CNS

Question 1

normal volume of CNS

Answer 1

90-150 ml

Question 2

normal protein level in CSF

Answer 2

15-45 mg/L

Question 3

normal CSF glucose level

Answer 3

40-80 mg/L

Question 4

normal WBC differential in adult

Answer 4

60-80% Lymph
10-40% Mono
0-15% Neuts

Question 5

infection of CSF is usually associated with increased_____ _______ and a change in the amount of ________&_________

Answer 5

WBC
protein;glucose

Question 6

a semi-permeable membrane that separates brain tissue from blood; it protects brain from toxins, pathogens while letting nutrients in

Answer 6

Blood Brain Barrier

Question 7

a functional barrier found in the choroid plexus of the brain ventricles; separates blood from CSF& the CSF from the brain

Answer 7

Blood CSF Barrier

Question 8

infiltration of the BBB by a microorganism

Answer 8

Encephalitis

Question 9

infiltration of the BCB by a microorganism; can also be caused by injury, cancer, and some drugs; causes inflammation of the CSF and meninges; A MEDICAL EMERGENCY

Answer 9

Meningitis

Question 10

organism gets into bloodstream from nearby infection in another part of the body (often a respi infection)

Answer 10

Hematogenous spread

Question 11

organism colonizing a nearby body site like nasal or sinus mucosa gets directly into CSF; usually after a viral infection of nasal passage or sinus

Answer 11

Direct Contiguous spread

Question 12

bacteria get in directly from an open wound due to a cranial injury or from cranial surgery

Answer 12

Direct spread via cranial trauma or surgery

Question 13

Bacteria commonly causing meningitis by age group:
neonates <1 month

Answer 13

GNB
GBS
Listeria monocytogenes

Question 14

Bacteria commonly causing meningitis by age group:
Infants 1 month- 23 months

Answer 14

GBS
E coli
Neisseria meningitidis
Strep pneumo
Haemophilus Influenzae type B

Question 15

Bacteria commonly causing meningitis by age group:
Children and adults

Answer 15

Neisseria meningitidis
Streptococcus pneumoniae
Cryptococcua neoformans- adults with HIV

Question 16

Bacteria commonly causing meningitis by age group:
Older Aldults > 65yrs

Answer 16

Neisseria meningitidis
Strep pneumo
Cryptococcus neoformans
GNB
Listeria monocytogenes

Question 17

this group of organisms rarely cause meningitis; when they do, it’s usually because person had/has a brain abscess & organisms spread to CSF

Answer 17

anaerobes

Question 18

this organism causes serious infection during pregnancy- ingested in contaminated food (dairy, lunchmeat, poorly washed raw veg)
- can invade cells and survive intracellularly (moves from cell to cell using actin filaments) which allows it to enter mom’s blood and cross the placental barrier

Answer 18

Listeria

Question 19

a listeria meningitis in newborn < 7 days; from intrauterine infection or during birth, causes sepsis and to a lesser extent meningitis- high mortality rate if 50%

Answer 19

Early Onset

Question 20

Listeria meningitis in newborn >7 days; infection after birth from mom or another source- manifest as meningitis; more rare and has a lower fatality rate

Answer 20

Late onset

Question 21

this organism colonize adult intestine& genital tract in women; causes more serious infection in pregnancy, babies & elderly; can infect the amniotic fluid & baby leading to premature rupture of membranes & still birth

Answer 21

GBS

Question 22

when is GBS screening done on all pregnant women? specimen type?

Answer 22

35-37 weeks gestation
vaginal/rectal swab

Question 23

GBS meningitis in newborn (prenatal & < 7 days old); baby aspirates amniotic fluid during birth; causes PNEUMONIAE OR SEPSIS and sometime meningitis- high mortality

Answer 23

Early onset

Question 24

GBS meningitis in Newborn (at least 7 days old); baby infected by mom or from the other source after birth; causes mostly meningitis, sometime septicemia or pneumonia- mortality rate is lower

Answer 24

Late Onset

Question 25

GBS gram: Catalase: Bile esculin motility at 25 Hippurate hydrolysis Camp:

Answer 25

gpc in p&c neg neg neg pos pos (arrowhead)

Question 26

Listeria gram Catalase Bile esculin Motility at 25 Hippurate hydrolysis Camp

Answer 26

small gpb pos pos pos (umbrella motility) Pos pos (rectangle)

Question 27

vaccine for infants and young children

Answer 27

HIB conjugate vaccine 13 valent conjugate pneumococcal vaccine

Question 28

vaccine for > 2 yrs old and those at high risk

Answer 28

23- valent polysaccharide pneumococcal vaccine

Question 29

vaccine for all healthy adolescents 11 or 12 yrs of age and 2-55 years old people who are at risk such as travelers to endemic areas, asplenic patients

Answer 29

Quadrivalent conjugated meningococcal vaccine

Question 30

vaccine for > 55 yr

Answer 30

meningococcal polysaccharide vaccine

Question 31

inflammation/infection of the brain; caused by invasion of an organism (most often due to a virus) but can also be bacteria, fungus or parasite

Answer 31

infectious encephalitis

Question 32

inflammation of the brain due to an autoimmune response, tumour

Answer 32

Non-infectious encephalitis

Question 33

a pus-filled pocket of infected material in the brain; usually occurs when a bacteria or fungus enter the brain; IV drug users are also at risk often polymicrobial infection that includes anaerobes result in brain swelling with harmful pressure on brain tissue

Answer 33

Brain Abscess

Question 34

diagnosis of CNS infections is based on examinations of ______ &_________ __________

Answer 34

CSF Blood cultures

Question 35

______ is obtained by inserting a sterile hollow needle into the subarachnoid space of the lower lumbar

Answer 35

CSF

Question 36

specimen for brain abscess

Answer 36

tissue biopsy or aspirates because CSF may be normal

Question 37

All CNS specimens are sterile. must be transported to the lab ASAP- must be plated to a media within __ hour; if delay <24 hrs, keep at_____ ______

Answer 37

1 room temperature

Question 38

where is the thin needle for lumbar puncture inserted during CSF collection

Answer 38

lumbar subarachnoid space

Question 39

CSF specimen collection: collect 3-4 tubes- each containing _ to _ ml; microbiology gets the tube that is least likely to have contamination ( tube __ or ___) for culture & AST; tube __ is sent to Chemistry; tube _ or _ is sent to Haematology for cell counts

Answer 39

1-2 2 or 3 1 3 or 4

Question 40

if only one tube is collected, it MUST go to ______ lab first to ensure sterility of culture

Answer 40

Microbiology

Question 41

a sign of bacterial meningitis, a high WBC count, presence of protein or lysed RBC

Answer 41

Cloudy CSF

Question 42

indicates presence of bilirubin & is sometime the only sign of an acute subarachnoid hemorrhage

Answer 42

Xanthochromia(yellow discoloration)

Question 43

a subarachnoid bleed or traumatic tap

Answer 43

Bloody and cloudy CSF