B6-088 Gangrene

Question 1

catalase positive cocci in clusters

Answer 1

staphylococcus

Question 2

beta hemolytic cocci in chains

Answer 2

S. pyogenes (GAS)
S. agalactiae (GBS)

Question 3

anaerobic gram positive bacilli [3]

Answer 3

clostridium
actinomyces
propionibacterium

Question 4

anaerobic gram negative bacilli [4]

Answer 4

bacteriodes
fusobacterium
prevotella
prophyromonas

Question 5

GAS diseases of skin [3]

Answer 5

impetigo
erysipelas/cellulitis
necrotizing fasciitis

Question 6

systemic diseases caused by GAS [4]

Answer 6

bacteremia
rheumatic fever
acute glomerulonephritis
streptococcal TSS

Question 7

raised, bright red plaques with sharply defined borders

Answer 7

erysipelas

Question 8

allows typing of GAS into different strains

Answer 8

M protein

Question 9

what virulence factor of GAS helps the bacteria to “hide” from immune system?

Answer 9

hyaluronic acid capsule

Question 10

toxin that causes GAS to form a superantigen (causes Scarlet fever and TSS)

Answer 10

Spe

Streptococcus pyrogenic exotoxin

Question 11

GAS virulence factor that helps the bacteria spread in tissues
can sometimes be inactivated or mutated

Answer 11

hyaluronidase

Question 12

GAS virulence factor that activates plasminogen to dissolve clots

Answer 12

streptokinase

Question 13

DOC for cellulitis caused by GAS [2]

Answer 13

penicillin, ceftriaxone

Question 14

DOC for TSS caused by GAS

Answer 14

penicillin + clindamycin

to suppress toxin production via 50S ribosome inhibition

Question 15

cause 80% of skin/soft tissue infections
causes septic shock with high mortality

Answer 15

staphylococcus

Question 16

SSSS is caused by toxins […] and […]

Answer 16

ETA and ETB

Question 17

sudden fever followed by headache, sore throat, diffuse red rash and skin desquamation
can progress to shock within 48 hrs

Answer 17

TSS (staphy)

Question 18

opsonizes bacteria and enhances phagocytosis

Answer 18

C3b

Question 19

catalase +
coagulase +
beta hemolytic
mannitol fermentation +

Answer 19

S. aureus

Question 20

catalase +
coagulase -
ALP +
urease +
novobiocin susceptible

Answer 20

S. epidermis

Question 21

catalase +
coagulase -
ALP -
urease +
novobiocin resistant

Answer 21

S. saprophyticus

Question 22

exogenous anaerobe
spore former

Answer 22

clostridium

Question 23

places of heavy bacterial flora [2]

Answer 23

gingival crevice
colon

Question 24

aerobes or facultative anaerobes can colonize and deplete the oxygen, providing and opportunity for […] to colonize

Answer 24

anaerobes

Question 25

foul odor sulfur granules necrosis/abscess previous antibiotic therapy are all clues for [..]

Answer 25

anaerobic infection

Question 26

most common anaerobe isolated from human infection

Answer 26

B. fragilis

Question 27

bile resistant bile-esculin agaar

Answer 27

B. fragilis

Question 28

2nd most common anaerobic bacteria causing infections normally cause orofacial and pleuropulmonary infections [2]

Answer 28

prevotella prophyromonas

Question 29

how to distinguish between prevotella and prophyromonas?

Answer 29

prevotella is saccharolytic (glucose fermentor) prophyromonas is asaccharolytic

Question 30

bacteriodes is penicillin [...]

Answer 30

resistant

Question 31

prophyromonas is vancomycin [...]

Answer 31

sensitive

Question 32

prevotella is vancomycin [...]

Answer 32

resistant

Question 33

[prevotella or prophyromonas] growth on KV BAP

Answer 33

prevotella is vanc resistant

Question 34

[prevotella or prophyromonas] no growth on KV BAP

Answer 34

prophyromonas

Question 35

DOC for gram-negative anaerobes [2]

Answer 35

metronidazole carbapenem

Question 36

DOC for P. acnes

Answer 36

benzoyl peroxide/erythromycin

Question 37

causes "lumpy jaw" abscesses

Answer 37

actinomycosis

Question 38

forms abscesses with sulfur granules forms molar tooth colonies

Answer 38

actinomycosis

Question 39

treatment for actinomycosis

Answer 39

debridement + penicillin

Question 40

part of a group of bacteria that causes displacement of normal bacterial flora fishy odor on Whiff test clue cells

Answer 40

mobiluncus

Question 41

causes botulism

Answer 41

C. botulinum

Question 42

causes pseudomembranous colitis

Answer 42

C. difficle

Question 43

causes gas gangrene

Answer 43

C. perfringens

Question 44

causes tetanus

Answer 44

C. tetani

Question 45

major toxins of C. botulinum

Answer 45

A, B, E, F

Question 46

major toxin of C. perfringens causing gas gangrene

Answer 46

alpha toxin

Question 47

major toxin of C. tetani

Answer 47

tetanospasmin

Question 48

inhibits nerve impulses causing flaccid paralysis

Answer 48

C. botulinum toxin

Question 49

resistant to penicillin and associated with intraabdominal abscesses

Answer 49

bacteriodes

Question 50

gram-negative VancR ferment glucose sensitive to penicillin

Answer 50

prevotella

Question 51

how does the presence of bacteriodes support the growth of penicillin susceptible bacteria?

Answer 51

bacteriodes secretes beta-lacatamase **need a beta-lactamase inhibitor like amoxicillin-clavulanate

Question 52

gram negative and grows in pairs (diplococcus)

Answer 52

N. gonorrhoeae

Question 53

TSS is caused by

Answer 53

TSST-1 (superantigen)

Question 54

main toxin of C. perfringens

Answer 54

alpha-toxin does phospholipid hydrolysis causing cell lysis and tissue destruction

Question 55

SNAP-25 is affected by [...] toxin

Answer 55

botulinum toxin

Question 56

VAMP is affected by [...] toxin

Answer 56

tetanus

Question 57

what organ systems does nocardiosis affect?

Answer 57

skin lungs central nervous system