Microbiology Of Cns

Front 1

How do most microorganisms get to CNS?

Back 1

Through blood

Front 2

Name 3 mechanisms of meningitis

Back 2

- Infect cells lining barrier

- Passively transported across barrier in vacuoles

- Carried across barrier in infected leukocytes

Front 3

Organisms causing meningitis in neonates

Back 3

Strep B - Strep. agalactiae

E.coli

Listeria monocytogenes

Front 4

Organisms causing meningitis in infants and children

Back 4

S. pneumoniae

N. meningitidis

H. influenzae

Front 5

What is the most important virulence factor of organisms causing acute meningitis?

Back 5

CAPSULE - antiphagocytic, allows to escape immune system

Front 6

What are the symptoms of clinical infant meningitis

Back 6

Nuchal rigidity, opisthotonos, bulging fontanelle, convulsions, photophobia, lethargy, irritability, seizures, coma

Front 7

What are the cardinal signs of meningitis

Back 7

Fever

Nuchal rigidity

Vomitting

Front 8

What are two physical signs that could be performed and are indicative of presence of meningitis

Back 8

Kernigs sign + Brudzinskis sign

Front 9

If patient has maculopapular or petechial rash with the signs of meningitis, it is indicative of what type of meningitis

Back 9

Meningococcal

Front 10

Shape + Stain STREP PNEUMONIAE

Back 10

Gram positive diplococci

Front 11

Pneumococcal meningitis usually follows _

Back 11

Bacteremia, sinusitis or otitis media

Front 12

Which patients are in higher risk of pneumococcal meningitis

Back 12

Sickle cell patients

Patients with asplenia

Elderly

Front 13

Are cardinal signs of meningitis present in pneumococcal meningitis

Back 13

YES

Front 14

How do you diagnose pneumococcal meningitis

Back 14

Culture (CSF and blood) + Gram stain CSF

INCREASED NEUTROPHILS IN CSF, BACTERIA PRESENT IN CSF

Front 15

What is the best treatment for pneumococcal meningitis

Back 15

Third generation cephalosporins

Front 16

Which drugs for treatment of pneumococcal meningitis is contraindicated in children

Back 16

FLuoroquinolones

Front 17

Name vaccine against pneumococcal meningitis

Back 17

Heptavalent pneumococcal vaccine - 2-23 months + for older children at high risk 2-5 years old

After 5 years old - 23 valent vaccine

Front 18

NEISSERIA MENINGITIDIS

Shape + Stain

Back 18

Gram negative diplococcus

Front 19

Which serotype of Neisseria Meningitidis is responsible for meningitis epidemics in developing countries

Back 19

A

Front 20

Which serotypes of N. meningitidis are common in US

Back 20

B, C, Y and W-135

Front 21

20% of population are carriers of N. meningitidis - where is it located?

Back 21

Attached to epithelial cells in nasopharynx

Front 22

Epidemics of meningitis in overcrowded areas - schools, military bases, prisons are caused by which organism?

Back 22

N. meningitidis

Front 23

How do you diagnose meningococcal meningitis

Back 23

Primarily by clinical signs - also culture CSF and blood, Gram stain of CSF, increased WBC count in CSF

Front 24

What is a treatment of meningococcal meningitis

Back 24

Penicillin or ampicillin, chloramphenicol - after acute infection 1 dose rifampin

Front 25

As chemoprophylaxis for family members of patient with meningococcal meningitis - what drug is used and why

Back 25

Rifampin - clears nasopharyngeal carriages (penicillin does not)

Front 26

What is preferred vaccine for N. meningitidis for 2-10 year olds and over 55 year old

Back 26

Meningococcal polysaccharide vaccine (MPSV4 or Menomune)

Front 27

What is preferred vaccine for N. meningitidis in people 11-55 year old + people at high risk (college freshmen, military recruits, etc)

Back 27

Meningococcal conjugate vaccine (MCV4 or Menactra)

Front 28

Which serotype of N. meningitidis is NOT included in the vaccine and is most commonly seen in US

Back 28

B

Front 29

H. INFLUENZAE B - shape + stain

Back 29

Gram negative pleomorphic coccobacilli

Front 30

Which organism used to be primary cause of pediatric meningitis but now only seen in unvaccinated children

Back 30

H. influenzae

Front 31

How long do maternal antibodies protect infant from H. influenzae

Back 31

3-4 months

Front 32

Meningitis caused by H. influenzae usually follows _

Back 32

Upper respiratory infection followed by fever and severe headache

Front 33

What are the sequelae of meningitis caused by H. influenzae

Back 33

Hearing loss
Retardation
Seizures

Front 34

H. influenzae does NOT grow on which medium

Back 34

MacKonkeys or Blood agar

Front 35

What two factors does H. influenzae need for growth

Back 35

X (hemin) and V (NAD) factors

Front 36

H. parainfluenzae only needs one factor -

Back 36

V factor

Front 37

H. influenzae can only be cultured on which medium

Back 37

Chocolate agar

Front 38

How do you treat meningitis caused by H. influenzae

Back 38

Broad spectrum cephalosporins

Front 39

Serratia, Pseudomonas, Proteus are NOT common causes of neonatal meningitis but occur in _

Back 39

Premature infants -respiratory equipment

Front 40

Are cardinal signs of meningitis present in neonatal meningitis

Back 40

NO

Front 41

Which serotype of Group B strep causes most cases of meningitis

Back 41

III

Front 42

LISTERIA MONOCYTOGENES - shape + stain

Back 42

Gram positive rods

Front 43

Which organism grows on most media in cold selection (4 degrees C)

Back 43

Listeria monocytogenes

Front 44

C. BOTULINUM and C. TETANI - Shape + Stain

Back 44

Gram positive rods, anaerobic, spore forming

Front 45

Botulinum toxin causes what in infants?

Back 45

Flaccid paralysis

Front 46

MOA botulinum neurotoxin

Back 46

Inhibits release of Ach

Front 47

How would infant suffering from botulism present

Back 47

Failure to thrive

Constipation

Flaccid paralysis

Front 48

MOA tetanus toxin

Back 48

Prevents release of inhibitory NT

Front 49

What do you see in 75% of patients with tetanus

Back 49

Strismus - lock jaw

Front 50

What is appropriate treatment of tetanus

Back 50

Antimicrobial therapy first followed by tetanus immunoglobulin

Front 51

What distinguishes Brucella bacteria

Back 51

INTRACELLULAR