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BACTE LEC > WK 5 - Entero > Flashcards

WK 5 - Entero Flashcards

1
Q

all ENTEROBACTERIACEAE are

Cytochrome oxidase negative, except

A

Plesiomonas

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2
Q

all ENTEROBACTERIACEAE are
All reduce nitrate to nitrite, except for

A

Photorhabdus and
Xenorhabdus

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3
Q

all ENTEROBACTERIACEAE are
All are motile at body temperature, except for

A

Klebsiella, Shigella, and Yersinia

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4
Q

In ENTEROBACTERIACEAE,

None has remarkable colony morphology on supportive
media, appearing large, moist, and gray on SBA, CHOC,
and most non-selective media;

A

except Klebsiella, Proteus,
and some Enterobacter species

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5
Q

characteristics of entero

A
  • Often referred as enterics
  • Gram-negative bacilli/coccobacilli
  • Non-spore forming, facultatively anaerobic bacilli
  • Cytochrome oxidase negative, except Plesiomonas
  • All are glucose-fermenting
  • All reduce nitrate to nitrite, except for Photorhabdus and
    Xenorhabdus
  • All are motile at body temperature, except for
    Klebsiella, Shigella, and Yersinia
  • None has remarkable colony morphology on supportive
    media, appearing large, moist, and gray on SBA, CHOC,
    and most non-selective media; except Klebsiella, Proteus,
    and some Enterobacter species
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6
Q

what media should be used for entero

A
  • Colony morphology on non-selective media, such as SBA
    and CHOC are of little value in their identification
  • A wide variety of differential and selective media such as
    MAC and EMB (Eosine Methylene Blue), highly selective media such as HE and XLD are available for presumptive identification of enteric pathogens
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7
Q

what does entero ferment

A

lactose and sucrose

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8
Q

Species that produce H2S may be readily distinguished
when placed on

A

HE or XLD agar

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9
Q

_______ contain _____________ which produce
blackening of H2S-producing colonies

A

HE and XLD agars contain sodium thiosulfate and
ferric ammonium citrate, which produce
blackening of H2S-producing colonies

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10
Q

can
inactivate extended-spectrum cephalosporins (e.g.,
cefotaxime), penicillins, and aztreonam

A

plasmid-mediated
extended-spectrum β-lactamases (ESBLs)

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11
Q

Increasing numbers of ______________ clinical strains produce plasmid-mediated
extended-spectrum β-lactamases (ESBLs)

A

Increasing numbers of E. coli, K. pneumoniae, and K.
oxytoca clinical strains produce plasmid-mediated
extended-spectrum β-lactamases (ESBLs)

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12
Q

Antigens used in the identification of different serologic
groups

A

o O antigen (somatic) – heat-stable, located on the cell
wall
o H antigen (flagellar) – heat-labile, surface of flagella,
responsible for motility
o K antigen (capsular) – heat–labile polysaccharide
found only in certain encapsulated species
o K1 antigen of E. coli
o Vi antigen of Salmonella enterica subsp. enterica
serotype Typhi

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13
Q

Most enteric reside in the GI tract except for

A

Salmonella,
Shigella, and Yersinia

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14
Q

Initially considered a harmless member of colon resident
biota

A

e coli

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15
Q

Primary marker of fecal contamination in water
purification or water quality testing

A

e coli

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16
Q

vf of e coli

A

Most strains are motile and generally possess adhesive
fimbriae and sex pili, and O, H, & K antigens

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17
Q

is often useful in
identification of strains, particularly those associated with
serious enteric disease

A

Serotyping for O and H antigens

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18
Q

often masks the O antigen during bacterial
agglutination testing with specific antiserum

A

K antigen

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19
Q

– identical to capsular antigen found in
Neisseria meningitides group B

A

K1 antigen

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20
Q

how does e coli appear in agar

A
  • Appears as a lactose-positive (pink) colony with a
    surrounding area of precipitated bile salts on MAC agar
  • Appears with a green metallic sheen on EMB agar with the
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21
Q

propoerties of e coli in emb agar

A

following properties:

o Glucose, lactose, trehalose, and xylose fermentation

o Indole production from tryptophan

o Glucose fermentation by mixed acid pathway:

o methyl red positive, Voges-Proskauer negative

o Does not produce H2S, DNase, Urease or
phenylalanine deaminase

o Can’t use citrase as sole carbon source

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22
Q
  • Most common cause of UTI in humans
A

Uropathogenic E. Coli

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23
Q

Causes acute pyelonephritis in immunocompetent hosts
are dominant resident in colon

A

Uropathogenic E. Coli

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24
Q

Uropathogenic E. Coli
vf

A
  • Resistant to antibacterial activity of human serum
  • Pili – adhesion to epithelial cells - Cytolysins (hemolysins) – kill immune factor
    cells and inhibit phagocytosis and chemotaxis of
    certain WBCs - Aerobactin – chelates iron
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25
Q

kill immune factor
cells and inhibit phagocytosis and chemotaxis of
certain WBCs

A

Cytolysins (hemolysins)

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26
Q

Associated with diarrhea of infants and adults in tropical
and subtropical climates, especially in developing
countries

A

Enterotoxigenic E. coli (ETEC)

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27
Q
  • Major causes of infant bacterial diarrhea
A

Enterotoxigenic E. coli (ETEC)

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28
Q

etec

A
  • High infective dose (106-1010 organisms) to initiate
    disease in an immunocompetent host
  • Stomach acidity inhibits colonization and initiation of
    disease
  • Colonization on proximal small intestine is mediated by
    fimbriae that permits binding on intestinal microvilli
  • Heat-labile toxin (LT) – similar in action and amino acid
    sequence to cholera toxin from V. cholera
  • LT fragment A – enzymatically active portion
  • Lt fragment B – moiety, binding portion, confers specificity, binds to the mucosa and providing entry for A portion
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29
Q

detect ETEC in
fecal specimens

A

Enzyme-labeled oligonucleotide probes

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30
Q

Produce dysentery with direct penetration, invasion,
and destruction of the intestinal mucosa

A

Enteroinvasive E. coli (EIEC)

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31
Q

Diarrheal illness is similar to that of Shigella spp.
although infective dose of EIEC is much higher

A

eiec

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32
Q

entericthat cause Fever, severe abdominal cramps, malaise, and watery
diarrhea

A

eiec

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33
Q

eiec

A
  • Strains can be non-motile and generally don’t ferment
    glucose
  • Don’t decarboxylate lysine
  • Sereny test – ability to produce keratoconjunctivitis in the
    guinea pig
  • It is also possible to detect invasiveness using monolayer
    cell cultures with HEp-2 cells (human epithelial-2 cells)
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34
Q
  • Causes infantile diarrhea
A

Enteropathogenic E. coli (EPEC)

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35
Q

epec

A
  • Adhesive property
  • Only certain H antigenic types within each O serogroup are
    connected to intestinal infections
  • O serogrouping can’t differentiate this E. coli strain from strains of normal biota
  • Low-grade fever, malaise, vomiting, diarrhea
  • Stool contains mucus, no blood present
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36
Q
  • identify EPEC
A

Serologic typing with pooled antisera

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37
Q

strain associated with hemorrhagic diarrhea,
colitis, and hemolytic uremic syndrome (HUS)

A

O157:H7 eec

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38
Q

eec

A
  • Stool has NO leukocytes
  • HUS is characterized by low platelet count, hemolytic
    anemia, and kidney failure
  • Watery diarrhea that progresses to bloody diarrhea
    with abdominal cramps, low-grade fever or absence of
    fever, no WBCs, distinguishing it from dysentery caused by
    Shigella spp. or EIEC infections
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39
Q

biologically similar to, immunologically
different from, both Stx and verotoxin I. Not neutralized
by antibody to Stx

A

verotoxin ii

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39
Q

Verotoxin I

A

phage-encoded cytotoxin identical to
Shiga toxin (Stx) produced by S. dysenteriae type I

  • Produces damage to Vero cells(African green
    monkey kidney cells)
  • Reacts with and is neutralized by the antibody
    against Stx
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40
Q

Verotoxin producing E. coli may be identified by one of
three methods

A

o Stool culture on highly different medium, with subsequent
serotyping
o Detecting verotoxin in stool filtrates
o Demonstration of a fourfold or greater increase in verotoxin
neutralizing antibody titer

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41
Q

verotoxin is associated with

A

eec

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42
Q

Stool culture for O157:H7 may be performed using

A

MAC
agar containing sorbitol (SMAC) instead of lactose.
O157:H7 does not ferment sorbitol in 48 hours, and
appears colorle

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43
Q

Generally associated with two kinds of human disease:
diarrheal syndromes and UTIs

A

Enteroadherent E. coli (EAEC)

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44
Q
  • Two types of EAEC
A

o DAEC

– associated with both UTIs and diarrheal
disease

  • Uropathogenic strains are closely associated with
    cystitis in children and acute pyelonephritis in
    pregnant women
  • Chronic or recurring UTI

o EAEC

– causes diarrhea by adhering to the surface
of the intestinal mucosa

  • Adheres to HEp2 cells, packed in an aggregative
    “stacked-brick” pattern on the cells and between
    the cells by means of fimbriae
  • Watery diarrhea, vomiting, dehydration,
    occasional abdominal pain, mostly in children
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45
Q

extraintestinal infection of e coli

A
  • Newborn usually acquires infection in the birth canal just
    before or during delivery, when the mother’s vagina is
    heavily colonized. Infection may also result if contamination
    of the amniotic fluid takes place
  • Septicemia and meningitis
  • Capsular antigen K1 is the most documented virulence
    factor associated with neonatal meningeal infections
  • E. coli bacteremia in adults may result primarily from a
    urogenital tract infection or from a GI source
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46
Q

Other Escherichia Species

A
  • E. hermanii (formerly E. coli atypical/enteric group II) –
    yellow-pigmented organism isolated from CSF, wounds,
    and blood
  • E. vulneris – infected wounds, more than half the strains
    also produce yellow colonies
  • E. albertii – diarrheal disease in children
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47
Q

Usually found in the intestinal tract of humans and animals
or free-living in soil, water, and on plants

A

KLEBSIELLA

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48
Q

Associated with a number of opportunistic and nosocomial
infections (e.g. pneumonia, wound, UTI)

A

KLEBSIELLA

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49
Q

KLEBSIELLA

A
  • Most grow on Simmons citrate and in potassium cyanide broth
  • None produce H2S
  • Few hydrolyze urea slowly
  • Negative reaction with methyl red test
  • Positive reaction with Voges-Proskauer test
  • With few exceptions, indole is not produced from tryptophan
  • Motility varies
  • Hospital acquired outbreaks of Klebsiella resistant to
    multiple antimicrobial agents (due to plasmid transfers)
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50
Q

K. pneumoniae

A
  • Most commonly isolated species
  • Distinct feature of possessing a polysaccharide capsule,
    protecting against phagocytosis and antimicrobial
    absorption, also responsible for moist, mucoid colony
    appearance
  • Capsule is sometimes helpful in providing presumptive
    identification
  • Colonization in respiratory tracts of hospitalized patients
    increases with the length of stay
  • Frequent cause of lower respiratory tract infections among hospitalized patients and in immunocompromised hosts
  • Antimicrobial resistance is most severe with K. pneumoniae
    because of presence of K. pneumoniae carbapenemase
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51
Q

k neumoniae can also cause

A
  • Wound infections, UTIs, bacteremia, liver abscesses
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52
Q

Identical to K. pneumoniae except for its production of
indole and ornithine-positive isolates

A

K. oxytoca

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53
Q

K. pneumoniae subsp. ozenae

A
  • Isolated from nasal secretions and cerebral abscesses
  • Causes atrophic rhinitis
  • Highly associated with the presence of plasmid mediated
    ESBLs, contributing to large numbers of nosocomial
    infections seen today
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54
Q

K. pneumoniae subsp. rhinoscleromatis

A

Isolates from patients with rhinoscleroma, an infection of
the nasal cavity, manifesting as an intense swelling and
malformation of the entire face and neck

55
Q

K. ornithinolytica (Raoultella)

A
  • Indole positive
  • Ornithine decarboxylase positive
  • Isolated from urine, respiratory tracts, and blood along with
    K. planticola
56
Q

K. planticola (Raoultella)

A
  • Isolated from urine, respiratory tracts, and blood
  • Difficult to distinguish from K. pneumoniae
57
Q
  • Isolated from sterile sites
A

K. variicola

58
Q

ENTEROBACTER, CRONOBACTER, PANTOEA

A

*motile

  • Enterobacter – composed of 12 species
  • Colony morphology resembles that of Klebsiella when
    growing on MAC
  • Grow on Simmons citrate medium and in potassium
    cyanide broth
  • Methyl red = negative
  • Voges-Proskauer = positive
  • Usually produce ornithine decarboxylase, unlike
    Klebsiella
  • Lysine decarboxylase is produced by most species but not by E. gergoviae or E. cloacae
59
Q

o Most common isolates
o Wounds, urine, blood, CSF

in enteric

A
  • E. cloacae and E. aerogenes
60
Q

Gained notoriety with a nationwide outbreak of
septicemia resulting from contaminated IV fluids

A

Pantoea agglomerans

61
Q

Includes species that are lysine, ornitihine, and arginine
negative or “triple decarboxylases negative”

A

Pantoea agglomerans

62
Q

Pantoea agglomerans HG XII

A
  • May produce a yellow pigment
  • Primarily a plant pathogen
63
Q

Found in respiratory samples and is rarely isolated from
blood cultures

A

E. gergoviae

64
Q

Cronobacter sakazaki

A
  • Typically produces a yellow pigment
  • Pathogen in neonates causing meningitis and bacteremia,
    often coming from powdered infant formula
  • Isolated from cultures taken from brain abscesses and
    respiratory wound infections
65
Q
  • Isolated from blood, wounds, and sputum
A

E. hormaechei

66
Q

E. asburiae

A
  • Biochemically similar to E. cloacae
  • Isolated from blood, urine, feces, sputum, and wounds
67
Q
  • Associated with osteomyelitis following traumatic wounds
A

E. cancerogenus (formerly E. taylorae)

68
Q

E.dissolvens and E. nimipressuralis

A
  • Newly recognized species with unknown clinical
    significance
69
Q

SERRATIA

A
  • Opportunistic pathogens associated with nosocomial
    outbreaks
  • Ferments lactose slowly and positive for orthonitrophenyl galactoside (ONPG) test, except S. fonticola
  • Differentiate from other members of the tribe by their
    ability to produce extracellular DNase
  • Resistance to a wide range of antimicrobials
70
Q
  • Ferments lactose slowly and positive for orthonitrophenyl galactoside (ONPG) test, except

serratia

A

S. fonticuli

71
Q

Often produce pink to red pigment, prodigiosin, especially
when isolates are incubated at room temperature

A

S. marcescens, S. rubidaea, S. plymuthica

72
Q

most clniicaly sig serratia

A
  • S. marcescens is the most clinically significant
73
Q

Frequently found in nosocomial infections of the urinary
and respiratory tract and in bacteremia outbreaks in
nurseries and cardiac surgery and burn units

A

serattia

74
Q

Contamination of antiseptic solution used for joint injections
has resulted in an epidemic of septic arthritis

A

serattia

75
Q

S. odorifera

A
  • Contains two biogroups
  • Emits a dirty, musty odor resembling that of potatoes

o Biogroup 1 – isolated predominantly from respiratory
tract and is positive for sucrose, raffinose, and
ornithine, may be indole positive (60%)

o Biogroup 2 – negative for sucrose, raffinose and
ornithine and has been isolated from blood and CSF,
may also be indole positive (50%)

76
Q

Isolated from a number of anatomic sites in humans and in
the environment

A

HAFNIA

77
Q

grows in the beer wort of breweries
and has not been isolated clinicallyE

A

H. alvei biotype 1

78
Q

Delayed positive citrate reaction is a major
characteristic

A

HAFNIA

79
Q

Not known to cause gastroenteritis but is occasionally
isolated from stool cultures

A

HAFNIA

80
Q

distinguished from other members of
Enterobacteriaceae by virtue of the ability to deaminate
phenylalanine

A

Tribe Proteeae

81
Q

does proteus ferment lactose

A

noooo

82
Q

proteus spp

A
  • Four species: P. mirabilis, P. vulgaris, P. penneri and P.
    myxofaciens
  • P. mirabilis and P. vulgaris – human pathogens
83
Q

Ascend the urinary tract, causing infections in both lower
and upper urinary tract

A

proteus

84
Q

Can infect proximal kidney tubules and can cause acute
glomerulonephritis, particularly patients with urinary tract
defects or catheterization

A

proteus

85
Q

Produce “swarming” colonies on nonselective media
such as SBA

A

P. mirabilis and P.vulgaris

86
Q

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

A

Swarming

P. mirabilis and P.vulgaris

87
Q

Swarmer cells produce distinct odor described as “burnt
chocolate” and plays a role in the ascending nature of
Proteus-associated UTIs

A

P. mirabilis and P.vulgaris

88
Q

proteus characteristics

A
  • Produces H2S and hydrolyzes urea
  • P. mirabilis doesn’t produce indole from tryptophan and is
    ornithine positive
  • P. vulgaris produces indole and is ornithine negative, and
    ferments sucrose, therefore giving an acid/acid reaction
    in TSI agar (triple sugar iron agar)
89
Q

P. penneri

A
  • Can also swarm on nonselective media
  • Isolated from patients with diarrhea, although the role of
    organism in disease hasn’t been proven
90
Q

P. myxofaciens

A
  • Isolated only from gypsy moths
  • Large amount of slime it produces
91
Q

morganella

A
  • A documented cause of UTI and has been isolated from
    other human body sites
  • Neither species have been implicated in diarrheal illness

two subspecies
o M. morganii subsp. morganii
o M. morganii subsp. Sibonii

92
Q

P. rettgeri

A
  • Documented pathogen of the urinary tract and has
    caused occasional nosocomial outbreaks
  • Implicated in diarrheal disease among travelers
93
Q

P. stuartii

A
  • Implicated in nosocomial outbreaks in burn units and has
    been isolated from urine cultures
  • Infections caused by P. rettgeri and P. stuartii, especially
    in immunocompromised patients, are particularly difficult
    to treat because of their resistance to antimicrobials
94
Q

P. alcalifaciens

A
  • Most commonly found in feces of children with diarrhea
  • Role as cause of diarrhea hasn’t been proven
  • Formerly identified as a strain of P. alcalifaciens
95
Q

p rustgiani

A

Rarely isolated
* Pathogenicity also remains unproven

96
Q

P. heimbachae

A
  • Yet to be isolated from any clinical specimens
97
Q

edwardsiella

A
  • Negative for urea
  • Positive for lysine decarboxylase, H2S, and indole
  • Don’t grow on Simmons citrate
98
Q

e. tarda

A
  • Only recognized human pathogen
  • Opportunist, causing bacteremia and wound infections
  • Pathogenic role in cases of diarrhea remains controversial
99
Q

e. hoshinae

A
  • Isolated from snakes, birds, and water
100
Q

e. ictalurid

A
  • Causes enteric septicemia in fish
101
Q

ERWINIA AND PECTOBACTERIUM

A
  • Plant pathogens
  • Not significant in human infections
  • Erwinia grows poorly at body temperature and fails to grow
    in selective media such as EMB and MAC
  • Identification is more for academic interest than evaluation
    of their significance as causative agents of infection
102
Q

CITROBACTER

A
  • Most hydrolyze urea slowly and ferment lactose,
    producing colonies on MAC agar that resemble those of E.
    coli
  • All grow on Simmons citrate medium and give positive
    reactions in the methyl red test
103
Q

C. freundii

A
  • Isolated in diarrheal stool cultures
  • Pathogenic role remains unestablished
  • Associated with infectious diseases acquired in hospital
    settings
  • UTI, pneumonias, intra-abdominal abcesses have been
    reported
  • Associated with endocarditis in IV drug abusers
  • Most (70%) hydrolyze urea, but all fail to decarboxylase
    lysine, whereas Salmonella fails to hydrolyze urea and most
    isolates decarboxylate lysine
  • Pathogen documented as the cause of nursery
    outbreaks of neonatal meningitis and brain abscesses
104
Q

how to diff c freundi from salmonella

A
  • Because most (80%) C. freundii produce H2S, and some strains (50%) fail to ferment lactose, the colony morphology
    on primary selective media can be easily mistaken for that
    of Salmonella when isolated from stool cultures
  • Differentiation can be done through urea hydrolysis and
    lysine decarboxylase

c freundi most (70%) hydrolyze urea, but all fail to decarboxylase
lysine, whereas Salmonella fails to hydrolyze urea and most
isolates decarboxylate lysine

105
Q

C. koseri

A

Frequently found in feces, but no evidence has been found
that it is a causative agent of diarrhea

106
Q

C. amalonaticus

A

Isolated from sites of extraintestinal infections, such as
blood and wounds

107
Q

Humans acquire the infection by ingesting the
organisms in contaminated animal food products or
insufficiently cooked poultry, milk, eggs and dairy
products

A

salmonella

108
Q

inhabit gi tract of animals

A

salmonella

109
Q

shigella

A

o Human carriers
o No animal reservoir
o Shigella dysentery usually indicates improper sanitary
conditions and poor personal hygiene

110
Q

o Transmitted by wild and domestic animals

A

yersinia

111
Q

Infections range from GI disease to mediastinal
lymphadenitis and fulminant septicemia and
pneumonia

A

shigella

112
Q

salmonella

A
  • Gram-negative, facultatively anaerobic bacilli that
    morphologically resemble other enteric bacteria
  • On selective and differential media used primarily to isolate
    enteric pathogens (e.g. MAC), salmonellae produce clear,
    colorless, non-lactose fermenting colonies
  • Colonies with black centers are seen if the media (e.g. HE
    or XLD) contain indicators for H2S production
  • In almost every case, they don’t ferment lactose
113
Q

salmonella vf

A

o Still remains uncertain
o Fimbriated strains appear more virulent than
nonfimbriated stains
o Ability to traverse intestinal mucosa
o Enterotoxin produced by certain strains that cause
gastroenteritis is a significant virulence factor.

114
Q

salmonella antigen structure

A

o Somatic O antigens and flagellar H antigens are the
primary antigenic structures used in serologic grouping
of Salmonellae
o Few strains may possess capsular K antigens,
designated Vi antigen
o Serologic identification of Vi antigen is important in
identifying Salmonella serotype Typhi
o Heat-stable O antigen of salmonella is the
liposaccharide (LPS) located in the outer membrane of
the cell wall.

115
Q

a surface polysaccharide capsular
antigen found in Salmonella serotype Typhi and a few
strains of Salmonella serotype Choleraesuis

A

Heat-labile Vi antigen

116
Q

often blocks the O antigen during serologic
typing but may be removed by heating

A

Vi antigen

117
Q

2 phase of h antigen in salmonella

A

H antigens occur in one of two phases:

o Phase 1 flagellar antigens occur only in a small
number of serotype and determine the immunologic
identity of the particular serotype: agglutinate only with
homologous antisera

o Phase 2 flagellar antigens occur among several
strains; reacts with heterologous antisera

118
Q

, also referred to as food
poisoning, occurs when a sufficient number of
organisms contaminate food that is maintained underinadequate refrigeration, thus allowing growth and
multiplication of the organisms.

most are zself limiting

A

salmonella gastroenteritis is

119
Q

The antimicrobials of choice for salmonella include

A

chloramphenicol,
ampicillin, and trimethoprim-sulfamethoxazole

120
Q

typhoid and enteric fever is caused by

A

Typhoid fever, most severe of enteric fever, caused by
Salmonella serotype Typhi; and enteric fevers caused by
other Salmonella serotypes (e.g. Salmonella Paratyphi
and Choleraesuis)

121
Q

disease caysed by salmonella

A

o Prolonged fever
o Bacteremia
o Involvement of the reticuloendothelial system
o Dissemination to multiple organs
o A febrile disease

122
Q

whatcauses typhoid fever

A

Improper disposal of sewage, poor sanitation, and lack
of a modern water system have caused outbreaks of
typhoid fever when the organisms reach a water
source.

123
Q

With the exception of ______ salmonellae organisms infect various animals
that serve as reservoirs and sources of human infections

A

With the exception of Salmonella Typhi and Salmonella
Paratyphi, salmonellae organisms infect various animals
that serve as reservoirs and sources of human infections

124
Q

causes parathypoid fever

A

Salmonella serotypes Paratyphi A, B,
and C, and Salmonella serotype Cholerasuis

125
Q

“Rose spots” (blanching, rose-colored papules around
the periumbilical region) appear during the second
week of fever

A

parathyphoid fever

126
Q

was responsible for a
nationwide outbreak linked to peanut buttercontaining
products

A

Salmonella Typhimurium

127
Q

symptoms of gastroenteritis

A

o Nausea, vomiting, fever, chills, watery diarrhea and
abdominal pain
o Symptoms usually appear within a few days, with few
or no complications

128
Q

With and without extraintestinal foci of infection caused
by nontyphoidal Salmonella, is characterized primarily
by prolonged fever and intermittent bacteremia

A
  • Nontyphoidal Bacteremia
129
Q

nonthypoidal bacteremia (serotype and treatment)

A

Serotypes most commonly associated are
Typhimurium, Paratyphi, and Cholerasuis

o May be terminated by antimicrobial therapy if
gallbladder infection is not evident
o Cholecystectomy might be a solution

130
Q

nonthypoidal bacteremia in adults and kids

A

o Young children – experience fever and gastroenteritis
with brief episodes of bacteremia
o Adults – experience transient bacteremia during
episodes of gastroenteritis or develop symptoms of
septicemia without gastroenteritis

131
Q

shigella

A
  • Not members of normal GI microbiota and can cause
    bacillary dysentery
  • S. dysenteriae
  • Cause bacillary dysentery
  • Presence of blood, mucus, and pus in stool 1
132
Q

shigella characteristics

A
  • Non-motile
  • Except for certain types of S. flexneri, they do not
    produce gas from glucose
  • Urease negative – do not hydrolyze urea
  • H2S negative – do not produce hydrogen sulfide
  • No lysine decarboxylation – do not decarboxylate lysine
  • Unlike Escherichia spp., Shigella spp. do not utilize
    acetate or mucate as carbon source
  • Fragile organism
133
Q

s sonnei characterisics

A

o Decarboxylates ornithine
o Slowly ferments lactose – delayed positive
fermentation of lactose with formation of pink
colonies only after 48 hours of incubation
o ONPG positive

134
Q
A

BACTE LEC (7 decks)

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