CNS Infections

Question 1

Meningitis is inflammation of membranes of the ____ and ____ (in particular the ____)

Answer 1

Spinal cord, brain, leptomeninges

Question 2

Encephalitis is inflammation of the ____

Answer 2

brain

Question 3

Encephalitis is usually caused by

Answer 3

viruses and bacteria

Question 4

Meningitis is caused by

Answer 4

bacteria, viruses, medications (aseptic), fungus

Question 5

What are top 5 most common infectious pathogens that cause meningitis

Answer 5

Strep pneumo, Group B strep, neisseria meningitidis, H. influe, listeria monocytogenes

Question 6

What common pathogen of meningitidis goes down the list as patients grow older? (Becomes less common cause)

Answer 6

Group B strep

Question 7

Describe the pathophysiology of meningitis- what property of the invading organism is advantageous in getting through the bloodstream?

Answer 7

Inflammation of the BBB causes tight junctions to widen which allows bacteria to enter. CSF lacks immune cells/chemicals that prevent replication so bacteria begins to multiply. Organisms can go through the bloodstream unscathed if they are encapsulated.

Question 8

What are the CSF markers related to pathophysiology of meningitis?

Answer 8

Increased CSF protein, decreased CSF glucose increased CSF lactate

Question 9

What are the components of the classic “triad” of meningitis (clinical presentation)?

Answer 9

Fever, nuchal rigidity, AMS, headache

Question 10

Empiric meningitis therapy for Age Group <1 month

Answer 10

Ampicillin + cefotaxime OR ampicillin + AG (gent/tobra)

Question 11

Why should you not use ceftriaxone on infants < 1 month?

Answer 11

Kernicterus

Question 12

Empiric meningitis therapy for Age Group 1-23 months

Answer 12

Vancomycin + 3GC (ceftriaxone or cefotaxime)

Question 13

Why do you not use ceftriaxone alone as empiric treatment for children with meningitis?

Answer 13

There is a chance that S. pneumo has resistance to ceftriaxone

Question 14

Empiric meningitis therapy for Age Group 2-50 years

Answer 14

Vancomycin + 3GC

Question 15

Empiric meningitis therapy for Age Group 2-50 years

Answer 15

Vancomycin + 3GC +

Ampicillin is needed for listeria which shows up in this age group

Question 16

Definitive treatment for S. pneumoniae (penicillin susceptible)

Answer 16

PCN G 4 million units IV q4H OR ampicillin 2 g IV q4h

Question 17

Definitive treatment for N. meningitidis (penicillin susceptible)

Answer 17

PCN G 4 million units IV q4h OR ampicillin 2 g IV q4h

Question 18

Definitive treatment for S. pneumoniae (penicillin resistant)

Answer 18

Vanco + ceftriaxone or cefotaxime

Question 19

Definitive treatment for N. meningitidis (penicillin resistant)

Answer 19

ceftriaxone or cefotaxime

Question 20

Definitive treatment for N. meningitidis (penicillin resistant) in pregnancy

Answer 20

ceftriaxone

Question 21

Definitive treatment for H. flu (b-lactam negative)

Answer 21

ampicillin 2 g IV q 4h

Question 22

Definitive treatment for H. flu (b-lactam positive)

Answer 22

cefotaxime or ceftriaxone

Question 23

Definitive treatment for listeria monocytogenes)

Answer 23

PCN G +/- gentamicin

Question 24

Definitive treatment for group B strep

Answer 24

PCN OR ampicillin

Question 25

Definitive treatment for enterobacteriaceae, e. coli, k. pneumoniae, enterobacter spp.

Answer 25

ceftriaxone or cefotaxime

Question 26

Definitive treatment for pseudomonas aeruginosa

Answer 26

ceftaxidime or cefepime

Question 27

Definitive treatment for acinetobacter baumanii

Answer 27

ampicillin/sulbactam, meropenem, amikacin, or colistin/polymixin

Question 28

Definitive treatment for enterococcus sp (AMP susceptible)

Answer 28

ampicillin + gentamicin

Question 29

Definitive treatment for enterococcus sp (AMP resistant)

Answer 29

vancomycin + gentamicin

Question 30

Definitive treatment for enterococcus sp (VRE)

Answer 30

linezolid, daptomycin, quinupristin/dalfopristin

Question 31

Length of therapy for treating S. pneumoniae

Answer 31

10-14

Question 32

Length of therapy for treating N. meningitidis, H. influenzae

Answer 32

7-10

Question 33

Length of therapy for treating Group B streptococcus, S. aureus

Answer 33

14-21

Question 34

Length of therapy for treating Enterobacteraceae, P. aeruginosa

Answer 34

21

Question 35

Length of therapy for treating listeria monocytogenes

Answer 35

>/=21

Question 36

Advantages of corticosteroid therapy in patient with meningitis

Answer 36

Reduces inflammation, may decrease consequences, decreases mortality more in adults vs. children

Question 37

Disadvantages of corticosteroid therapy in patient with meningitis

Answer 37

May decrease antibiotic penetration, no benefit if given after antibiotics

Question 38

When should corticosteroids be used relative to abx therapy?

Answer 38

10-20 minutes before

Question 39

Drug of choice and dosing for corticosteroid therapy adjunct to meningitis abx therapy

Answer 39

Dexamethasone 0.15 mg/kg q6h for 2-4 days

Question 40

When should corticosteroid therapy NOT be discontinued

Answer 40

growing H. influ or S. pneumoniae

Question 41

What severe adverse effect is associated with acyclovir for encephalitis?

Answer 41

Nephrotoxicity

Question 42

What treatment is given to treat encephalitis and how does dosing work?

Answer 42

Acyclovir, dose based on IBW and renal function

Question 43

What is the target organism / benefit of corticosteroids for adults?

Answer 43

Strep pneumo / mortality

Question 44

What is the target organism / benefit of corticosteroids for children?

Answer 44

H. influ / hearing loss