26 Bacterial and fungal meningitis Flashcards Preview

Clinical Pathology > 26 Bacterial and fungal meningitis > Flashcards

Flashcards in 26 Bacterial and fungal meningitis Deck (21)
Loading flashcards...
1
Q

What are the CSF findings in bacterial meningitis?

A

Very high polymorph count.

i.e. mainly neutrophils, also basophils + eosinophils

2
Q

What is the main cause of bacterial meningitis?

Where is carriage, and what %?

A

Neisseria meningitidis.

Nasopharynx. Below 20% are carriers, but increased above 20% amongst smokers and before outbreak.

3
Q

How does N meningitidis survive intravascularly?

A

Capsule protects against complement based attack.

Acquires iron from transferrin.

4
Q

What does N meningitidis usually cause alongside meningitis?

A

Fulminant septicaemia ± purpuric rash.

5
Q

What is the treatment for N meningitidis meningitis?

A

Ceftriaxone, cefotaxime, penicillin.

6
Q

What is the prophylaxis and vaccination for N meningitidis?

A

Rifampicin + ciprofloxacin.

Active against Group A+C+W135.

7
Q

Which other bacteria cause meningitis besides N.meningitidis? (2)

A
Haemophilia influenzae (type b is most invasive, most are non-capsulate).
Streptococcus pneumoniae (most are capsulate).
8
Q

Who gets meningitis caused by haemophilus influenzae?

A

Infants.

9
Q

What are the virulence factors that H influenzae has? (3)

A

Type b capsule.
Fimbriae.
IgA proteases.

10
Q

What is the treatment for H influenzae meningitis? (3)

A

Ceftriaxone, cefotaxime, ampicillin.

β-lactamase producing strains common

11
Q

Which meningitis causing organism is identifiable by the optochin test?

A

Streptococcus pneumoniae.

12
Q

Who gets meningitis caused by Streptococcus pneumoniae?

A

Elderly.

Immunocompromised.

13
Q

Which type bacterial cause of meningitis has no chemoprophylaxis available?

A

Streptococcus pneumoniae.

14
Q

Why are steroids used in meningitis? (2)

How do they alter antibacterial Rx?

A

Strep pneumoniae pathology partly due to immune system.
Dexamethasone decreases mortality.
If vancomycin used add rifampicin as dexamethasone decreases vanc levels in CSF.

15
Q

What are the causative organisms of neonatal bacterial meningitis? (3)

A

Group B haemolytic Streptococci.
Escherichia coli.
Listeria monocytogenes.

16
Q

What is the treatment for neonatal meningitis?

A

Cefotaxime.

Ampicillin and gentamicin.

17
Q

Which fungus causes meningitis, and in who?

Diagnosis?

A

Cryptococcus.
Late stage HIV patients.
Indian Ink stain of CSF.

18
Q

How does cryptococcal meningitis present?

Treatment?

A

Insidious onset, lymphocytic.

Amphotericin, flucytosine or fluxconazole.

19
Q

What causes a meningitis with a CSF cell count >200 consisting of mostly polymorphs and reduced glucose?

A

Bacteria.

20
Q

What causes a meningitis in which the CSF protein count may be normal?

A

Viruses.

21
Q

What are the causes of a meningitis with CSF findings: high lymphocyte count, reduced glucose and increased protein?

A

Viruses.
TB.
Cryptococcus.

Decks in Clinical Pathology Class (66):