May1 M3-CNS Infections

Question 1

classification of meningitis

Answer 1

• bacterial (community acquired OR healthcare-associated/post-neurosurgical)
• viral
• fungal
• mycobacterial
• parasitic

Question 2

(imp?) most common bacterial pathogen for meningitis in neonates IN THE COMMUNITY (<1 month of age)

Answer 2

GEL

• 1. GBS (agalactiae), transmitted vertically intrapartum*
• enterobacteriaceae
• listeria (rare now)

Question 3

(imp?) most common bacterial pathogen for meningitis in 1-23 months old babies (>1, <24) IN THE COMMUNITY

Answer 3

strep pneumoniae

Question 4

(imp?) most common bacterial pathogen for meningitis in 2-50 year old people IN THE COMMUNITY

Answer 4

strep pneumo (also Neisseria)

Question 5

(imp?) most common bacterial pathogen for meningitis in people over 50 years of age

Answer 5

• 1. strep pneumo *
     
     2. Neisseria
     3. Listeria* (comes back)

Question 6

pathogen with important mortality in meningitis

Answer 6

Neisseria meningitidis

Question 7

who’s especially susceptible for Neisseria meningitidis infections

Answer 7

C5-C9 (MAC) complement deficiencies patients. vulnerable to encapsulated organisms in general (S pneumo, N mening, haemophilus influenza)

Question 8

classical organisms that are encapsulated

Answer 8

• Strep pneumo
• N mening
• Haemophilus influenza

Question 9

(important) spleen removed = at risk for what infections (what type of meningitis) #1 and #2

Answer 9

encapsulated organisms

• strep pneumo (#1)
• neisseria meningitidis (#2)
• haemophilus influenza

Question 10

(important) how bacterial meningitis organisms are transmitted

Answer 10

by droplets

Question 11

how do you get listeria monocytogenes infection (and meningitis)

Answer 11

from contaminated foods

Question 12

(imp?) conditions that increase risk of listeriosis (listeria infection and meningitis)

Answer 12

• iron overload conditions (like hemochromatosis)

- immunodeficiency conditions (neonates, old, pregnant, etc.)

Question 13

(imp?) listeriosis affects what group especially

Answer 13

pregnant women because of immunodeficiency

Question 14

pathogens in HOSPITAL associated bacterial meningitis

Answer 14

• aerobic gram- bacilli like pseudomonas is 40% of cases
• staph aureus and CoNS (epidermidis, etc.)
• propionibacterium acnes (on plastic devices)

Question 15

what viruses cause the majority of viral meningitis

Answer 15

enteroviruses (echoviruses, coxsackie viruses)

Question 16

signs of meningitis in children

Answer 16

• fever
• poor feeding
• vomiting
• irritability

Question 17

signs of meningitis in adults

Answer 17

headache, fever, meningismus = mucorigidity, altered mental status + Brudzinki’s sign, Kernig’s sign, Jolt accentuation

Question 18

skin manifestations in meningitis

Answer 18

-purpura fulminans (hemorrhagic necrotic bullae) = Neisseria meningitidis (and also Strep pneumo and enterovirus)

Question 19

bacterial vs viral meningitis

Answer 19

• opening P in CSF: B = 200-500. viral = normal, max 200
• WBC >1000 = B
• PMNs > 80% = B
• protein > 1g/L = B
• positive gram stain=B

Question 20

(imp?) neonatal (0-1 mo) bacterial meningitis: Abx given and organisms covered

Answer 20

ampicillin IV + cefotaxime (3rd gen cephalo) IV

GBS, gram- enteric rods, listeria

Question 21

(imp?) infant (1-3 mo) bacterial meningitis: Abx given and organisms covered

Answer 21

ampicillin IV + (Cefotaxime or Ceftriaxone IV) + Vancomycin IV
(GBS, gram- enteric rods, listeria, S. pneumo)

Question 22

(imp?) 3 months to 50 yrs of age bacterial meningitis: Abx given and organisms covered

Answer 22

(Cefotaxime or Ceftriaxone IV) + Vancomycin IV

S. pneumo, N mening, H infl type B

Question 23

(imp?) 50 years+ and immunocompromised bacterial meningitis: Abx given and organisms covered

Answer 23

ampicillin IV + (ceftriaxone or cefotaxime IV) + Vancomycin IV
(S pneumo, N mening, listeria)

Question 24

(imp?) healthcare associated bacterial meningitis: Abx given and organisms covered

Answer 24

-Vanco + (ceftazidime or cefepime or meropenem)

(cover gram- rods like pseudomonas, CoNS and staph aureus

Question 25

(imp?) Abx for S pneumo OR N meningitis OR H infl meningitis susceptible to penicillin

Answer 25

penicillin G or ampicillin (for H infl, only ampicillin) (cross BBB)

Question 26

(imp?) Abx for S pneumo OR N meningitidis OR H infl meningitis resistant to penicillin

Answer 26

Cefotaxime or Ceftriaxone IV (cross BBB)

Question 27

(imp?) Abx for GBS or listeria meningitis

Answer 27

beta-lactam IV + aminoglycoside IV

Question 28

adjunctive therapy to the Abx that is given in certain conditions in meningitis and when

Answer 28

``` adjunctive steroids (IV dexamethasone) for H infl meningitis in all ages and S pneumo meningitis in adults (decrease neuro damage *hearing loss* and cytokine influx) ```

Question 29

encephalitis def

Answer 29

inflam process of brain parenchyma associated with lab or clinical evidence of brain dysfunction

Question 30

usual causes of encephalitis and list some examples

Answer 30

viruses (HSV-1 most common, rabies, nipah, LCV, SLE, WNF, JEF, etc.)

Question 31

(important) most common cause (specifically) of viral encephalitis

Answer 31

HSV-1

Question 32

bacterial vs viral differentiation in meningitis vs encephalitis

Answer 32

CSF analysis can help make the difference in meningitis but not in encephalitis (CSF is same in viral vs bacterial encephalitis)

Question 33

(imp?) tx of encephalitis

Answer 33

- no therapy except for herpes | - herpes: acyclovir IV for 21 days, check kidneys and baseline renal fct

Question 34

(imp?) important principle in HSV encephalitis treatment

Answer 34

start to treat early: results in significantly decreased morbidity and mortality

Question 35

(imp?) classic triad of bacterial meningitis

Answer 35

- fever - headache (that is worse with light) - nuchal rigidity

Question 36

investigation step that is done for every patient with encephalitis

Answer 36

send CSF for HSV and enterovirus PCR for every patient

Question 37

considerations of cause of encephalitis in immunocompromised patient

Answer 37

think of the following herpesviruses: EBV, CMV, VZV, HHV-6