Meningitis - beckham

Question 1

1. Discuss the clinical presentation, most common organisms for different age groups, basic CSF profile (cell number and type, glucose, protein) for bacterial meningitis and basic medical management for bacterial meningitis in different age groups
2. Discuss the clinical features, most common viruses, basic CSF profile, and key diagnostic tests for viral meningitis and viral encephalitis
3. Discuss the basic clinical features, diagnostic tests, and initial antimicrobial therapy for patients with a focal suppurative CNS infection (e.g., brain abscess, empyema)

Answer 1

x

Question 2

What is the most common cause of sporadic encephalitis in the US?

What is the most common cause of epidemic encephalitis in the US?

Answer 2

HSV-1

WNV (June - September in West/Midwest)

Question 3

What is the diagnostic test of choice for encephalitis?

Answer 3

Trick question. Depends on the type.

HSV-1 = PCR
WNV = CSV IgM

[For WNV PCR is CRAP. By the time you see them, the viremia is gone. IgM doesn’t cross the BBB even when inflamed. Vaccination shouldn’t produce CSF IgM. So, if you see IgM on a CSF, you know it was manufactured in the CSF. Therefore the test is very specific THIS WILL BE ON THE TEST I GUARANTEE IT]

Question 4

What is the clinical/subclinical/fatal profile of WNV?

Answer 4

80% asymptomatic
20% headache/fever
1% CNS (encephalitis)
0.1% fatal CNS infections

Question 5

What is the appearance of the following infections on MRI?

WNV
HSV

Answer 5

WNV - Early stages = normal. Late stages may see changes in the deep grey matter (thalamus, BG, midbrain

HSV - See temporal lobe changes

Question 6

What is the CSF profile of WNV encephalitis?

Answer 6

Pleocytosis (PMN exceed 2000)
Glucose normal
Protein elevated (50-250 mg/dL)

Question 7

Are there effective therapies for WNV?

Answer 7

not really.

Question 8

If viral encephalitis (WNV) is on the differential, what drug should immediately be started?

Answer 8

Acyclovir.

Question 9

HSV-2 in adults tends to cause _____.

HSV-1 in adults tends to cause _____.

Answer 9

HSV-2: meningitis

HSV-1: encephalitis

Question 10

What is the CSF profile for viral meningitis?

Answer 10

Pleocytosis (PMN)
Normal Glucose
Normal/elevated protein.

**WNV lecture says elevated protein, not sure about the discrepancy, but WNV is included in this broad categorization slide

Question 11

What are the two most common causes of viral meningitis in adults?

Answer 11

1. Enteroviruses

2. HSV-2

Question 12

What signs and symptoms might one see with an enterovirus meningitis?

Answer 12

IN kids, can often see rash, pharyngitis, myocarditis, pericarditis
Echovirus–> rash
Cxsackievirus–> herpangina – bumps in the mouth/back of throat (shown)

Question 13

What is the diagnositic modality of choice for Enterovirus-caused meningitis?

Answer 13

PCR. Quite good s/s.

Question 14

Which is the more severe, HSV encephalitis or meningitis?

Answer 14

HSV Meningitis –> Mild

HSV Encephalitis –> Extra bad is REALLY SEVERE and people do REALLY BADLY and DIE and SHIT

Question 15

What is the tx for HSV meningitis?

Answer 15

Valacyclovir.

Acyclovir? [Please note that ACyclovir is THE definitive tx for HSVEncephalitis]

Question 16

What noninfectious condition can mimic viral encephalitis?

Answer 16

Autoimmune encephalitis.

{Anti-NMDA Receptor Encephalitis:
Prominent psychiatric symptoms, cognitive, seizures, orofacial dyskinesias, autonomic instability
CSF profile looks like viral encephalitis
Diagnosis: serum/CSF testing for the antibody
Treatment: immune suppression]

Question 17

What is notable about the epidemiology of HSV encephalitis?

Answer 17

No seasonal or geographic predilection.
Bimodal age distribution less than 20 or over 50
40% of all encephalitis cases are HSV in pop. over 60y/o

Question 18

What diagnostic tests are good for HSV encephalitis?

Answer 18

MRI is good 90%. Temporal lobe lesions.

PCR also good 90% (even up to 10 days post-symptoms)

Biopsy was old school, had problems with false negatives.

Question 19

When in doubt as to whether your patient might have HSVE?

Answer 19

Acyclovir. Safe, no harm in administering.