pneumoniae, neisseria meningitides, listeria monocytogenes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Where is strep pneumoniae normally found in the body?

A

Nasopharynx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Which patients are more susceptible to infection with strep pneumoniae?

A

Hospitalised patients, skull fractures, diabetics/alcoholics, young children

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

CNS devices e.g. cochlear implants are related to an increased risk of which bacteria?

A

Strep pneumoniae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

N. Meningitides is an intracellular organism - within which cells is it found in the CNS? Symptoms from this organism are actually caused by what?

A

Leukocytes / an endotoxin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Who does N. meningitides meningitis mostly occur in?

A

Children and adolescents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Who is H. influenzae most likely to occur in?

A

Children (especially < 4)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Who are more at risk of getting meningitis caused by listeria?

A

Neonates and those aged > 55, and immunocompromised (especially malignancy)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are some non-conventional agents that may cause meningitis in the immunocompromised?

A

Listeria, mycobacterium TB, cryptococcus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Cryptococcus neoformans most commonly causes meningitis in who? What type of organism is it? How is it treated?

A

Those with HIV and CD4 < 100 / fungus / amphotecerin B/flucytosin and fluconazole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are some features which may raise suspicion of a TB meningitis?

A

Subacute onset, non-specific ill health, poor yield from CSF, CN palsies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Name 3 bacteria which are most likely to cause meningitis in neonates?

A

E.coli, group B strep, listeria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What organism is most likely to cause meningitis in children?

A

Haemophilus influenzae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What organism is most likely to cause meningitis in those aged 10-21?

A

Neisseria meningitides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What organisms are most likely to cause meningitis in those aged 21-65?

A

Strep pneumoniae and neisseria meningitides

37
Q

What organisms are most likely to cause meningitis in those aged 65+?

A

Strep pneumoniae and listeria

38
Q

People who have undergone recent neurosurgery or head trauma are more at risk of meningitis caused by what organisms?

A

Staphylococcus, gram - bacilli

39
Q

People who have undergone a recent fracture of the cribriform plate are more at risk of meningitis caused by what organisms?

A

Strep pneumoniae

40
Q

People who have a CSF shunt are more at risk of meningitis caused by what organisms?

A

Staph epidermidis/aureus, proprionibacterium acnes

41
Q

What is the initial treatment (before antibiotics) for people presenting with bacterial meningitis?

A

ABCDE and start sepsis 6 if necessary

42
Q

What are the major things that are covered in immediate hospital management of bacterial meningitis?

A

Take bloods, give antibotics, take throat swabs, swab or aspirate any skin lesions for microscopy and culture

43
Q

What is the first medical management for bacterial meningitis?

A

Ceftriaxone 2g IV bd with dexamethasone 10mg IV qds

44
Q

What is the first medical management for bacterial meningitis if the patient is penicillin allergic?

A

Chloramphenicol 25mg/kg IV qds with dexamethasone 10mg IV qds

45
Q

When should dexamethasone be started for bacterial meningitis? When should it be used until?

A

At the same time or just before the first dose of antibiotics. If pneumococcal meningitis is confirmed, continue it for 4 days. If not then stop it.

46
Q

When would a patient being treated for bacterial meningitis require extra cover against listeria? What is this cover?

A

If they are aged 60+ or immunocompromised (including alcohol dependency and diabetes) / amoxicillin 2g IV 4 hourly

47
Q

What is the penicillin allergic option to cover listeria?

A

Co-trimoxazole 120mg/kg IV in 4 divided doses

48
Q

If there has been recent travel within the last 6 months, what additional antibiotic would you start a patient who is being treated for bacterial meningitis on?

A

Vancomycin 15-20mg/kg bd IV or rifampicin 600mg bd IV/PO

49
Q

Who, being treated for bacterial meningitis, should not receive steroids?

A

Post-surgery, immunosuppressed, hypersensitivity to steroids, meningococcal or septic shock

50
Q

Gram + diplococcus implies which organism?

A

Strep pneumoniae

51
Q

Gram - cocci implies which organism?

A

Neisseria meningitides

52
Q

Gram - bacillus implies which organism?

A

Haemophilus influenzae (also E.coli)

53
Q

Gram + bacillus implies which organism?

A

Listeria monocytogenes

54
Q

Describe the onset of viral meningitis when compared to bacterial?

A

Slightly more subacute onset, potentially presenting over days

55
Q

What is the outcome of viral meningitis?

A

It is usually self-limiting and patients recover without any neurological complications

56
Q

Describe the presentation of viral meningitis?

A

Similar to bacterial but not as severe - often headache, fever and lack of significant neurological deficit with a mildly raised WCC

57
Q

When is it more common to get viral meningitis?

A

Summer/late autumn

58
Q

What is aseptic meningitis?

A

Essentially a term for any suspected meningitis which is not bacterial (could be viral, but not exclusively)

59
Q

What are the main 3 investigations to do for viral meningitis?

A

CSF PCR, throat swab and viral stool culture

60
Q

Why is a viral stool culture done in the investigation for viral meningitis?

A

Because often the causative virus is enteric to the gut

61
Q

What is the most common organism to cause viral meningitis?

A

Enteroviruses e.g. coxsackie or echovirus

62
Q

What is an important thing to ask about in suspected viral meningitis and why?

A

Travel history - lots of strange viruses which can cause this if the person has travelled

63
Q

What is the treatment for viral meningitis?

A

Supportive

64
Q

What are some viral agents which may cause viral meningitis in the immunocompromised?

A

EBV, CMV, toxoplasma gondii

65
Q

Encephalitis is the inflammation of the brain parenchyma. What can it be caused by?

A

Any infectious agents or an autoimmune process

66
Q

Encephalitis can co-exist alongside what other infections?

A

Meningitis (encephalomeningitis) or inflammation of the spinal cord (encephalomyelitis)

67
Q

What is a sign that is a) more specific to meningitis than encephalitis? b) more specific to encephalitis than meningitis? c) if these are both seen together, what could be a cause?

A

a) neck stiffness b) confusion c) meningoencephalitis

68
Q

What is the onset of encephalitis?

A

Usually has an insidious onset, though can sometimes be sudden

69
Q

What are some potential presenting features of encephalitis?

A

Headache, fever, seizures, focal neurological deficits, deteriorated mental status

70
Q

What is the most serious organism to cause encephalitis?

A

Herpes simplex

71
Q

Herpes simplex encephalitis typically presents with what? This is due to inflammation where in the brain?

A

Seizures and memory/behavioural disturbance / temporal lobe

72
Q

What investigations should be done for encephalitis?

A

Lumbar puncture, EEG, MRI

73
Q

What will a lumbar puncture of encephalitis show?

A

Raised lymphocytes and protein, normal glucose

74
Q

If there are delays in investigations for encephalitis, can treatment be started anyway?

A

Yes

75
Q

What treatment is used for encephalitis? What is the dose of this for someone > 12 years old?

A

Acyclovir - 10mg/kg

76
Q

What are the main complications of CNS infection?

A

Purulence, invasion, cerebral oedema, hydrocephalus

77
Q

After/during a CNS infection, clusters of pus can form at the base of the brain. These can form exudate around nerves - which are most commonly affected?

A

CNs III and VI

78
Q

What structure prevents meningitis from becoming an abscess? What can abscesses cause?

A

The pia mater / secondary vetriculitis and hence meningitis

79
Q

What are the public health rules with regards to bacterial meningitis?

A

All cases should be reported to public health so that contact tracing can be performed for prophylaxis and vaccination

80
Q

What should be done regarding recording close contacts of people with bacterial meningitis?

A

Their records should be labelled to alert doctors of their increased risk for 6 months

81
Q

What is the main prophylactic regimen for adults aged 12+ who have been in close contact to those with bacterial meningitis?

A

Rifampicin PO 600mg 4 doses 12 hourly

82
Q

What is the a second prophylactic regimen for people who have been in close contact to those with bacterial meningitis which is not licensed but has been used in epidemics?

A

Ciprofloxacin PO 500mg as a single dose

83
Q

Vaccines exist for which causes of bacterial meningitis?

A

Haemophilus influenzae, strep pneumoniae and neisseria meningitides

84
Q

What is the main meningococcal vaccination and who is it offered to?

A

MenACWY - offered to adolescents

85
Q

What are polymorphs? These are suggestive of what diagnosis?

A

Neutrophils - bacterial meningitis

86
Q

Pink coloured CSF suggests it is what? What diagnosis does this suggest?

A

Turbid - bacterial meningitis

87
Q

High doses of steroids given short term can cause what?

A

Steroid psychosis / raised blood sugar

88
Q

Milleri strep is suggestive of what?

A

Brain abscess

89
Q

What warnings should you give to patients taking rifampicin?

A

Decreases efficiency of the contraceptive pill, turns body fluids red

Neurology- Clinical (31 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions