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Clinical Bacteriology Lec > Gram-Negative Bacilli > Flashcards

Gram-Negative Bacilli Flashcards

1
Q

General characteristics of Enterobacteriaceae

A
  1. Gram (-) Bacilli
  2. NSF (Non-spore forming)
  3. Some are motile and nonmotile
  4. FA (Facultative anaerobes)
  5. (-) Oxidase
  6. Ferment glucose but otherwise vary in carbohydrate utilization
  7. Most reduce Nitrate to Nitrites
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2
Q

Name the motile Enterobacteriaceae

A

peritrichous

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3
Q

Name the nonmotile Enterobacteriaceae

A

Klebsiella, Shigella, Yersinia

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4
Q

Which surface antigen is known as the somatic antigen or cell wall antigen

A

O antigen

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5
Q

Characteristics of O antigen

A

Heat and alcohol stable

Usually detected by bacterial agglutination

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6
Q

Which surface antigen is known as the capsular antigen or fimbrial antigen

A

K antigen

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7
Q

True or False: The K antigen is external to the O antigens on some but not all Enterobacteriaceae

A

True

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8
Q

Characteristics of K antigen

A

Heat labile and may be associated with virulence

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9
Q

Which surface antigen is known as the flagellar antigen

A

H antigen

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10
Q

Characteristics of H antigen

A

Heat- and alcohol-labile antigen

Found on the surface of flagella

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11
Q

How can H antigens be presented within a single serotype ?

A 
Either or Both of two forms:
Phase 1 (lower case letters)
Phase 2 (arabic numerals)
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12
Q

Phase variation occurs with which surface antigen

A

H antigen

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13
Q

General characteristics of Enterobacteriaceae coliforms

A
  1. Aerobic and FA
  2. NSF
  3. Gram (-) rods
  4. Cytochrome oxidase (-)
  5. Capable of growth in the presence of bile salts
  6. Lactose fermenters
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14
Q

What are the normal enteric flora do Coliforms include ?

A

Escherichia, Klebsiella, Enterobacter, and Citrobacter

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15
Q

Differentiate fecal coliforms from non fecal coliforms

A

Fecal coliforms:

  1. Ferment lactose at 44.5°C
  2. the indicator organism of choice for fecal contamination

Nonfecal coliforms:

  1. Does not ferment lactose
  2. their detection in water supply or other materials may mean false positive for fecal contamination
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16
Q

Which noncoliforms are included in the opportunistic, normal gut flora ?

A

Proteus, Morganella, Providencia, Edwardsiella, Serratia, Hafnia

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17
Q

Which noncoliforms are included in the pathogenic enterics ?

A

Salmonella, Shigella, Yersinia enterocolitica and Y. pseudotuberculosis

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18
Q

Which noncoliforms are included in the pathogenic, non-enteric ?

A

Yersinia pestis

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19
Q

Habitat of enterobacteriaceae

A

ubiquitous in nature

most are found in intestinal tract (colon)

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20
Q

This coliform is also referred to as colon bacillus

A

Escherichia coli

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21
Q

Where do E. coli strains that cause UTI originate from ?

A

Large intestine as resident biota

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22
Q

Why is UTI of E. coli more common in women ?

A

Due to their relatively short urethras that promote ascending infection to the bladder (cystitis) and occasionally, the kidneys

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23
Q

What are uropathogenic E. coli ?

A

Strains that cause lower urinary tract and acute pyelonephritis in otherwise healthy hosts

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24
Q

How does P fimbrae assist uropathogenic E. coli ?

A

Allow the bacteria to attach to the urinary epithelial mucosa and not be washed out with urine flow

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25
Q

How do hemolysins assist uropathogenic E. coli ?

A

Kill immune effector cells and inhibit phagocytosis and chemotaxis of certain white blood cells

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26
Q

How do aerobactins affect uropathogenic E. coli ?

A

Allows the bacterial cell to chelate iron, as free iron is not available in the body for the bacteria to use

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27
Q

This is also known as enterovirulent E. coli

A

Diarrheagenic E. coli

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28
Q

What are the 5 categories of diarrheagenic E. coli ?

A 
Enteropathogenic E. Coli
Enterotoxigenic E. coli
Enterohemorrhagic E. coli
Enteroinvasive E. coli
Enteroaggregative E. coli
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29
Q

Characteristics of EPEC

A

low-grade fever, malaise, vomiting, and profuse, watery diarrhea

Stool typically contains large amounts of mucus

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30
Q

Adhere to intestinal epithelial cells in localized microcolonies producing characteristic histopathologic lesions known as “attaching and effacing lesions”

A

Enteropathogenic E. coli

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31
Q

What facilitates the “attachment” or promotes the tight adherence characteristic of EPEC ?

A

EPEC adherence factor (EAF)

and the chromosomal locus of enterocyte effacement (LEE) pathogenicity island

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32
Q

What is the “effacement” of EPEC ?

A

loss of microvilli
formation of filamentous actin pedestals or cup-like structures

occasionally, entry of the EPEC into the mucosal cells

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33
Q

What are the two clinical syndromes associated with ETEC ?

A

“weanling diarrhea” among children in tropical and subtropical
climates, especially in developing countries

“Traveler’s diarrhea” (also referred to as “Montezuma’s revenge”; “Delhi belly”)

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34
Q

Characteristics of ETEC

A

Produces a typically mild, self-limiting disease which is abrupt in onset with short incubation period

profuse watery diarrhea (similar with V. cholerae), usually without blood, mucus, or pus; accompanied by mild abdominal cramps; usually without vomiting or fever

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35
Q

How is the pathology of ETEC mediated by fimbrae ?

A

Facilitates colonization of ETEC on the proximal small intestine by binding to specific receptors on the intestinal microvilli

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36
Q

Which fragment of the heat labile toxin of ETEC activates cellular adenylate cyclase, and what does it do ?

A

A moiety (fragment)

increase in the conversion of adenosine triphosphate to cyclic adenosine monophosphate (cAMP)

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37
Q

What does the accumulation of cAMP means in ETEC ?

A

hypersecretion of both electrolytes and fluids into the intestinal lumen, resulting in watery diarrhea similar to cholera

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38
Q

Which fragment of the heat labile toxin of ETEC is known as the binding portion ?

A

B moiety (fragment)

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39
Q

Which exotoxin of ETEC stimulates guanylate cyclase ? and what does this lead to ?

A

Heat stable toxin

Increased production of cyclic guanosine monophosphate, accumulation of which also causes hypersecretion

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40
Q

How is ETEC commonly spread ?

A
  1. consumption of contaminated food or water
  2. poor hygiene, reduced availability of sources of potable water
  3. inadequate sanitation
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41
Q

How is EHEC commonly spread ?

A

Food and food products such as processed meats, unpasteurized dairy products, apple cider, bean sprouts, and spinach

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42
Q

This type of diarrheagenic E. coli is associated with colitis, and hemolytic uremic syndrome (HUS)

A

EHEC

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43
Q

Which of the EHEC’s verotoxin is a phage-encoded cytotoxin ?

A

Verotoxin I

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44
Q

Of the E. coli serotypes that produce Shiga toxin which is the most common and is the one that can be identified most readily in clinical specimens ?

A

O157:H7

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45
Q

How is EIEC transmitted from one person to another ?

A

Direct transmission from person to person via the fecal-oral route has been reported

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46
Q

Characteristics of EIEC

A

fever, colitis, severe abdominal cramps (tenesmus), malaise, and watery diarrhea with blood, mucus and leukocytes in stool

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47
Q

Characteristics of EHEC

A

Produces a watery diarrhea that progresses to bloody
diarrhea with abdominal cramps and low-grade fever or an absence of fever but the stool does not contain
leukocytes

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48
Q

This diarrheagenic E. coli adheres to epithelial cells in a pattern resembling a pile of stacked bricks

A

EAEC

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49
Q

Characteristics of EAEC

A

watery, mucoid diarrhea with low grade fever and little or no vomiting, white blood cells and red blood cells are typically absent from the stool

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50
Q

EAEC pathology has been associated with what factors ?

A

St-like toxin, LT toxin, and fibril colonization factors called “AAFs” (aggregative adherence fimbriae)

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51
Q

How can newborns be infected with E. coli ?

A
  1. infection in the birth canal just before or during delivery
  2. when the mother’s vagina is heavily colonized
  3. infection may also result if contamination of the amniotic fluid occurs
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52
Q

How are newborns highly susceptible to E. coli ?

A

They lack in IgM antibodies

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53
Q

What coliform is also known as Friedlander’s bacillus

A

Klebsiella

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54
Q

What is the most commonly isolated klebsiella species ?

A

Klebsiella pneumoniae

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55
Q

Describe the sputum produced by klebsiella pnuemoniae

A

thick, mucoid, and brick red, or thin and “currant jelly-like” in appearance

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56
Q

Characteristics of Klebsiella pneumoniae

A

Also produces urinary tract infection, wound infections, meningitis, bacteremia with focal lesions (e.g., lives abscesses) in debilitated patients

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57
Q

Which klebsiella specie has their pathology associated with a large polysaccharide capsule that confers protection against phagocytosis and antimicrobial absorption ?

A

Klebsiella pneumoniae

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58
Q

Isolates of this Klebsiella specie have also been linked to antibiotic/antimicrobial-associated hemorrhagic colitis (AAHC)

A

Klebsiella oxytoca

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59
Q

What is AAHC ?

A

a distinct form of antibiotic-associated diarrhea, in which C. difficile is absent and where patients experience a sudden onset of bloody diarrhea often in combination with severe abdominal cramps

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60
Q

Klebsiella specie that has been isolated from cerebral abscesses and nasal mucosa in ozena

A

Klebsiella pneumoniae subspecies ozaenae

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61
Q

Klebsiella specie that has been isolated from patients with rhinoscleroma

A

Klebsiella pneumoniae subspecies rhinoscleromatis

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62
Q

Klebsiella specie that causes granulomatis inguinale

A

Klebsiella granulomatis

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63
Q

Difference between klebsiella and enterobacter species ?

A

Eneterobacter is motile

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64
Q

What are the two most common isolates from the Enterobacter species ?

A

Enterobacter cloacae and Enterobacter (now Klebsiella) aerogenes

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65
Q

Clinical relations to Enterobacter cloacae and Enterobacter (now Klebsiella) aerogenes

A

Causes a broad range of hospital-acquired infections

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66
Q

Enterobacter isolate that come from diverse geographic and ecologic sources

A

Enterobacter (now Pantoea) agglomerans

67
Q

Which enterobacter specie was responsible for an outbreak of septicemia caused by contaminated
intravenous fluids ?

A

Enterobacter (now Pantoea) agglomerans

68
Q

This Enterobacter specie typically produces a yellow pigment and is sometimes referred to as yellow-pigmented E. cloacae

A

Enterobacter (now Cronobacter) sakazakii

69
Q

This Enterobacter specie is associated with contaminated powdered infant formula and has also been isolated from cultures taken from brain
abscesses and respiratory and wound infections

A

Enterobacter (now Cronobacter) sakazakii

70
Q

Where is Enterobacter gergoviae usually isolated from ?

A

Has been found in respiratory samples and is rarely isolated from blood cultures.

71
Q

Where is Enterobacter hormaechei usually isolated from ?

A

human sources such as blood, wounds, and sputum

72
Q

Which coliform Enterobacteriaceae has been earlier classified within the tribe Salmonelleae ?

A

Citrobacter species

73
Q

What medium can Citrobacter species grow on ?

A

Simmons citrate medium

74
Q

Where is Citrobacter freundii isolated from ?

A

known as an extra intestinal pathogen, it can also be

isolated in stool cultures

75
Q

Other than UTI what other infections can arise from Citrobacter freundii ?

A

nosocomial infectious diseases including pneumonias, and intraabdominal abscesses as well as endocarditis in intravenous drug abusers

76
Q

What is clinically significant with Citrobacter koseri ?

A

pathogen documented as the cause of nursery outbreaks of neonatal meningitis and brain abscesses

77
Q

What are the prevention and control of coliforms ?

A

Enteropathogenic E. coli serotypes should be controlled like salmonellae

78
Q

How are proteus species normally transmitted ?

A

Within hospitals or other institutions, these bacteria commonly are transmitted by personnel, instruments, or parenteral medications.

79
Q

How is transmission of the proteus species controlled ?

A

handwashing, rigorous asepsis, sterilization of equipment, disinfection, restraint in intravenous therapy, and strict precautions in keeping the urinary tract sterile (ie, closed drainage).

80
Q

Of the proteus genus, which species are widely recognized human pathogens ?

A

P. mirabilis and P. vulgaris

81
Q

What is the correlation with Proteus species and promoting struvite kidney stone (also called calculi) formation ?

A

They produce urease resulting in rapid hydrolysis of urea with liberation of ammonia

Rapid hydrolysis of urea causes the urine to become alkaline, making acidification virtually impossible

82
Q

Name the importance of the Dienes Phenomenon ?

A

It is used to differentiate the two strains of Proteus for epidemiological purposes

83
Q

What clinical manifestations are correlated to Morganella morganii ?

A

UTI, wound infections, neonatal sepsis

84
Q

Compare Morganella morganii and the Proteus species

A

Both produce urease and are motile, but Morganella morganii does not swarm

85
Q

What clinical manifestations are correlated to P. rettgeri ?

A

pathogen of urinary tract
caused occasional outbreaks in health care settings
implicated in diarrheal disease among travelers

86
Q

What clinical manifestations are correlated to P. stuartii ?

A

outbreaks in burnt units

87
Q

Why is it difficult to treat immunocompromised patients infected with P. rettgeri and P. stuartii ?

A

Due to their resistance to antimicrobials

88
Q

What is the chief reservoir for E. tarda ?

A

reptiles and freshwater fish

89
Q

What are the clinical manifestations for E. tarda ?

A

may cause a variety of extraintestinal infections; wound infections resulting from trauma, often related to aquatic accidents

implicated in abscesses that may lead to bacteremia or myonecroses

90
Q

Name the key characteristic of E. tarda

A

production of abundant amounts of hydrogen sulfide

91
Q

What are the three hydrolytic enzymes produced by the Serratia species ?

A

Gelatinase
Lipase
DNase

92
Q

Differentiate the documented pigments produced by the Serratia species

A

Prodigiosin - the non-water-soluble, and non-diffusible pigment

Pyrimine - the water-soluble and diffusible pigment

93
Q

Which species of the genus Serratia is mostly associated with a variety of human infections ? and what are those infections ?

A

non-pigmented S. marcescens

pneumonia, bacteremia, and endocarditis, especially in narcotics addicts and hospitalized patients.

94
Q

What are the six subspecies of S. enterica ?

A

S. enterica subsp. enterica (also called subspecies I)
S. enterica subsp. salamae (subspecies II)
S. enterica subsp. arizonae (subspecies IIIa)
S. enterica subsp. diarizonae (subspecies IIIb)
S. enterica subsp. houtenae (subspecies IV)
S. enterica subsp. indica (subspecies VI)

95
Q

Which strain of S. enterica is the cause of most human illnesses ?

A

S. enterica subspecies enterica

96
Q

What are two species that comprise the genus Salmonella ?

A

S. enterica and S. bongori

97
Q

Which salmonella strains are primarily infective for humans ?

A

Salmonella Typhi
S. Choleraesuis
perhaps S. Paratyphi A and S. Paratyphi B

98
Q

How are the salmonella strains normally transmitted ?

A

oral route, usually with contaminated food or drink

99
Q

What is the mean infective dose to produce clinical or subclinical infection in humans for Salmonella ?

A

10^5 – 10^8 salmonellae

100
Q

What population is usually affected by Typhoid fever and why ?

A

occurs more often in tropical and subtropical areas

outbreaks has been associated with:
improper disposal of sewage
poor sanitation
lack of a modern potable water system

101
Q

What is the major cause of bacterial enteric illness in both humans and animals ?

A

Salmonellosis

102
Q

What are the factors responsible for the virulence of salmonellae ?

A

Fimbriae - used in adherence and in initiating
intestinal infection

The ability of salmonellae to traverse intestinal
mucosa

Enterotoxin - produced by certain Salmonella
strains that cause gastroenteritis

Vi antigen (virulence or capsular antigens) - found in some strains.

103
Q

Which Salmonella strain is most correlated to Typhoid fever ?

A

S. typhi

104
Q

What is the onset of Typhoid fever ?

A

approximately 9 to 14 days after ingestion of the organisms

depends on the number of organisms ingested — the
larger the inoculum, the shorter the incubation period.

105
Q

What symptoms do the patient develop once the S. typhi invades and penetrates the intestinal mucosa
?

A 
fever, accompanied by:
malaise
lethargy
myalgia
anorexia
a continuous dull frontal headache 
constipation instead of diarrhea
106
Q

How does S. typhi multiply once it has invaded the body ?

A

lymphatic system -> bacteria eventually reach the
bloodstream -> spread to the liver, spleen, and bone marrow

engulfed by mononuclear phagocytes — where they multiple intracellularly

107
Q

What is the significance of the second release of S. typhi into the body after intracellular multiplication ?

A

febrile episodes are more evident

organisms may be easily isolated from the blood

108
Q

When do “rose spots” appear during Typhoid fever and where ?

A

2nd week around the umbilical region

109
Q

Which organ becomes the foci of long-term carriage of S. typhi during typhoid fever ?

A

gallbladder

110
Q

What are the complications of Typhoid fever ?

A

necrosis in the gallbladder leading to necrotizing cholecystitis

necrosis of the Peyer’s patches leading to hemorrhage

perforation of the bowel

111
Q

What is Salmonella bacteremia collectively referred to as ?

A

nontyphoidal Salmonella

112
Q

Which salmonella strains is commonly associated with Salmonella bacteremia ?

A

S. choleraesuis

but may be caused by any salmonella serotype such as Typhimurium, and Paratyphi

113
Q

What are the characteristics of Salmonella bacteremia ?

A

may occur with and without extraintestinal foci of infection

prolonged fever and intermittent bacteremia

114
Q

What is the most common manifestation of salmonella infection ?

A

Enterocolitis

115
Q

Which salmonella strain is the common cause for enterocolitis ?

A

S. Typhimurium and S. Enteritidis

but can be caused by any of the more than 1400 group I serotypes of salmonellae.

116
Q

What are the characteristics of salmonella enterocolitis ?

A

Nausea, headache, vomiting, and profuse diarrhea, low grade fever

inflammatory lesions are present in the small and large intestinal mucosa and stools have few leukocytes

117
Q

What are the phases of Typhoid fever ?

A

(a) Ingested bacteria invade the intestinal lining
(b) From this site, they enter the blood stream, causing septicemia and endotoxemia
(c) Infection in the lymphatic tissue of the small intestine can produce varying degrees of ulceration and perforation of the intestinal wall

118
Q

How can the carrier state of salmonella strains be resolved ?

A

antimicrobial therapy if gallbladder infection is not evident

cholecystectomy has been the only solution to the chronic state of enteric carriers

119
Q

What are the two available typhoid vaccines in the US ?

A

oral live, attenuated vaccine and a Vi capsular polysaccharide vaccine for intramuscular use

120
Q

What is the prevention and control for typhoid ?

A

prevent contamination of food and water by rodents or other animals that excrete salmonellae

Infected poultry, meats, and eggs must be thoroughly cooked

Carriers must not be allowed to work as food handlers, strict hygiene

Vaccination is recommended for travelers to endemic regions

121
Q

What is the group, type, and other name for Shigella dysenteriae, under Ewing’s classification ?

A

A, Shiga’s bacillus / Japanese dysentery bacillus

122
Q

What is the group, type, and other name for Shigella flexneri, under Ewing’s classification ?

A

B, Flexner’s bacillus or Strong’s bacillus /Philippine dysentery bacillus

123
Q

What is the group, type, and other name for Shigella boydii, under Ewing’s classification ?

A

C, Boyd’s bacillus / British dysentery bacillus

124
Q

What is the group, type, and other name for Shigella sonnei, under Ewing’s classification ?

A

D, Sonne-Duval’s bacillus / US dysentery bacillus

125
Q

What is the reservoir for Shigella spp ?

A

Humans and large primates

126
Q

How is shigella transmitted ?

A

4F: food fingers feces and flies

direct person-to-person contact

fecal-oral route

transmitted by flies, fingers, and food or water contaminated by infected persons

127
Q

What makes shigellosis highly communicable ?

A

low infective dose (approximately less than 100 bacilli) required to produce the disease

128
Q

What is the possible cause of irritation of the bowel wall in shigellosis ?

A

Endotoxins

129
Q

What are the characteristics of Shigella dysenteriae toxin ?

A

Antigenic protein
Enterotoxin
Neurotoxin

130
Q

How does shigella dysenteriae toxin produce diarrhea ?

A

inhibits sugar and amino acid absorption in the small intestine

131
Q

What is the time of onset for symptoms of shigella species ?

A

24 - 48 hours

132
Q

What symptoms mark the onset of shigella species ?

A

high fever, chills
abdominal cramps
pain accompanied by tenesmus (rectal spasms)
watery diarrhea progresses to bloody stools containing mucus and numerous leukocytes

133
Q

What complications may arise with shigellosis ?

A

Rectal prolapse

Ileus, with marked abdominal dilation, possibly leading to toxic megacolon

134
Q

How is transmission of shigella controlled ?

A

sanitary control of water, food, and milk; sewage disposal and fly control

isolation of patients and disinfection of excreta

detection of subclinical cases and carriers, particularly food handlers

antibiotic treatment of infected individuals.

135
Q

What are the Yersinia species that can cause zoonoses in man, yersinioses ?

A

Y. pestis
Y. enterocolitica
Y. pseudotuberculosis

136
Q

How can Y. enterocolitica be transmitted ?

A

animals, including domestic swine, cats, and dogs

ingestion of contaminated food, often pork, and vacuum-packed deli meat, beef, lamb, chicken, and possibly chocolate milk and water

137
Q

What is the mean infective dose to produce clinical or subclinical infection in humans for Y. enterocolitica ?

A

10^8 – 10^9 yersiniae must enter the alimentary tract

138
Q

What is the onset process of Y. enterocolitica in relation to acute gastroenteritis ?

A

the yersiniae multiply in the gut mucosa during the incubation period of 4-7 days

This leads to inflammation and ulceration, and leukocytes appear in feces

139
Q

What clinical manifestations can arise from Y. enterocolitica ?

A

acute gastroenteritis
appendicitis-like syndrome
less frequently: septicemia, arthritis, and erythema nodosum

140
Q

What is the chief reservoir for Y. pseudotuberculosis ?

A

Rodents, particularly guinea pigs

141
Q

What is a significant characteristic of Y. pseudotuberculosis ?

A

caseous swellings called pseudotubercles

When ingested, the organisms spread to the mesenteric lymph nodes, producing a generalized infection that is usually self-limiting

142
Q

What clinical manifestations can arise from Y. pseudotuberculosis ?

A

septicemia accompanied by mesenteric lymphadenitis

143
Q

This noncoliform is also referred to as the plague bacillus

A

Y. pestis

144
Q

What is the chief reservoir of Y. pestis ?

A

rodents

145
Q

How is Y. pestis transmitted ?

A

From rodents, by bites of fleas

contact with:
wild animals (sylvatic plague)
domestic or semi domestic animals (urban plague)
infected humans

146
Q

What is the most common form of plague ?

A

Bubonic form or glandular form

147
Q

What is the onset of bubonic form of plague ?

A

2 - 5 days

148
Q

What clinical manifestations can arise from bubonic form of plague ?

A

high fever
painful, swollen, and necrotic regional lymph nodes (typically in the groin, less often in the axilla) known as buboes (s. bubo; G. boubon, the groin)

149
Q

What form of plague occurs when the bacteria spread to the bloodstream ?

A

Septicemic form

150
Q

What are the early and late manifestations of septicemic form of plague ?

A

Early manifestations:
vomiting and diarrhea
disseminated intravascular coagulation leads to hypotension
altered mental status

Later manifestations:
renal and cardiac failure

Terminally:
pneumonia and meningitis

151
Q

Scientific name of the flea used to transmit Yersina pestis ?

A

Xenopsylla cheopsis

152
Q

When does the pneumonic form of Y. pestis occur as bubonic or septicimic ?

A

When organisms proliferate in the bloodstream and respiratory tract

153
Q

Symptoms of pneumonic form of Y. pestis ?

A

fulminant course with chest pain, cough, hemoptysis, and severe respiratory distress

154
Q

True or false: Some of the yersiniae possess lipopolysaccharides that have endotoxic activity when released

A

False; all yersiniae possess…

155
Q

This factor yield the requirement for calcium for growth of the yersiniae at 37°C

A

V and W antigens

156
Q

This factor is involved in dissemination of the organism from the flea bite injection site

A

pPCP1

157
Q

In relation to the plasmid pPCP1 describe the temperature-dependent coagulase activity

A

20°–28°C, the temperature of the flea

158
Q

In relation to the plasmid pPCP1 describe the temperature-dependent fibrinolytic activity

A

35°–37°C, the temperature of the host

159
Q

How does pFra/pMT help cause diseases by Y. pestis ?

A

encodes the capsular protein (fraction F1) that is produced mainly at 37°C and confers anti-phagocytic properties

this plasmid contains genes that encodes
phospholipase D, which is required for organism survival in the flea midgut

160
Q

What is yersinibactin ?

A

A factor that allows Y. pestis to cause diseases which is encoded by a pathogenecity island (PAI), is an
iron-scavenging siderophore

161
Q

What is the prevention and control of Y. pestis related diseases ?

A

surveys of infected population

immediate notification to health authorities once infection has been diagnosed

patients with suspected plague must be isolated

162
Q

Characteristics of Plesiomonas shigelloides

A 
oxidase +
catalase + 
glucose fermenting
polar flagella
gram - rod
163
Q

What is the chief reservoir of Plesiomonas shigelloides

A

aquatic environments that are limited geographically by its minimum growth temperature of 8° C

fresh and estuarine water, usually in tropical countries

164
Q

What are the three major clinical types of gastroenteritis caused by Plesiomonas shigelloides ?

A

common watery or secretory diarrhea

subacute or chronic disease that lasts from 14 days to 2 to 3 months

invasive, dysenteric form that resembles colitis

Clinical Bacteriology Lec (2 decks)

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