CSF Cultures

Question 1

Obj.1: Differentiate between acute, chronic and “aseptic” meningitis, encephalitis and meningoencephalitis

Question 2

Obj. 2: Recognize the most common cause of chronic meningitis

Question 3

Obj. 3: Recognize the most common cause of aseptic meningitis

Question 4

Obj. 4: Recognize the signs and symptoms of meningitis, including the Brudzinski and Kernig signs used for diagnosis

Question 5

Obj. 5: Recognize complications that may occur in patients with meningitis

Question 6

Obj.6: Describe the Brudzinski and Kernig signs

Question 7

Obj. 7: List the bacteria most commonly involved in acute bacterial meningitis relative to patient age
Newborns
Young children (immunized)
Young children (nonimmunized)
Young adults
Older adults

Answer 7

Newborns: Grp. B Strep, E. coli, Listeria
Young children (immunized): S. pneumo, N. meningitidis, GNRs
Young children (nonimmunized): Haemophilus influenze (type B)
Young adults: N. meningitidis, S. pneumo
Older adults: S. pneumo, S. aureus, Listeria, aerobic GNRs

Question 8

Obj. 8: List the most common bacteria involved in brain abscesses

Answer 8

Anaerobes (esp. mouth flora): S. intermedius, Fuso, Prevatella

Question 9

Obj. 9: List the most common bacteria involved in shunt infections

Answer 9

Coag neg staph, S. aureus, P. acnes, GNRs (E. coli, Kreb spp, Proteus spp.)

Question 10

Obj. 10: Recognize the CSF pathogens listed in Obj. 20 which have vaccinations available

Answer 10

H. influenza (Type B)
S. pneumo
N. meningitis

Question 11

Obj. 11: Differentiate between a subdural tap, ventricular aspiration and a lumbar puncture

Question 12

Obj. 12: Correlate collection tubes 1, 2 and 3 with the specific laboratory tests recommended (based on collection order)

Question 13

Obj. 13: Correlate typical lab findings for cell type, glucose and protein with the various types of meningitis (bacterial, tuberculosis, fungal and viral) as well as with normal CSF

Question 14

Obj. 14: Outline the correct methods for processing CSF specimens (media, centrifugation, holding of specimen if not processed immediately, etc.)

Question 15

Obj. 15: Recognize the media that is set up on all CSF cultures

Answer 15

BAP, CHOC, Thio (if from a brain abscess, include AnaBAP)

Question 16

Obj. 16: Outline the procedure that should be followed if a CSF direct smear is positive for bacteria

Question 17

Obj. 17: List additional tests which may be set up on GPCs in pairs directly from the CSF sample

Question 18

Obj. 18: Provide additional test(s) which can be performed if Gram stains are negative and many neutrophils are observed, suggesting a bacterial infection

Question 19

Obj. 19: Summarize the advantages and limitations of utilizing rapid molecular diagnostics (such as the BioFire ME Panel) for direction detection of pathogens from a CSF specimen.

Question 20

Obj. 20: Identify the most common acute bacterial pathogens from Gram-stained direct CSF smears

Answer 20

Escherichia coli

Question 21

Obj. 20: Identify the most common acute bacterial pathogens from Gram-stained direct CSF smears

Answer 21

Escherichia coli

Question 22

Obj. 20: Identify the most common acute bacterial pathogens from Gram-stained direct CSF smears

Answer 22

Haemophilus influenzae

Question 23

Obj. 20: Identify the most common acute bacterial pathogens from Gram-stained direct CSF smears

Answer 23

Haemophilus influenzae

Question 24

Obj. 20: Identify the most common acute bacterial pathogens from Gram-stained direct CSF smears

Answer 24

Neisseria meningitidis

Question 25

Obj. 20: Identify the most common acute bacterial pathogens from Gram-stained direct CSF smears

Answer 25

Neisseria meningitidis

Question 26

Obj. 20: Identify the most common acute bacterial pathogens from Gram-stained direct CSF smears

Answer 26

Streptococcus agalactiae

Question 27

Obj. 20: Identify the most common acute bacterial pathogens from Gram-stained direct CSF smears

Answer 27

Streptococcus pneumoniae

Question 28

Obj. 20: Identify the most common acute bacterial pathogens from Gram-stained direct CSF smears

Answer 28

Listeria monocytogenes

Question 29

Obj. 21: Recognize the routine CSF culture medium (media) on which each of the above pathogens will grow:
Escherichia coli
Haemophilus influenzae
Neisseria meningitidis
Streptococcus agalactiae
Streptococcus pneumoniae
Listeria monocytogenes

Question 30

Obj. 22: Correlate the above pathogen images with clinical scenarios
Escherichia coli
Haemophilus influenzae
Neisseria meningitidis
Streptococcus agalactiae
Streptococcus pneumoniae
Listeria monocytogenes

Question 31

Obj. 23: Correctly identify, using appropriate biochemical tests, the most common CSF pathogens. (E. coli, K. pneumoniae, Enterobacter spp., S. agalactiae, Listeria monocytogenes, H. influenzae, S. pneumoniae, N. meningitidis)

Obj. 24: Recommend biochemical tests which should be set up to identify the above CSF pathogens (Note: KIA series is sufficient for Enterobacteriaceae.)

Answer 31

E. coli, K. pneumoniae, Enterobacter spp.: See Enterobacteriaceae flowsheet
S. agalactiae: Carrot/LIM broth
Listeria monocytogenes: Calatase +, Umbrella motitlity at 25, Bile Esculin +, Salicin +
H. influenzae: X & V determination, SBA Hemolysis (Serotyping for capsule)
S. pneumoniae: Bile solubility +, Optochin S, Quelling +
N. meningitidis: Rapid sugars: Glucose, Maltose +, ONPG =