Exam B

Question 1

lysis centrifugation is used for…

Answer 1

Dealing with intracellular organisms or contaminated broths?

Question 2

If a bacteria has mecA gene what would the antibiotic of choice be?

Answer 2

?

Question 3

Antibiotics that are synergistic →

Answer 3

beta lactams + aminoglycosides

Question 4

Recurrent fever →

Answer 4

Borrelia recurrentis

Question 5

Which entero is pos for arginine?***

Question 6

CIN bullseye colonies

Answer 6

Yersinia enterocolitica

Question 7

OF results (if orgs use glucose etc.)

If both yellow →

Answer 7

fermentation
ex: Escherichia coli

Question 8

OF result:

If open yellow and covered green →

Answer 8

oxidative
-Pseudomonas aeruginosa (nonfermenter)

Question 9

Of result:

If both green →

Answer 9

non-saccharolytic

Question 10

Which enterobacteria are positive for arginine?

Answer 10

-E. coli
-Entercoccus spp.
-Enterbacter spp.
-Mycobacterium hominis
-salmonella (triple pos)

Question 11

CIN bullseye colonies is seen with…

Answer 11

Yersinia enterocolitica

Question 12

What reagents are used for the nitrate test?

Answer 12

-reacts with sulfanilic acid (reagent A) and α-naphthylamine (reagent B)
and zinc dust (reagent C) if negative the first time.
-Reagent A + B = positive red color change
-Reagent A + B = negative no color change add Reagent C
-If no color change in Reagent C = positive

Question 13

ONPG pos is what color?
Turns this color in the presence of?

Answer 13

Yellow

β-GALACTOSIDASE

Question 14

how is chlamydia pneumoniae transmitted?

Answer 14

by coughing or sneezing, which creates small respiratory droplets that contain the bacteria.

Question 15

Characteristics of stentotrophomonas maltophilia include:

Answer 15

a. Oxidase maltose, DNase positive, non-motile
b. Motile and oxidase negative (Possibly)
c. Motile; oxidase positive, oxidizes maltose (usually oxidase negative, but can be up to 20% positive)
d. Oxidase negative and no growth on macconkey

Question 16

pseudomonas aeruginosa produces …

Answer 16

pyocyanin

Question 17

resin bottles stop the effects of…

Answer 17

antibiotics/meds

Question 18

Gram - rod isolated from wound infection that ferments lactose, produces acid slant and butt on TSI, oxidase +?

A. hydrophilia (Aeromonas hydrophilia) (Non-fermenter of lactose)

b. Campylobacter fetus (C. fetus)

C. V. cholera
(Considered a late lactose fermenter)

d. Campylobacter coli (C. coli)

Answer 18

C

Question 19

Stenotrophomonas are oxidase ________ and motile _________

Answer 19

negative

positive

Question 20

Stenotrophomonas oxidation?

Answer 20

glucose oxidizer (check this one)

Question 21

Pseudomonas are positive for…

Answer 21

motility, glucose oxidizer, and oxidase.

Question 22

Gram - rod, non glucose fermenter, that produces H2S found on wound?

Answer 22

?

Question 23

What level of CO2 should CO2 incubators be at?

Answer 23

5-10%

Question 24

Gram - bacilli, nitrate +, indole -, citrate +, MR +, urease -, H2S positive?

Answer 24

S. enteritidis

(distinguishing factor is H2S positive)

Question 25

All species of Salmonella is citrate positive except __________

Answer 25

typhi

Question 26

Salmonella paratyphi is H2S ________.

Answer 26

negative

Question 27

E. coli is indole _________.

Answer 27

positive

Question 28

E. sonneri is indole ___________.

Answer 28

positive

Question 29

Aeromonas characteristics and lab results?

Answer 29

?

Question 30

shewanella characteristics and lab results?

Answer 30

?

Question 31

What does the MIC tell you?

Answer 31

determines the lowest concentration of an antimicrobial agent that can effectively inhibit the growth of a specific microorganism

Question 32

MIC broth dilution

Answer 32

-

Question 33

which bacteria has brick red fluorescence?

Answer 33

Prevotella and Porphyromonas

Question 34

What organism is susceptible for SPS disc?

Answer 34

P. anaerobius

Question 35

Differ between M.hominis and U.urelyticus?

Answer 35

M. hominis → small pinpoint colonies, (arginine positive) U.urelyticus → urease +, large fried egg colonies,

Question 36

If your RPR test is positive...

Answer 36

you will need more tests to confirm that you have syphilis → not specific enough

Question 37

D-test is looking for...

Answer 37

inducible clindamycin resistance due to erythromycin being there

Question 38

all the organisms that are H2S positive

Answer 38

Citrobacter (only lactose fermenter) Salmonella (- urease) Proteus (+ urease)

Question 39

Urease positive organisms

Answer 39

Proteus Klebsiella Serratia Moranella ‘Mnemonic – Uncle Pete Knitted Sweaters on Monday’

Question 40

Citrobacter is urease...

Answer 40

variable

Question 41

organisms that present as bipolar rods (safety pin) Which shows bipolar staining

Answer 41

B. fragilis has safety pin appearance due to vacuoles Yersinia (pestis) show bipolar staining

Question 42

Yersinia enterocolitica has a _____________ appearance on CIN agar

Answer 42

bull's eye

Question 43

the full name of the lysine decarboxylase

Answer 43

LYSINE IRON AGAR

Question 44

lysine decarboxylase test: Full purple →

Answer 44

lysine decarboxylase***

Question 45

lysine decarboxylase test: Purple slant, yellow butt →

Answer 45

glucose fermentation

Question 46

lysine decarboxylase test: Yellow butt, red slant →

Answer 46

deamination of lysine Proteus and Providencia

Question 47

The Adv and Disadv to the broth dilution AST?

Answer 47

-

Question 48

An incoulum on a Muller Hinton Kirby Bauer broth is equivalent to 2 MacFarland Standard. Which is true? a. Zone is too large b. Zone is too small c. Zone is correct d. Needs longer incubation

Answer 48

?

Question 49

Bread crumb colonies...

Answer 49

Fusobacterium nucleatum (yellow)***

Question 50

Black pigmented colony...

Answer 50

eptococcus niger → also Prevotella/Porphyromonas (have pigment)***

Question 51

Pitted agar...

Answer 51

Eikenella corrodens

Question 52

Brick red fluorescence...

Answer 52

Prevotella and Porphyromonas***

Question 53

Ground glass colonies...

Answer 53

C. difficile (yellow ground glass colonial morphology)

Question 54

“Molar tooth colony”

Answer 54

Actinomyces (older colonies)

Question 55

“Sulfur granules”

Answer 55

Actinomyces

Question 56

a man with dysuria and discharge coming out of his penis → discharge had WBCs but no bacteria caused by...

Answer 56

Lymphogranuloma venereum

Question 57

QC using Klebsiella oxytoca on an API strip test, shows all positive results except VP. What is the best course of action? a. Return the api test b. reagent strips back to the manufacturer Make new VP reagents and retest c. Streak a new isolate of Klebsiella and retest d. Report to supervisor about…

Answer 57

c. Streak a new isolate of Klebsiella and retest

Question 58

How machines can tell if there is a pos blood culture or not?

Answer 58

-Turbidity -color change, gas production, and colony formation -Blood culture machines determine a positive by the change in CO2***

Question 59

Anaerobic gram negative bacteria was detected from a neck abscess. The colonies looked like bread crumbs. What are the expected biochemical test results?

Answer 59

Susceptible to Kanamycin and colistin

Question 60

What two organisms are resistant to all 3 antibiotic discs?

Answer 60

B. fragilis and Prevotella***

Question 61

Prevotella is Bile Esculin ______.

Answer 61

negative

Question 62

B. fragilis is bile esculin _______.

Answer 62

positive

Question 63

Blood cultures: only report bacteria that grow on BOTH bottles. If they only grow in one, they are most likely...

Answer 63

contaminants

Question 64

Patient came in with a wound with dark pigment to it, what would the bacteria be?

Answer 64

?

Question 65

Fusobacterium nucleatum?

Answer 65

?

Question 66

Bacteria that has “pointed ends”

Answer 66

?

Question 67

-In the GI tract -Some members are indigenous microflora and can be opportunistic pathogens -There are other bacilli in the GI tract that are NOT apart of this family -Associated with various human diseases (Abscesses, GI tract infections, Meningitis, Pneumonia, Septicemia, UTIs, Wound infections)

Answer 67

Enterobacteriaceae family -Extra intestinal infections (occur outside the GI tract) – UTIs, respiratory infections, wound infections, bloodstream infections, and CNS infections

Question 68

Is salmonella and Shigella indigenous microflora?

Answer 68

NO! ALWAYS PATHOGENIC

Question 69

MOST COMMON causes of nosocomial infections

Answer 69

Enterobacteriaceae

Question 70

MOST GI tract infections are caused by:

Answer 70

Escherichia Salmonella Shigella Yersinia

Question 71

Enterobacteriaceae: NON MOTILE members include...

Answer 71

-Klebsiella -Shigella

Question 72

Enterobacteriaceae: ___________ fermenters.

Answer 72

glucose***

Question 73

Enterobacteriaceae: facultative _________.

Answer 73

anaerobes

Question 74

True or false Enterobacteriaceae are spore forming

Answer 74

false. Non-spore forming.

Question 75

Enterobacteriaceae: Catalase ___________.

Answer 75

positive – except Shigella dysenteriae

Question 76

Enterobacteriaceae: Oxidase __________.

Answer 76

negative – except Plesiomonas shigelloides.

Question 77

True or false: Enterobacteriaceae capable of reducing nitrate to nitrite

Answer 77

true

Question 78

Enterobacteriaceae: capable of growing on ___________ agar.

Answer 78

MacConkey

Question 79

Enterobacteriaceae: Most members of the family are motile by _________ flagella.

Answer 79

peritrichous

Question 80

Lactose Fermenters...

Answer 80

E. coli Klebsiella Pantoea Enterobacter Citrobacter Serratia

Question 81

Non-Lactose Fermenting...

Answer 81

Salmonella Shigella Proteus Morganella morganii Providencia Yersinia

Question 82

Non-lactose fermenters, motile, and produces H2S

Answer 82

Proteus salmonella

Question 83

Non-lactose fermenters, nonmotile, non-H2S producers

Answer 83

Shigella yersina

Question 84

Enterobacteriaceae Antigens. O=

Answer 84

outer membrane

Question 85

Enterobacteriaceae Antigens.: H=

Answer 85

Flagella

Question 86

Enterobacteriaceae Antigens.: K=

Answer 86

capsule

Question 87

Enterobacteriaceae Antigens.: VI=

Answer 87

capsule of salmonella

Question 88

What bacteria have swarming effect?

Answer 88

Proteus Swarming effect – P. mirabilis & P. vulgaris