Brainscape's Knowledge GenomeTM

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


See full index

GRAM NEGATIVE COCCI AND GRAM NEGATIVE BACILLI > ENTEROBACTERIACEAE > Flashcards

ENTEROBACTERIACEAE Flashcards

1
Q

Enterobacterias are commensal floras of the…

A

Intestinal tract

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

Enterobacterias that are not part of a normal flora

A

Salmonella
Shigella
Yersinia

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

Microscopic appearance of Enterobacterias

A

Gram-negative straight rods or coccobacilli with rounded ends

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

Culture morphology of Enterobacterias

A

Large, smooth, gray colonies (except Klebsiella and Enterobacter)
Non hemolytic (except E. Coli - beta hemolytic)

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

Characteristics of Enterobacteriaceae

A

Gram negative straight rods or coccobacilli
Non hemolytic (except E. Coli - beta hemolytic)
Motile (except Klebsiella, Shigella, and Yersinia)
Non encapsulated (except Klebsiella, and Enterobacter)
Glucose fermenter
Reduce nitrate to nitrite
Some may grow at low temperature: 1-5ºC (Serratia and Yersinia)

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

Non motile Enterobacteriaceae

A

“SKY”

Shigella
Klebsiella
Yersinia

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

Motility organelle used by Enterobacterias

A

Peritrichous flagella

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

Encapsulated Enterobacterias

A

Klebsiella
Enterobacter

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

Enterobacterias that grow at low temperatures (1-4ºC)

A

Yersinia
Serratia

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

Gram negative cocci
Catalase (+)
Cytochrome oxidase (+) (except Plesiomonas shigelloides)
Alginate liquefaction (+)

A

Enterobacteriaceae

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

Opportunistic Enterobacteriaceae pathogen

A

“PECKS”

Proteus
Enterobacter
Citrobacter
Klebsiella
Serratia

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

Overt/true Enterobacteriaceae pathogen

A

Salmonella typhi
Shigella
Yersinia pestis

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

They are part of the intestinal microbiota of both humans and animals but may produce serious extraintestinal diseases when outside their normal body sites

A

Opportunistic pathogens

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

They are not present as commensal flora of the GIT of humans and only inhabit the bowel at the time of infection. They are generally acquired through ingestion of contaminated food or water.

A

Overt/True pathogens

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

Extended-spectrum-B-lactamase-producing Enterobacterias

A

“EKKstended-…”

Escherechia coli
Klebsiella pneumonia
Klebsiella oxytoca

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

Isolated from urinary tract and cause bacteremia

A

“PEK”

Proteus mirabilis
Escherichia coli
Klebsiella pneumoniae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Antibiotic-resistant genera of Enterobacteriaceae

A

“SEC”

Serratia
Enterobacter
Citrobacter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Enterobacteria associated with diarrhea

A

“YESS”

Yersinia
Escherichia coli
Salmonella
Shigella

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Antigen determinants used for serological identification of Enterobacterias

A

“O” antigen
“H” antigen
“K” antigen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

“O” antigen or…

A

Somatic antigen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

“H” antigen or…

A

Flagellar antigen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

“K” antigen or…

A

Capsular antigen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Heat stable antigen; located in the cell wall

A

“O” antigen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Heat labile antigen; found in the flagellum

A

“H” antigen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Heat labile polysaccharide; covers the O antigen

A

“K” antigen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Which bacterias are serotyped with “O” antigens

A

Escherichia coli
Shigella

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Which bacterias are serotyped with “H” antigen

A

Salmonella

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Which bacterias are serotyped with “K” antigen

A

Escherichia coli
S. enterica subsp. enterica serotype Typhi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Possesses “K1” capsular antigen

A

E. coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Possesses “Vi” capsular antigen

A

S. enterica subsp. enterica serotype Typhi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Aka colon bacillus

A

Escherichia coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Where is Escherichia coli found in humans?

A

Normal bowel flora
Female genital tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

It invades enterocytes lining the large intestine

A

Escherichia coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

It is a primary marker of fecal contamination in water purification

A

Escherichia coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

It is the leading cause of nosocomial infection — UTI

A

Escherichia coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Flat, dry, with pink colonies (MAC)
Beta hemolytic (BAP)
Some strains may be NLF or LF
Greenish metallic sheen (EMB)

A

Escherichia coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

E. coli “O” groups have shown cross reactivity with ___________

A

“O” antigens of Shigella

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Antigenic determinants on Escherichia coli

A

O, H, K antigens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Escherichia coli virulence factors

A

“ECoKI” ~sounds like E. coli~

Endotoxin
Common pili
K1 antigen
Intimin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Escherichia coli virulence factor responsible for neonatal meningitis

A

K1 antigen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Identical to the capsular antigen on Neisseria meningitidis group B

A

K1 antigen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Escherichia coli IMVIC and TSI reaction

A

IMVIC: + + - -
TSI: A/A, (+) gas, (-) H2S

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Formerly called E. coli atypical or enteric group II

A

Escherichia hermanii

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Escherchia with yellow pigmented colonies

A

Escherichia hermanii

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

E. coli strain that does not produce toxin and only attaches to the brush border of the intestinal epithelial cells causing cell damage

A

Enteropathogenic E. coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

E coli strain causing infantile diarrhea (stool without blood)

A

Enteropathogenic E. coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

E coli strain with H antigen and intimin

A

Enteropathogenic E. coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Colonizes the proximal small intestine, causing Traveler’s diarrhea or montezuma’s revenge

A

Enterotoxicogenic E coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Persons with achlorhydia are at risk of getting this E coli strain

A

Enterotoxicogenic E coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Enterotoxicogenic E coli virulence factor

A

Heat stable (ST) and heat-labile (LT) enterotoxin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Infective dose of Enterotoxicogenic E coli

A

10^6 to 10^10

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

E coli strain that penetrates and multiplies within the intestinal epithelial cells, causing dysentery-like or shigella-like infections

A

Enteroinvasive E coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Infection with this E coli strain produces watery diarrhea with WBC

A

Enteroinvasive E coli — dysentery-like or shigella-like infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Enteroinvasive E coli virulence factor

A

Invasin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

E. coli strain positive for Sereny test

A

Enteroinvasive E coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Infective dose of Enteroinvasive E coli

A

10^6

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Associated with hemolytic uremic syndrome an thrombotic thrombocytopenia purpura

A

Enterohemorrhagic E coli serotype 0157:H7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What strain and its toxin is responsible for the destruction of vascular endothelial cells which cause hemorrhagic colitis, and hemolytic uremic syndrome (HUS)?

A

Verotoxin present in Enterohemorrhagic E coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Shiga-like toxin

A

Verotoxin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Causes infection with bloody diarrhea (without WBC)

A

Enterohemorrhagic E coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Shigella-like toxin E coli

A

Enteroinvasive E coli
Enterohemorrhagic E coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

E coli strain with (+) intimin; (-) MUG

A

Enterohemorrhagic E coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

2 types of Enteroadherent E coli

A

Enteroadherent E coli (EAEC)
Diffusely adherent E coli (DAEC)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

E coli strain that adheres to the surface of the intestinal mucosa and causes watery diarrhea, or UTI

A

Enteroadherent E coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

E coli strain that adheres to Hep2 cells forming clumps of bacteria and causes UTIs

A

Diffusely adherent E coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

Enteroadherent E coli virulence factor

A

Fimbriae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

Causes “stacked-brick” appearance of clumped bacterias

A

Diffusely adherent E coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Most common cause of UTIs in humans

A

Uropathogenic E coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

Uropathogenic E coli virulence factor

A

“PAC”

Pili
Aerobactin
Cytolysin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

A test used to test the invasiveness of enteroinvasive Escherichia coli, Shigella species, and Listeria monocytogenes. It is done by inoculating suspension of bacteria into guinea pig’s eye. Severe mucopurulent conjunctivitis and severe keratitis indicates a positive test.

A

Sereny test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

Bacterial adhesion molecule involved in attachment of enteropathogenic and enterohaemorrhagic Escherichia coli to mammalian host cells

A

Intimin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

Vibrio-like E coli

A

Enterotoxigenic E coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

___________ activates guanylate cyclase which stimulates the production of __________

A

Heat-stable enterotoxin (ST)
Cyclic guanosine monophosphate (cGMP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

Induces the secretion of electrolytes and water into the lumen of the intestine resulting to watery diarrhea

A

Cyclic guanosine monophosphate (cGMP)
Cyclic adenosine monophophate (cAMP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

_________ binds to specific gangliosides on the epithelial cells and activates membrane bound adenylate cyclase, which leads to increased production of ________

A

Heat-labile enterotoxin (LT)
Cyclic adenosine monophosphate (cAMP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

AKA Shiga toxicogenic E. coli

A

Enterohemorrhagic E. coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

Biochemical characteristics of Klebsiella

A

KCN (+)
H2S (-)
MR (-)
VP (+)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

Friedlander’s bacillus

A

Klebsiella pneumoniae subsp. pneumoniae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

Formerly known as the bacillus capsulatus

A

Klebsiella pneumoniae subsp. pneumoniae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

The most common isolated spp of Klebsiella

A

Klebsiella pneumoniae subsp. pneumoniae

81
Q

Causative agent of community acquired pneumonia

A

Klebsiella pneumoniae subsp. pneumoniae

82
Q

Causes currant jelly-like sputum

A

Klebsiella pneumoniae subsp. pneumoniae

83
Q

It is a frequent cause of lower respiratory tract infections among hospitalized patients and in immunocompromised hosts

A

Klebsiella pneumoniae subsp. pneumoniae

84
Q

Pink, mucoid colonies (MAC)

Neufeld Quellung test (+)
TSI: A/A, (+) gas, (-) H2S
IMVIC (- - + +)
KCN (+)
Urease (+)
Lysine decarboxylase (+)
Gelatin @ 22ºC (-)
Na alginate utilization (+)

A

Klebsiella pneumoniae subsp. pneumoniae

85
Q

Virulence factor of Klebsiella pneumoniae subsp. pneumoniae

A

Polysaccharide capsule

86
Q

Differential test for Klebsiella pneumoniae subsp. pneumoniae

A

String test (+)

87
Q

Causes chronic atrophic rhinitis (“foul smelling” atrophic rhinitis)

A

Klebsiella pneumoniae subsp. ozanae

88
Q

Causes a granuloma of the nose and oropharynx

A

Klebsiella pneumoniae subsp. rhinoscleromatis

89
Q

Klebsiella species that are indole positive

A

K. oxytoca
K. ornithinolytica

90
Q

Biochemical test:

IMVIC (+ + + +)
Urease (+)
Lysine decarboxylase (+)
Gelatin @ 22ºC (-)

A

Klebsiella oxytoca

91
Q

Resembles Klebsiella on MAC: pink colonies and maybe mucoid colonies

A

Enterobacter

92
Q

Has been isolated with osteomyelitis following traumatic wounds

A

Enterobacter cancerogenous

93
Q

A pathogen in neonates causing meningitis and bacteremia, often coming from powdered infant formula

Culture: yellow-pigmented colonies

A

Cronobacter sakazaki

94
Q

Causes nosocomial outbreak of septicemia due to contaminated IV fluids. It shows “triple decarboxylase negative” reaction

A

Pantoea agglomerans

95
Q

Musty-pungent odor or “potato-like” odor

A

Serratia odoriferae

96
Q

Most clinically significant Serratia spp.

A

Serratia marcescens

97
Q

Causes bacteremic outbreaks in nurseries and cardiac surgery and burn units. It is a contaminant in antiseptic solutions used for joint injections causing an epidemic of septic arthritis

A

Serratia marcescens

98
Q

Causes osteomyelitis following a motorcycle accident

A

Serratia plymuthica

99
Q

It is not known to cause gastroenteritis but is occasionally isolated from stool cultures. It has a distinctive feature: delayed citrate reaction.

A

Hafnia alvei

100
Q

It can infect the proximal kidney tubules and can cause AGN particularly in patients with urinary tract defects or catheterization.

A

Proteus

101
Q

Culture:

“swarming phenomenon” and “burn chocolate” or “burnt-gun powder” odor

A

Proteus

102
Q

Common isolates of Proteus

A

Proteus mirabilis

103
Q

Proteus that is a human pathogen

A

Proteus mirabilis
Proteus vulgaris

104
Q

TRUE OR FALSE

The swarming phenomenon is a result of a tightly regulated cycle of differentiation from standard vegetative cells (swimmers) to hyperflagellated, elongated, polyploidy cells (swarmers) capable of coordinated surface movement

A

TRUE :’)

105
Q

Is a rapid urease producer which encourages renal stone formation (urea splits in urine = increased urine pH). It is isolated from urine, wound, and ear infections.

A

Proteus

106
Q

Biochemical characteristics of Proteus

A

PAD test (+)
LIA (R/A)
IMVIC: (- + v v) P mirabilis; (+ + - v) P vulgaris
TSI: K/A, (+) gas, (+) H2S - P mirabilis
K/A, (+/-) gas, (+) H2S - P vulgaris

107
Q

One of the causes of nosocomial outbreaks involving burn units.
PAD test (+)
IMVIC (+ + - +)
TSI: K/A, (-) gas, (-) H2S

A

Providencia

108
Q

A pathogen of the urinary tracts that also causes diarrheal disease among travelers

A

Providencia rettgeri

109
Q

It has been isolated from noscomial outbreaks in burn units and in urine cultures. It is mostly resistant to antimicrobial agents (together with P rettgeri)

A

Providencia stuartii

110
Q

Providencia spp most commonly found in the feces of children with diarrhea

A

Providencia alcalifaciens

111
Q

Differentiates P rettgeri from P stuartii

A

Christensen’s urea: (+) P rettgeri ; (-) P stuartii

112
Q

Biochemical characteristics of Morganella

A

Same biochemical reaction with P vulgaris except citrate (-)
PAD test (+)
LIA (R/A)
IMVIC (+ + - -)
TSI: K/A, (+/-) gas, (+) H2S

113
Q

Edwardsiella spp pathogenic to humans

A

Edwardsiella tarda

114
Q

It has been isolated from cold-blooded and warm blooded animals
Biochemical test:
Urease (-)
LDC (+)
IMVIC ++—
TSI K/A, (+) gas, (+) H2S

A

Edwardsiella

115
Q

A plant pathogen enterobacteriaceae not significant in human infections

A

Erwinia

116
Q

Colonies on MAC resemble E coli and biochemically resembling Salmonella. It can cause false (+) agglutination test with salmonella

A

Citrobacter

117
Q

Has been associated with endocarditis in IV drug users. The colony morphology resembles Salmonella when isolated from stool cultures.

A

Citrobacter freundii

118
Q

It produces type 1 cephalosporinase

A

Citrobacter freundii

119
Q

It causes nursery outbreaks of neonatal meningitis and brain abscesses

A

Citrobacter koseri

120
Q

The most serous pathogenic Enterobacteria for humans

A

Salmonella

121
Q

An inhabitant of the GI tract of animals. Humans acquire this organism by ingestion of contaminated animal products or improperly cooked poultry, milk, eggs, and dairy products. It may also be transmitted by “human carriers”

A

Salmonella

122
Q

Salmonella biochemical characteristics

A

Motile (except S pullorum and S gallinarum)
Gas (+) (except S gallinarum and S typhi)
H2S (+) (except S paratyphi A)
LDC (+)
KCN (-)
IMVIC (-+-+ / -+—) S typhi
TSI: K/A, (+/-) gas, (+) H2S

123
Q

Salmonella virulence factor

A

Fimbriae
Enterotoxin

124
Q

Main etiologic agent of enteric fever

A

Salmonella typhi

125
Q

Etiologic agents of paratyphoid fever

A

Salmonella paratyphi A, B, C
Salmonella choleraesuis

126
Q

Salmonella isolated from lizards and other cold-blooded animals

A

Salmonella bongori

127
Q

Most common Salmonella strain associated with gastroenteritis delete

A

Salmonella enterica subsp. enterica

128
Q

Causes peanut-butter outbreak

A

Salmonella typhimurium

129
Q

Diseases caused by Salmonella

A

Gastroenteritis
Typhoidfecer
Bacteremia

130
Q

Gastroenteritis is one of the most common forms of “food poisoning.” This is spread by using contaminated cooking utensils. Inadequate refrigeration also allows the growth and multiplication of the organism. Poultry, eggs, milk, and handling of pets are the main source of infection. Symptoms include nausea, vomiting, fever and chills, watery diarrhea and abdominal pain.

What is the causative agent?

A

Salmonella enterica subsp enterica

131
Q

Infective dose of Salmonella enterica

A

10^6

132
Q

A febrile disease that results from the ingestion of contaminated food originating from infected individual or carriers, contaminated food and water, and fomites. Outbreaks can also be caused by improper disposal of sewage, poor sanitation and lack of modern water system. Symptoms include malaise, anorexia, lethargy, myalgia, and continuous frontal dull headache.

A

Enteric fever/typhoid fever

133
Q

Causative agent of typhoid fever

A

Salmonella typhi

134
Q

Characteristic papules that appear during the second week of typhoid fever

A

“Rose spot” blanching rose-colored papules that appear around the periumbilical region

135
Q

The site of long-term carriage of Salmonella typhi for individuals who have recovered from the infection

A

Gall bladder

136
Q

Causes necrotizing cholecystitis and Peyer’s patches

A

Salmonella typhi

These are the complications of typhoid fever

137
Q

Salmonella resistant to gastric acids and, on reaching the proximal end of the small intestine, invades and penetrates the intestinal mucosa

A

Salmonella typhi

138
Q

Characterized by prolonged fever and intermittent bacteremia. This occurs with and without extraintestinal foci of infection caused by nontyphoidal Salmonella.

A

Bacteremia

139
Q

Salmonella responsible for bacteremia

A

Non typhoidal salmonella: S typhimurium, S paratyphi, and S cholerasuis

140
Q

Treatment for chronic state of enteric carriers

A

Cholecystectomy is the only remedy

141
Q

What specimen for salmonella id is collected for the 1st week of infection?

A

Blood

142
Q

What specimen for salmonella id is collected for the 2nd week of infection?

A

Stool

143
Q

What specimen for salmonella id is collected for the 3rd week of infection?

A

Urine

144
Q

Closely related to genus Escherichia. It is an intracellular organism that multiplies in the cells of the colon epithelium.

A

Shigella

145
Q

Mode of acquisition of Shigella

A

Flies, fingers, food and feces (the four F’s) and water by infected persons (fecal-oral route)

146
Q

Culture:

Clear, fragile, NLF colonies
colorless colonies without black centers (SSA)

A

Shigella

147
Q

Shigella reservoirs

A

Humans only

148
Q

Most virulent Shigella species

A

Shigella dysenteriae

149
Q

Gay bowel syndrome

A

Shigella flexneri

150
Q

Shigella virulence factor

A

Shiga toxin

151
Q

Shigella antigenic structures

A

Somatic O

152
Q

Shigella specimen

A

Rectal swab

153
Q

Shigella biochemical characteristics

A

Non motile
Mannitol fermenter (except Shigella dysenteriae)
Does not utilize acetate or mucate as source of carbon
(-) gas from glucose (except Shigella flexneri)
Urease (-)
LDC (-)
IMVIC (v+—)
TSI: K/A, (-) gas, (-) H2S

154
Q

Susceptible to disinfectants and high concentrations of acids and bile

A

Shigella

155
Q

Why are Shigella specimens plated immediately after collection

A

Shigella is sensitive to pH changes (susceptible to acidic stool)

156
Q

Is unique in its ability to decarboxylate ornithine; late lactose fermenter; ONPG (+)
Infection from this organism is self-limiting and usually characterized by fever and watery diarrhea

A

Shigella sonnei

157
Q

Most common causative agent of bacillary dysentery

A

Shigella dysenteriae type 1

158
Q

Characterized by acute inflammatory colitis and bloody diarrhea (blood mucus, and WBCs) caused by the penetration of the intestinal epithelial cells by the organism, following attachment of the organisms to mucosal cell. Symptoms include fever, chills, abdominal cramps, painful bowel movement, and tenesmus.

A

Bacillary dysentery

159
Q

Its presence usually indicates improper sanitary conditions and poor personal hygiene

A

Shigella dysenteriae type 1

160
Q

Infective dose of Shigella dysenteriae

A

<200 bacilli

It is highly communicable because of its low infective dose required to produce the disease

161
Q

AKA plague bacillus

A

Yersinia pestis

162
Q

Yersinia pestis is considered as a ________ bioterrorism agent

A

Class A bioterrorism agent

163
Q

The only Enterobacteriaceae transmitted to humans by the bite of an infected flea

A

Yersinia pestis

164
Q

Vector of transmission for Yersinia pestis

A

Xenopsylla cheopis

165
Q

Where do Yersinia pestis multiply?

A

Inside phagocytes

166
Q

Protein responsible for the down-regulation of anti-bacterial responses of the host which allows Yersinia pestis to survive and multiply inside phagocytes

A

Yersinal plasmid-encoded outer membrane proteins (YOPS)

167
Q

Microscopic appearance of Yersinia pestis

A

Short, plump rod with “bipolar staining or closed safety pin appearance”

168
Q

Stain used for Yersinia pestis

A

Wayson or methylene blue stain

169
Q

Culture morphology of Yersinia pestis

A

Pinpoint colonies; grows best at 25º-30º C
Stalactite pattern (broth culture)

170
Q

Yersinia pestis virulence factor

A

Endotoxin
Coagulase
Fibrinolysin

171
Q

Mode of transmission of plague

A

Is a disease of the rodents transmitted to humans by fleas
Ingestion of contaminated animal tissues
Inhalation of contaminated airborne droplets

Once inside the human body, the bacteria multiplies in the blood and lymph

172
Q

2 forms of plague

A

Bubonic plague
Pulmonary plague

173
Q

Associated with high fever and painful inflammatory swelling of axilla and groin. It results from the bite of an infected flea

A

Bubonic plague

174
Q

Occurs secondary to the bubonic plague. It is acquired by close contact with other victims.

A

Pulmonary plague

175
Q

The most commonly isolated Yersinia

A

Yersinia enterocolitica

176
Q

Causative agent of waterborne gastroenteritis

A

Yersinia enterocolitica

177
Q

How is Yersinia enterocolitica isolated from a stool specimen?

A

Requires cold enrichment technique (4ºC) using phosphate buffered saline for several weeks

178
Q

Biochemical characteristics of Yersinia enterocolitica

A

Motile at 22ºC but not at 35ºC
Ferments sucrose and mannitol
IMVIC (v+—)
TSI: K/A, (-) gas, (-) H2S

179
Q

Microscopic appearance of Yersinia enterocolitica

A

Coccobacilli with bipolar staining

180
Q

Culture morphology of Yersinia enterocolitica

A

“Bull’s eye colonies” (dark red or burgundy centers with transparentborders) in CIN medium

181
Q

Optimum temperature for Yersinia enterocolitica

A

25º-30ºC

182
Q

Selective medium for Yersinia enterocolitica

A

Cefsulodi-irgasan-novobiocin (CIN) agar

183
Q

Yersinia enterocolitica reservoir

A

Swine
Dogs
Cats
Rabbits
Cattle

184
Q

Infections caused by Yersinia enterocolitica

A

Enterocolitis — waterborne gastroenteritis
Appendicitis-like syndrome
Arthritis
Erythema nodosum

185
Q

Yersinia enterocolitica mode of acquisition

A

Consumption of incompletely cooked food and dairy products, and handling pets

186
Q

A pathogen of rodents, particularly guinea pigs

A

Yersinia pseudotuberculosis

187
Q

Yersinia pseudotuberculosis reservoir

A

Farm and domestic animals (birds)

188
Q

Yersinia pseudotuberculosis mode of acquisition

A

Close contact with infected animals on their fecal material and ingestion of contaminated drink and food

189
Q

Biochemical characteristic of Yersinia pseudotuberculosis

A

Motile at 18º-25ºC
Urease (+)
Ferments rhamnose

190
Q

At what temperature is Yersinia pseudotuberculosis motile?

A

18º-25ºC

191
Q

At what temperature is Yersinia enterocolitica motile?

A

22ºC but not at 35ºC

192
Q

Antigens present in Yersinia enterocolitica

A

V and W antigens

193
Q

At what temperature is Yersinia pestis motile?

A

They are nonmotile

194
Q

The only oxidase (+) member of Enterobacteriaceae

A

Plesiomonas shigelloides

195
Q

Microscopic appearance of Plesiomonas shigelloides

A

Gram negative straight bacilli; occurs singly, in pairs, short chains or filamentous forms

196
Q

Culture morphology of Plesiomonas shigelloides

A

Shiny, opaque, smooth, and nonhemolytic (BAP)
white to pink colonies (Inositol brilliant green bile salt agar)
Opaque “apron-like colonies” (CIN)
(-) growth on TCBS
(+) growth on HEA

197
Q

Plesiomonas shigelloides morphology on CIN

A

Opaque “apron-like” colonies

198
Q

Often cross-agglutinates with Shigella

A

Plesiomonas shigelloides

199
Q

Plesiomonas shigelloides antigenic structures

A

Somatic O
Flagellar H (polar flagella)

GRAM NEGATIVE COCCI AND GRAM NEGATIVE BACILLI (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions