Gram -positive bacilli, Anaerobic, Spore forming, Catalase-negative

Question 1

The toxins produced by the species are acquired through ingestion or open wounds that have
been contaminated with soil

Answer 1

Clostridium

Question 2

Clostridium are motile with peritrichous flagella except for

Answer 2

C. perfringens, C. ramosum, and C.
innocuum

Question 3

clostridium have swollen sporangia except for

Answer 3

C. perfringens

Question 4

They are non-encapsulated except for

Answer 4

C. perfringens

Question 5

They are carbohydrate fermenters except for

Answer 5

C. tatami and C.histolyticum

Question 6

It is the most commonly isolated member of Clostridum in blood culture

Answer 6

Clostridum perfringens(Gas gangrene bacillus)

Question 7

“Boxcar-shaped” bacilli with oral, subterminal spores

Answer 7

Clostridum perfringens(Gas gangrene bacillus)

Question 8

Virulence factor of C. perfringens

Answer 8

Clostridum perfringens(Gas gangrene bacillus)

Question 9

litmus milk-Colonies exhibit a stormy fermentation of milk

Answer 9

Clostridum perfringens(Gas gangrene bacillus)

Question 10

(+) Reverse CAMP test-formation of an “arrowhead-shaped” zone of hemolysis
towards the test organism

Answer 10

Clostridum perfringens(Gas gangrene bacillus)

Question 11

It is a life-threathening destruction of muscle and other tissues
It is accompanied by bullae, pain, swelling, serous discharge, discoloration and tissue
necrosis

Answer 11

Gas gangrene-Clostridum perfringens(Gas gangrene bacillus)

Question 12

It is caused by the ingestion of Beta-enterotoxin in contaminated food
Improperly stored food allows the germination of the spores and growth of vegetative
bacteria
Symptoms: Bloody diarrhea and abdominal pain

Answer 12

Clostridial necrotizng enteritis or enteritis necroticans

Question 13

It is a soil and environmental inhabitant
The endospores are found in the soil, dust, and feces of many farm animals

Answer 13

Clostridium tetani (Tack head bacillus)

Question 14

Virulence factor of Clostridium tetani

Answer 14

Tetanospasmin (neurotoxin)

Question 15

Microscopy: cells are with terminal spores and swollen sporangis that have a “drumstick” or
“tennis racket” appearance

Answer 15

Clostridium tetani (Tack head bacillus)

Question 16

Biochemical test: (+) gelatinase, and indole; (-) lecithinase and lipase

Answer 16

Clostridium tetani (Tack head bacillus)

Question 17

It is an endopeptidase that selectively cleaves the synaptic vesicle membrane protein,
synaptobrevin
It causes tension or cramping and twisting in skeletal muscles that surround the wound, and
tightness of the jaw muscle

Answer 17

Tetanospasmin

Question 18

It is characterized by trismus or lock jaw and risus sardonicus or distorted grin

Answer 18

Tetanus

Question 19

It occurs when the organism enters an open wound and spreads a potent toxin that mediates
generalized muscle spasm

Answer 19

Tetanus

Question 20

Symptom: Muscular rigidity, difficulty in swallowing, rigidity of the abdomen, chest, back, and
limbs
Incubation period: 3 to 21 days

Answer 20

Tetanus

Question 21

is contracted through the use of contaminated instruments on newborns

Answer 21

Tetanus neonatorum

Question 22

It is found in soil and aquatic sediments
It is a potential bioterrorism agent
It is characterized by the presence of subterminal spores

Answer 22

Clostridium botulinum (―Canned food‖ bacillus)

Question 23

Canned food bacillus

Answer 23

Clostridium botulinum (―Canned food‖ bacillus)
q

Question 24

a neurotoxin that is considered as one of the most potent
natural toxins known to man

Answer 24

Botulism toxin

Question 25

It selectively cleaves the synaptic vesicle membrane protein, synaptobrevin, thus preventing
exocytosis and the release of the neurotransmitter, acetlcholine

Answer 25

Botulism toxin

Question 26

It requires a small amount to produce paralysis and death

Answer 26

Botulism toxin

Question 27

Botulism antigens:

Answer 27

A to G

Question 28

The antigens that cause human diseases are

Answer 28

A, B and E

Question 29

It is characterized by double or blurred vision, impaired speech, difficulty in swallowing,
weakness, and paralysis

Answer 29

Botulism

Question 30

It results from the ingestion of preformed toxin in preserved or meat-based food

Answer 30

Foodborne botulism

Question 31

It is commonly caused by botulism toxin A

Answer 31

Foodborne botulism

Question 32

It is an actual infection that is caused by ingesting the organism from honey or
through breastfeeding for infants

Answer 32

Infant botulism

Question 33

It is the most common cause of antibiotic-associated diarrhea and pseudomembranous colitis

Answer 33

Clostridium difficile

Question 34

It is acquired in the hospitals by individuals who are receiving antibiotics

Answer 34

Clostridium difficile

Question 35

It is an “infection control dilemma” among hospitalized patients

Answer 35

Clostridium difficile

Question 36

It ferments fructose-producing formic acid that changes the color of medium from pink to yellow

Answer 36

Clostridium difficile

Question 37

Virulence factor: Toxin A (enterotoxin) and toxin B (cytotoxin)
Microscopy: Chains up to 6 cells that are aligned from end to end with oval, subterminal
endospores

Answer 37

Clostridium difficile

Question 38

Cycloserine-cefoxitin-fructose agar (CCFA)-colonies exhibit a yellow color and a
“ground-glass” appearance

Answer 38

Clostridium difficile

Question 39

BAP-Colonies exhibit a ―”horse-stable” odor; are non-hemolytic‘ and produce a
fluorescent chartreuse under a long UV light wave

Answer 39

Clostridium difficile

Question 40

o Food and fecal specimens that are suspected of C. perfringens food poisoning should be
transported at

Answer 40

4 degrees celsius

Question 41

Unacceptable specimes for anaerobic culture of C. difificile

Answer 41

a. swabs
b. sputum
c. bronchial washings
d. feces and effluents from ileostomy and colostomy
gastric and small bowel contents

Question 42

It is used to differentiate the aerotolerant strains of Clostridum (catalase negative
from Bacillus (catalase-positive)
Reagent: 15% H2O2
(+) Result: Formation of bubbles

Answer 42

Catalase test

Question 43

It is performed using an EYA plate and C. perfringens type A antitoxin.
(+) Result: Inhibition of the lecithinase reaction that is produced by C. perfringens

Answer 43

Direct Nagler Test

Question 44

It is a definitive identification test for C. botulinum
It detects the presence of neurotoxins in serum or feces

Answer 44

Mouse neutralization test

Question 45

It is used to confirm the presence of C. perfringens
(+) Result: Formation of an ―”arrowhead-shaped” zone of hemolysis at the
intersection of the 2 streaks toward the Clostridum isolates

Answer 45

Reverse CAMP test

Question 46

It is the gold standard test for the detection of the C. difficile toxin type B
It requires two to three days to achieve a positive result

Answer 46

Cell culture cytotoxicity test

Question 47

+) Lipase reaction: Colonies exhibiting a ―”mother-of-pearl” or ―”gasoline-on-water”
appearance

Answer 47

C. bitulinum and C. novyi

Question 48

It is the most commonly isolated anaerobes from blood cultures

Answer 48

Bacteroides fragilis

Question 49

It is a Beta-lactamase producer; and is non-motile and saccharolytic

Answer 49

Bacteroides fragilis

Question 50

Bacteroides bile esculin (BBE) agar-Colonies exhibit a gray color and growth witj 20%
bile, and cause the blackening of the originally yellow-colored agar

Answer 50

Bacteroides fragilis

Question 51

Biochemical test: (+) Esculin hydrolysis

Answer 51

Bacteroides fragilis

Question 52

It is a significant cause of intra-abdominal abscesses

Answer 52

Bacteroides fragilis

Question 53

It is the most common cause of actinomycosis

Answer 53

Actinomyces israelii

Question 54

It is part of the indigenous microbiota of the oral cavity

Answer 54

Actinomyces israelii

Question 55

It is frequently isolated from blood cultures, but its presence also indicates contamination of the
patient‘s skin due to the improper cleansing of the site prior to a phlebotomy

Answer 55

Propionobacterium acnes

Question 56

The species of this genus are pleomorphic, Gram-positive rods
It non - motile, and may also be considered as an aerotolerant anaerobe

Answer 56

Lactobacillus

Question 57

It is part of the indigenous microbiota of the mouth, GIT, and vaginal canal
It protects the female genital tract from urogenital infections

Answer 57

Lactobacillus acidophilus

Question 58

Differential medium: Tomato juice agar (pH 3 to 4)

Answer 58

Lactobacillus acidophilus

Question 59

Biochemical test: (-) Catalase , H2S and esculin hydrolysis

Answer 59

Lactobacillus acidophilus