Viral meningitis Flashcards Preview

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Flashcards in Viral meningitis Deck (31):
1

What is aseptic meningitis?

Clinical meningitis but not bacterial source

2

What are possible causes of aseptic meningitis? (8)

Viruses
Partially treated bacterial meningitis
Listeria
TB
Autoimmune
Malignancy
Syphilis
Drugs

3

2 peak ages of viral meningitis?

Neonate and about 5yo

4

Viruses that cause meningitis (18)

Enteroviruses (echoviruses, coxsackie, parecho, enterovirus 70/71, poliovirus)
Herpes viruses (HSV 2, VZV, CMV, EBV, HHV6/7)
Arboviruses
Mumps
HIV
Adenovirus
Measles
Influenza
Parainfluenza type 3
Lymphocytic choriomeningitis virus

5

Pathogenesis of viral meningitis?

colonisation of mucosal surfaces
invasion of epithelial surface
replication in cells
dissemination and cns invasion (cerebral microvascular endothelial cells, choroid plexus epithelium, olfactory nerve)

Inflammation in CNS=symptoms

6

What are the 3 features of meningism?

Stiff neck
Headache
Photophobia

7

What signs are present in infants (possibly in the absence of meningism)

Nuchal rigidity
Bulging anterior fontanelle

8

What are two clinical tests/signs?

Kernig's sign (hip and knee flexed to 90 degrees, knee can't be extended due to pain/stiffness in hamstrings)

Brudzinski's sign (flexing neck causes hips and knees to flex)

9

What would viral meningitis blood tests show?

WBC count and CRP normal

10

What 4 investigations?

Bloods (tests and culture, MC&S)
CT head
Lumbar puncture ASAP
Viral PCR

11

What does the head CT look for?

Raised ICP- contraindicates an LP as removing CSF can cause brain to herniate through foramen magnum ('coning') and also to look for other diagnoses

12

What is the gold standard test for viral meningitis?

Viral PCR

13

CSF findings in viral meningitis?

Lymphocytic
Protein normal/mildly elevated
Glucose normal/slightly low

14

Most common and second most common cause of viral meningitis in uk?

Enterovirus
HSV2

15

Treatment of viral meningitis?

Supportive
If any risk that it is bacterial then IV Abx
NOTIFIABLE

16

Is aciclovir effective against HSV2 and VZV meningitis?

No evidence that it is

17

Mollaret's meningitis is what?

Recurrent aseptic meningitis, major cause is HSV2

18

4 associated symptoms of HIV meningitis

fever
lymphadenopathy
pharyngitis
rash

19

Prognosis of viral meningitis

Full recovery expected

20

4 causes of viral encephalitis that are not also causes of meningitis?

HSV1
Rubella
Rabies
Acute disseminated encephalomyopathy

21

Major presenting features of encephalitis

Altered mental state
Fever
Headache
Meningism
Focal neurology (seizures, weakness, dysphagia, CN palsy, ataxia)

22

Investigations of viral encephalitis (5)

Blood tests
CT
MRI
LP (MC&S, protein and glucose, viral PCR)
EEG

23

What would EEG show in HSV encephalitis?

75% show abnormal temporal lobe activity

24

Rx viral encephalitis?

High dose IV aciclovir- start on clinical suspicion as is a medical emergency

25

CSF results?

Same as viral meningitis

26

HSV encephalitis prognosis?

High mortality if untreated (70%), even if treated remains high. Best if aciclovir within 4 days

27

HSE peak age?

50

28

HSE pathogenesis

Virus moves along neural/olfactory pathways, reactivated in the trigeminal ganglia
Acute focal necrotising encephalitis

29

What often happens to survivors of HSE?

neurological sequelae e.g. paralysis, speech loss, personality change

30

What is acute disseminated ecephalomyopathy?

Immune-mediate demyelination of CNS, can follow virus or vaccination.
Clinical features same as encephalitis
CSF findings = viral meningitis
MRI helpful

31

Rx ADEM

Steroids/immune suppressants