Brainscape's Knowledge GenomeTM

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


See full index

Infectious Diseases > Meningitis > Flashcards

Meningitis Flashcards

1
Q

Why must meningitis be urgently diagnosed ?

A

It is close in proximity to the brain and spinal cord. Damage to these areas can cause serious neurological damage or potential death.

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

What conditions mimic Meningitis?

A

Conditions such as sub-arachnoid haemorrhage and stroke mimic Meningitis.

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

Outline the steps in diagnosing Meningitis?

A
  1. Lumbar puncture
  2. Processing of the CSF
    - Appearance of the sample
    - Cell count
    - Centrifugation
    - Gram stain and microscopy
    - Culture
    - Further tests based on microscopy results
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How is a lumbar puncture carried out and what is its purpose?

A

a. Allows samples of cerebrospinal fluid to be obtained

b. A spinal needle is inserted between the 3rd and 4th lower vertebrae to obtain samples.

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

Where is a lumbar puncture sample taken from?

A

Between the 3rd and 4th lower vertebrae.

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

Outline what happens with each of the 4 lumbar samples taken to diagnose Meningitis.

A
  1. Chemistry, serology
  2. Gram staining, AFB staining, India ink preparation, bacterial / fungal culturing, culture for tuberculosis
  3. Total cell count, differential count
  4. Cytology, immunology, additional tests
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

For what are CSF samples assessed in terms of their appearance when diagnosing Meningitis ?

A

Examined for turbidity, coloration and clots.

Healthy is clear and colourless

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

What is the purpose of a cell count in Meningitis diagnosis ?

A

Number and type of cells help determine if Meningitis is present and a possible cause.

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

When does centrifugation of CSF samples occur in Meningitis diagnosis ?

A

Once cell counts have been determined.

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

On what samples is centrifugation done in meningitis diagnosis?

A

Only applies to >0.5ml samples

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

What is the purpose of sample centrifugation in Meningitis diagnosis?

A

Used to identify the difference between markedly blood stained and mildly stained samples. This becomes obvious when the supernatant is formed.

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

What is the importance of sample centrifugation in Meningitis diagnosis?

A

i. Concentrates the samples

ii. Increases sensitivity Gram stains and culturing meaning you are more likely to isolate the pathogen

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

If tuberculosis meningitis is suspected, what type of staining is done and why?

A

b. In tuberculosis meningitis is suspected then acid-alcohol-fast bacilli staining is done at the same time. This is needed because microbacterium tuberculosis have a waxy envelope so don’t adhere to Gram staining.

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

What happens in culturing of CSF samples in Meningitis diagnosis?

A

Supernatant inoculated onto Chocolate agar and incubated in Carbon Dioxide for 48 hours.

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

Why is chocolate agar used for culturing in Meningitis diagnosis?

A

All potential pathogens that are being isolated grow on Chocolate agar.

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

What are the 5 potential pathogens that cause Meningitis?

A
  1. Haemophilus influenzae
  2. Neisseria meningitidis
  3. Streptococcus pneumoniae
  4. Listeria monocytogenes
  5. Strep Group B
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Why isn’t enrichment broth used in the culturing of samples used to diagnose Meningitis?

A

Enrichment broth is not advisable because it hardly ever works and there is risk of contamination.

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

What types of further testing may be done on CSF samples to diagnose Meningitis?

A 
Antigen testing
Molecular testing
Viral meningitis testing
Tuberculosis testing
Cryptococcal meningitis testing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

When may molecular testing be used to diagnose Meningitis?

A

Considered optimal for patient management where no causative agent can be found.

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

Describe the symptoms of viral meningitis.

A

Symptoms often mild and not diagnosed.

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

Describe the levels of white cells, glucose and protein in viral meningitis.

A

Increased white cells, glucose levels are normal but protein levels will be raised.

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

Which part of the CSF sample can be used for virological analysis to diagnose meningitis?

A

Supernatant

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

When may antigen testing be used to diagnose Meningitis?

A

In cases where neutrophils are high and protein may be high but no bacteria has been isolated.

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

In some cases of bacterial Meningitis, why is the bacteria often not found?

A

Bacteria may not have been isolated because patients may have already received antibiotics or early meningitis may mean that insufficient microorganisms are present.

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

Describe how commercial antigen kits work to diagnose Meningitis and identify bacteria present in a sample

A

Commercial antigen kits. Antigens against pathogen capsules which are highly antigenic allow agglutination tests against the pathogen to be used. Give a +ve where microscopy and culture are -ve.

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

What is often used to aid diagnosis of tuberculosis meningitis and why?

A

PCR is used more often as it provides fast, specific and sensitive results.

27
Q

In what patients does Cryptococcal meningitis usually occur?

A

Typically occurs in immunosuppressed patients or patients with cell-mediated immunity defects

28
Q

How is Cryptococcal meningitis often diagnosed?

A
  • Gram stain of the CSF – presence of typical yeast cells
  • Confirmed by india ink preparation
  • Antigen tests can also be carried out
29
Q

How would you expect blood in the CSF to look after a Traumatic lumbar puncture ?

A

Blood more in initial tubes as compared to later tubes.

Blood clots on standing.

30
Q

How would you expect blood in the CSF to look after a Subarchnoid haemorrhage?

A

Blood uniform in all tubes; blood does not clot on standing.

31
Q

How would you expect supernatant after centrifugation look within 1 hour of collection in the case of a traumatic lumbar puncture ?

A

Clear

32
Q

How would you expect supernatant after centrifugation look within 1 hour of collection in the case of a Subarachnoid haemorrhage?

A

Pink or yellow (Xanthochromia): yellow Xanthochromia develops 12 hours after haemorrhage.

33
Q

How would you expect a microscopy sample of blood from a CSF sample to look in the case of a traumatic lumbar puncture?

A

Progressive decrease of red cell counts in later tubes.

34
Q

How would you expect a microscopy sample of blood from a CSF sample to look in the case of a Subarachnoid haemorrhage ?

A

Red cell counts uniform in all tubes; haemosiderin-laden macrohages present.

35
Q

Describe the CSF pressure and CSF protein levels in a traumatic lumbar puncture sample

A

Both normal

36
Q

Describe the CSF pressure and CSF protein levels in a Subarachnoid haemorrhage sample.

A

Both increased

37
Q

Describe the health and safety requirements when working with N. meningitidis.

A

All suspected N. meningitidis must be handled in a Class II safety cabinet

38
Q

What is meant by the term sequelae ?

A

A condition which is the consequence of a previous disease or injury

39
Q

What may occur if Meningococcal tissue damage is untreated?

A

If untreated may become necrotic and amputation may be necessary

40
Q

What is necrotic tissue and why does it occur?

A

Having necrotic tissue is a medical condition in which there are dead cells in your body organ. The death of the cells happens due to lack of oxygen and interrupted blood supply

41
Q

In what type of areas is meningitis likely to have a high prevalence?

A
  • Overcrowding – large number of people in close proximity
    o Halls of residence
    o Pilgrimage
    o Barracks
42
Q

In what Geographical locations is Meninigits highly prevalent?

A

o High association of Strep pneumonia with HIV in sub Saharan Africa
o Neisseria meningitidis epidemics common in sub Saharan Africa
o TB meningitis in South East Asia

43
Q

In what age groups does Meningitis have a high prevalence?

A 
o	Neonates particularly susceptible
o	Toddlers
o	Young adults
o	Elderly
As well as the immunocompromised and pregnant.
44
Q

In what people is Neisseria meningitidis common?

A

Common in very young (<2 years old) and the elderly

45
Q

How are the different types of Neisseria meningitidis divided?

A

Divided into serogroups according to polysaccharide outer capsule

46
Q

In what region are Neisseria meninditidis commensal?

A

In the upper respiratory tract, specifically the back of the throat

47
Q

What is peak season for contracting N.meningitidis in the UK?

A

Jan to March

48
Q

When does infection with N.meningitidis become life threatening?

A

When bacteria invade the CSF or blood.

49
Q

How is N.meningitidis spread in the UK?

A

Spread among people living in close contact.

50
Q

What is the major cause of death in terms of Meningococcal disease?

A

Sepsis

51
Q

Where are H.influenzae commensal and what is their resevoir?

A

Commensals of the throat.

Man is resevoir.

52
Q

How are H.influenzae virulent?

A

They impede phagocytosis

53
Q

How is Haemophilus influenzae transmitted?

A

Droplets

54
Q

Why are the numbers of viral meningitiis unreliable?

A

Very few are diagnosed so figures are difficult to obtain. Under-reported because symptoms can be very mild. So the numbers obtained are only from severe cases.

55
Q

What are the symptoms of Meningitis?

A
  • Vomiting
  • Headache
  • Lethargy
  • Confusion / Altered mental status
  • Stiff neck
  • Fever
56
Q

What are the symptoms of Meningococcal Septicaemia?

A
  • Headache
  • Neck stiffness
  • Photophobia – may be absent but the rash may be extensive
  • Bleeding can occur
  • May become comatose
57
Q

When was the MenC vaccine released in the UK?

A

1999

58
Q

Who does the MenC vaccine target?

A

o It was first targeted to everybody up to the age of 18, and to all first year University students.
o This has since extended to include everybody under the age of 25 and people with an increased risk of infection.

59
Q

How many MenC vaccines are used in the UK?

A

3

60
Q

What does MenC vaccine protect against?

A
  • The MenC vaccines only protects against meningococcal diseases caused by serogroup C.
61
Q

Who is the MenB vaccine offered to?

A

The MenB vaccine is offered to babies alongside their routine vaccines at 2, 4 and 12 months.

62
Q

Who is the Men ACWY vaccine offered to ?

A

Offered to the NHS, teenagers and first-time students

63
Q

WHat are the clinical compilations of the Haemophilus influenzae vaccination ?

A

o Hearing loss
o Delayed language
o Mental retardation
o Seizures

Infectious Diseases (9 decks)

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