Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Bacte Lec [Finals] > RATIONALE FINALS > Flashcards

RATIONALE FINALS Flashcards

1
Q

Biochemically, the Enterobacteriaceae are gram-negative rods that:
A. Ferment glucose, reduce nitrate to nitrite, and are oxidase negative
B. Ferment glucose, produce indophenol oxidase, and form gas
C. Ferment lactose and reduce nitrite to nitrogen gas
D. Ferment lactose and produce indophenol oxidase

A

A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Which genera of the Enterobacteriaceae are known to cause diarrhea and are considered enteric
pathogens?
A. Enterobacter, Klebsiella, Providencia, and Proteus
B. Escherichia, Salmonella, Shigella, and Yersinia
C. Pseudomonas, Moraxella, Acinetobacter, and Aeromonas
D. Enterobacter, Citrobacter, and Morganella

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

MacConkey agar: little normal flora with many non-lactose-fermenting colonies
Hektoen enteric agar: many blue-green colonies
Campylobacter blood agar and C. difficile agar: No growth
Oxidase: colorless Indole: yellow
Urease: orange SIM: no brush-like appearance, no blackening
ONPG: colorless
The most likely identification is:

a. Shigella dysenteriae
b. Salmonella gallinarum
c. Shigella flexneri
d. Escherichia coli

A

A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

A wound aspirate culture from a nursing home patient grew gram-negative rods on MacConkey
agar as pink to dark pink oxidase-negative colonies. Given the following results, which is the most
likely organism?
TSI = A/A
VP = red
Urease = magenta
Indole = yellow
Citrate = blue
MR = yellow
H2S = No blackening
Antibiotic susceptibility: resistant to carbapenems and ampicillin
A. Serratia marcescens
B. Hafnia alvei
C. Enterobacter cloacae
D. Klebsiella pneumoniae

A

D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

A patient with a nosocomial pneumonia has a sputum Gram stain that shows many neutrophils and
numerous small gram-negative coccobacilli. The organism grew in 24 hours as a mucoid, nonhemolytic colony on blood agar and a colorless colony on a MacConkey agar. The organism had
the following characteristics:
Oxidase: negative Nitrate: negative
Catalase: positive ONPG: negative
Nitrate: negative Ornithine decarboxylase: negative
Lysine decarboxylase: negative
A. Burkholderia mallei
B. Stenotrophomonas maltophilia
C. Acinetobacter baumannii
D. Pseudomonas putida

A

C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

A college student attended a beach party where raw oysters and other shellfish were consumed.
The next day, he had symptoms of septicemia. The blood cultures grew gram-negative bacilli with
the following characteristics:
Oxidase: positive
MacConkey agar: pink colonies
TCBS: green colonies
O/129 (150 ug): susceptible
String test: with string formation
The most likely organism is:
A. Vibrio alginolyticus
B. Plesiomonas shigelloides
C. Vibrio vulnificus
D. Aeromonas hydrophilia

A

C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Cultures obtain from a dog bite wound produce yellow, tan, and slightly pink colonies on blood and
chocolate agar with margin of fingerlike projections appearing as a film around colonies. Given the
following results at 24 hours, which is the most likely organism?
Oxidase=colorless catalase=no bubbles
Motility: haze on solid surface Nitrate reduction: yellow
Esculin hydrolysis: blackening Indole: yellow
A. Actinobacter species
B. Capnocytophaga species
C. Eikenella species
D. Pseudomonas specie

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

A slow growing, orange pigmented, acid fast bacillus was isolated from a cervical lymph node of a
child with symptoms of cervical adenitis. With the following biochemical test results:
Catalase: positive ->45mm Nitrate reduction: pink
Urease: pink Tween 80: yellow
The most likely etiological agent in this case would be
A. Mycobacterium avium-intracellulare
B. Mycobacterium chelonei
C. Mycobacterium fortuitum
D. Mycobacterium scrofulaceum

A

D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

A 75-year-old woman presented with a history of decreased appetite, weight loss, and progressive
decline in mental status over a period of 1 week. Laboratory data included the following: increased
WBC count, decreased platelet count, urinalysis showed no evidence of infection. 4 blood cultures
obtained revealed a green pigmented colony, oxidase positive, non-fermenting gram-negative
bacilli with the following biochemical test results:
O/F: open tube: yellow, closed tube: green Nitrate reduction: yellow
Catalase: with bubbles formation Gelatin hydrolysis: gel solidifies
ONPG: yellow Esculin hydrolysis: no blackening
The most likely microorganism is:
A. Pseudomonas fluorescens
B. Pseudomonas stutzeri
C. Pseudomonas luteola
D. Pseudomonas putida

A

D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which of the following microorganisms is/are belong to Non-TB Mycobacterium?
I. Mycobacterium caprae
II. Mycobacterium marinum
III. Mycobacterium tuberculosis
IV. Mycobacterium gordonae
A. I, III
B. II, IV
C. I, II, IV
D. III

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which of the following statements is/are correct about the classification of atypical mycobacteria
I. Scotochromogen develops yellow to orange pigment in dark or light exposure
II. Group IV are rapid growers, grow on medium after more than 7 days of incubation.
III. Photochromogen develops yellow pigment in the dark
IV. Non-chromogen develops tan colonies
A. II, IV
B. I, IV
C. II, III
D. I, III

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Smooth gray colonies showing no hemolysis are recovered from an infected cat scratch on blood
and chocolate agar but fail to grow on MacConkey agar. The organisms are gram-negative
pleomorphic rods that are both catalase and oxidase positive and strongly indole positive. The
most likely organism is:
A. Capnocytophaga spp.
B. Pasteurella spp.
C. Proteus spp.
D. Pseudomonas spp.

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

A gram-negative coccobacillus was isolated from an infected cat bite. The isolate grew on blood
agar with a musty smell, but did not grow on MacConkey agar. It was catalase, indole, and oxidase
positive and negative to urease. Which one of the following is the most likely identity of this isolate?
A. Pasteurella canis
B. Pasteurella multocida
C. Eikenella corrodens
D. Pasteurella bettyae

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

A urine culture had the following culture results:
Sheep blood: swarming
Columbia CNA: no growth
MacConkey:
1. >100,000 CFU/mL nonlactose-fermenter
2. >100,000 CFU/mL nonlactose-fermenter with red pigment
The isolates from MacConkey agar had the following biochemical reactions:
Biochemical tests Isolate 1 Isolate 2
TSI Alkaline/acid Alkaline/acid
Urea Positive Negative
TDA Positive Negative
H2S Positive Negative

The organisms are most likely:
a. Proteus vulgaris and Enterobacter cloacae
b. Proteus mirabilis and Serratia marcescens
c. Morganella morganii and Klebsiella pneumoniae
d. Providencia stuartii and Serratia liquefaciens

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

A child was bitten on the arm by her sibling and the resulting wound grew a slender gram-negative
bacillus that has the following characteristics:
Growth on SBA: colonies that “pit” the agar Colonies odor: like bleach
Catalase: negative Oxidase: positive
TSI: no growth
The identification of this organism is:
A. Aggregatibacter aphrophilus
B. Eikenella corrodens
C. Cardiobacterium hominis
D. Kingella oralis

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

A mixture of slender gram-negative rods and coccobacilli that tend to form rosette filaments was
recovered from blood cultures following a patient’s root canal surgery. Given the following results
after 48 hours, what is the most likely organism?
Catalase = Negative
Oxidase = blue
Indole = red ring
Carbohydrate fermentation(sucrose) = yellow
Colonial Morphology
Growth on blood and chocolate agar = with pitting of agar
Growth on MacConkey agar = colorless
A. Eikenella corrodens
B. Actinobacillus spp.
C. Cardiobacterium hominis
D. Proteus spp.

A

C

17
Q

Which of the following statements is/are TRUE about the two forms of Hansen’s disease?
I. Tuberculoid leprosy has peripheral nerve involvement and loss of sensation.
II. Lepromatous leprosy has progressive and symmetric nerve damage
III. Tuberculoid leprosy ineffective cell mediated immune response
IV. Lepromatous leprosy effective cell mediated immune response
A. I, II
B. III, IV
C. I, III
D. II, IV

A

A

18
Q

Which of the following is the best media for the cultivation of Vibrio species?
A. TCBS, Clary-Blair medium, SSA
B. TCBS, Selenite-F, MacConkey, SSA
C. TCBS, Alkaline Peptone Water, MacConkey
D. TCBS, BAP, Alkaline Peptone Water

A

C

19
Q

A 38-year-old menstruating woman went to the Emergency Room with a 104 Fahrenheit temperature, red rashes
from her extremities, and an indication of severe dehydration because of diarrhea and vomiting. An increased White
Blood Cell Count predominantly Neutrophils was reported in the Complete Blood Count. Beta-hemolytic colonies
were shown on Blood Agar Plate.

  1. What is the virulence factor that can cause this infection?
    A. Epidermolytic toxin A
    B. Heat-Stable toxin B
    C. Toxic Shock Syndrome Toxin-1
    D. Beta-lactamase
  2. What is the initial step to perform to identify the microorganism?
    A. Perform catalase test
    B. Perform gram staining
    C. Perform Coagulase test
    D. Perform Novobiocin Susceptibility test
  3. What is the most likely microorganism?
    A. Staphylococcus lugdunensis
    B. Methicillin Resistant Staphylococcus aureus
    C. Staphylococcus haemolyticus
    D. Staphylococcus aureu
A
  1. C
  2. B
  3. D
20
Q

Associated with epidemic cholera which is positive on oxidase, catalase, and polymyxin B
susceptibility and with agglutination on anti-Ogawa reagent.
A. Vibrio cholerae O1 Classical, Inaba
B. Vibrio cholerae O1 El Tor, Inaba
C. Vibrio cholerae O1 El Tor, Ogawa
D. Vibrio cholerae O1 Classical, Ogawa

A

D

21
Q

A CSF was submitted in the bacteriology section for gram staining, culture, and sensitivity. A small, smooth
translucent, narrow zone of Beta-hemolysis was seen in the Blood Agar Plate. With umbrella-shaped motility
into the semi-solid tube and positive in the Bile Esculin test. The gram stain revealed gram-negative bacilli.
The colonial morphology and presumptive tests are highly suggested for Listeria monocytogenes. What is
the possible reason for the Gram staining result?
A. prolonged staining using the counter stain
B. failure to perform the heat fixation
C. prolonged staining using the primary stain
D. prolonged decolorization

A

D

22
Q

A CSF sample from a patient with meningitis produced many colonies of gram-negative diplococci on a
Chocolate Agar Plate that were also present in many colonies in New York City after 48 hours. Given the
results what is the most likely identification?
Catalase- with bubbles Glucose- yellow
Oxidase- blue Lactose- red
Dnase- no clearing Fructose- red
Tributyrin hydrolysis- colorless Maltose- yellow
A. Neisseria lactamica
B. Neisseria sicca
C. Neisseria meningitidis
D. Neisseria elongata

A

C

23
Q

A 15-year-old child was admitted to the hospital due to a high-grade fever, severe headache, and stiff neck.
The gram stain revealed Gram-positive bacilli with complete hemolysis in Blood Agar Plate and blackening in
Bile Esculin Hydrolysis, and purple in Hippurate Hydrolysis test. What is the possible microorganism isolated?
A. Bacillus anthracis
B. Neisseria meningitidis
C. Listeria monocytogenes
D. Streptococcus pneumoniae

A

C

24
Q

Which of the following statements is/are TRUE about gram-positive microorganisms?
I. Produce exotoxins
II. Thick layered loosely bound of N-acetylmuramic acid and N-acetylglucosamine.
III. High level of Lipoprotein and lipid
IV. Absence of Outer membrane
A. I, II, IV
B. I, IV
C. II, IV
D. II, III

A

B

25
Q

A young boy who routinely bites his fingernails develops a wound on his finger. A culture reveals alpha-hemolytic, dry colonies on the Blood Agar Plate that is catalase negative, resistant to optochin, and 6.5%
NaCl negative. The gram stain of the colony is gram-positive cocci in chains. The organism is most likely
A. Enterococcus faecium
B. Enterococcus faecalis
C. Viridans species
D. Streptococcus agalactiae
E. Streptococcus pneumoniae

A

C

26
Q

A cotton swab sample from a black eschar lesion was submitted for culture and sensitivity. After 24 hours of
incubation at 37C, there was moderately heavy growth on the Blood Agar plate but no growth on Mac Conkey
Agar Plate. The colonies were non-hemolytic, non-pigmented, ground glass surfaces with irregular margins.
What is the causative agent?
A. Bacillus thuringiensis
B. Bacillus mycoides
C. Bacillus anthracis
D. Bacillus cereus

A

C

27
Q

A food poisoning outbreak was reported at Barangay Manipis. Abdominal cramps, vomiting, and severe
diarrhea were the signs and symptoms manifested by the infected member of the barrio. Pre-heated foods
were the source of the outbreak. The gram-staining revealed Gram-positive bacilli. What is the most likely
bacteria?
A. Bacillus cereus
B. Bacillus anthracis
C. Staphylococcus aureus
D. Listeria monocytogenes

A

A

28
Q

An isolate of an unknown beta-hemolytic Streptococcus is streaked perpendicular to a streak of beta-lysinproducing Staphylococcus aureus. After incubation, a zone of arrowhead hemolysis is noted at the interface
of the 2 streaks. What is the name of the test and the presumptive identification of the unknown
Streptococcus?
A. Hippurate hydrolysis and Group B Streptococci
B. CAMP test and Group A Streptococci
C. Hippurate hydrolysis and Group A Streptococci
D. CAMP test and Group B Streptococci

A

D

29
Q

. A 65-year-old male has 2 sets of blood cultures that grow gram-positive cocci after being admitted to the
hospital with an oozing leg wound spot operation. The infected area is red, swollen, and warm to the touch.
A red line has appeared at the sight of the wound and is beginning to travel up the leg. Biochemicals
performed from the beta-hemolytic colonies on the sheep blood agar plate reveal:
CAMP: no arrowhead formation Bacitracin: Sensitive
Hippurate: colorless NaCl: clear
PYR: red Bile esculin: colorless
Most likely the pathogen.
A. Group A Streptococci
B. Group B Streptococci
C. Staphylococcus aureus
D. Enterococcus faecalis

A

A

30
Q

A small, gray-white and gamma-hemolytic colonies in Blood Agar Plate. With the following laboratory test
results:
Catalase: with effervescence PYR: red
Microdase: colorless MSA: pink colonies
Tube coagulase test: no clots Taxo A: 6 mm
Novobiocin Test: 18mm Dnase: no clearing
What is the microorganism?
A. Staphylococcus haemolyticus
B. Staphylococcus warneri
C. Staphylococcus epidermidis
D. Staphylococcus capitis

A

C

31
Q

Which feature distinguishes Erysipelothrix rhusiopathiae from other clinically significant non-spore-forming,
gram-positive, facultatively anaerobic bacilli?
A. Catalase negative
B. H2S production
C. Esculin hydrolysis
D. Urease production

A

B

32
Q

A Gram stain of sputum revealed many polymorphonuclear leukocytes and intracellular gram-negative
diplococci. Culture and tests were as follows:
Catalase- with bubbles DNase- clearing
Oxidase- blue Lactose- red
Glucose- red Sucrose- red
Tributyrin hydrolysis- blue Maltose- red
A. Neisseria gonorrheae
B. Moraxella catarrhalis
C. Neisseria flavescens
D. Neisseria cinerea

A

B

33
Q

A Maine fisherman develops a lesion on his right hand. Gram-positive rod-shaped organisms grow from
wound aspirate fluid. Biochemical tests reveal that the organism is catalase, oxidase, and nitrate-negative.
On TSI slants, it produces an acid slant and butt with H2S. The organism isolated is:
A. Erysipelothrix rhusiopathiae
B. Listeria monocytogenes
C. Bacillus anthracis
D. Corynebacterium diphtheriae
E. Streptococcus viridans

A

A

34
Q

A 55-year-old female visited their family physician to consult her vaginal discharge with an unpleasant odor.
She was advised to submit her vaginal discharge in the bacteriology section for gram staining, culture, and
sensitivity. Few Squamous epithelial cells with overlapping gram-positive bacilli. What is a microorganism?
A. Lactobacillus acidophilus
B. Ureaplasma urealyticum
C. Gardnerella vaginalis
D. Neisseria gonorrhoeae

A

C

35
Q

An 8-year-old girl visits the Emergency Department with symptoms of vomiting and malaise. Her mother
also notes that she has been very irritable. The girl was recently seen in the same Emergency Department
for a skull fracture. Upon examination, the physician notes inflammation around the sutures at the skull
fracture site. A spinal tap is performed and sent to the laboratory for Gram stain, culture, and sensitivity. The
Gram stain showed Gram Positive Cocci in clusters. When the culture report is received the physician
switches the patient to an Amoxicillin/Clavulanic Acid. What did the culture report indicate?
A. Streptococcus pneumoniae, sensitive to Penicillin G.
B. Staphylococcus aureus NOT a MRSA
C. Neisseria meningitidis, Beta lactamase positive
D. Haemophilus influenzae Type B, Beta-lactamase negative
E. Corynebacterium diphtheriae, sensitive to Ciprofloxacin

A

B

36
Q

Which of the following microorganism have a glutamic acid capsule?
I. Streptococcus pneumoniae
II. Bacillus anthracis
III. Neisseria meningitidis
IV. Erysipelothrix rhusiopathie
A. I, II, III, IV
B. I, II, III
C. II only
D. III

A

B

37
Q

An 88-year-old male presents with fever, nausea, and headache. The patient reported a diffuse headache
accompanied by malaise, fatigue, and nausea without vomiting. According to the patient, he frequently attends
cookout parties and enjoys fruits, salads, wine, and cheese. The blood culture was positive for short, grampositive bacilli. Sheep blood agar plate grew round and translucent colonies which have a narrow zone of beta
hemolysis as shown on our plate. The organism was catalase positive and motile at 25 degrees Celsius. It
showed end-over-end tumbling motility in a wet prep and an umbrella pattern in a semi-solid motility medium.
What is likely the microorganism?
A. Bacillus cereus
B. Staphylococcus aureus
C. Bacillus anthracis
D. Listeria monocytogenes

A

D

38
Q

A fecal specimen, inoculated to xylose lysine deoxycholate (XLD) and Hektoen enteric (HE)
produced colonies with black centers. Additional testing results are as follows:
Biochemical screen:
Glucose: positive Lysine decarboxylase: positive
H2S: positive Urea: negative
ONPG: negative Indole: positive
Citrate: negative
Serological test:
Polyvalent: no agglutination
Group A: no agglutination
Group Bl: no agglutination
Group C: no agglutination
Group D: no agglutination
Group Vi: no agglutination
The most probable identification is:
A. Edwardsiella tarda
B. Salmonella arizonae
C. Shigella flexneri
D. Proteus mirabilis

A

B

Bacte Lec [Finals] (59 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions