enterobacteriaceae + CHOLERA Flashcards
(108 cards)
1
Q
● Enterics
● Gram-negative bacilli
● Facultative anaerobes
A
enterobacteriaceae
2
Q
All species ferment glucose with the product of acid or acid and gas
A
enterobacteriaceae
3
Q
All are motiles at 35
oC with peritrichous flagella
A
enterobacteriaceae
4
Q
order enterobacterales do not produce cytochrome oxidase except _____
A
plesiomonas
5
Q
order enterobacterales reduce nitrate to nitrite except
A
photorhabdus and xenorrhabdus
6
Q
Catalase positive
- except for ___ type 1, which is
catalase-negative
A
Shigella dysenteriae
7
Q
Oxidase negative
- except for ___
A
Plesiomonas
8
Q
Non encapsulated
- except for ___ and ____
A
Klebsiella and Enterobacter
9
Q
Reduce nitrate to nitrites
- except for ____ and ___
A
Photorhabdus and Xenorrhabdus
10
Q
Most are commensal of the GI tract
- except for 3
A
Plesiomonas, Salmonella, Shigella,
and Yersinia
11
Q
may grow at 1
oC to 5 oC
A
Serratia and Yersinia
12
Q
They do not produce cytochrome oxidase
- except for
A
Plesiomonas
13
Q
e, coli,
citrobacter,
klebciella
enterobacter
A
lactose fermenter
14
Q
salmonella,
shigella,
proteus,
yersinia
A
non lactone fermenter
15
Q
most imoortant media for lf and nonlf
A
- MacConkey agar
- Eosin Methylene Blue (EMB) agar
- Salmonella Shigella (SS) agar
- Triple Sugar Iron (TSI) agar
16
Q
The most important media used to
differentiate these two classifications is the
___, with a pink colony
appearance when lactose is fermented and a
colorless colony appearance in non-lactose
fermenting organisms.
A
MacConkey agar
17
Q
– this is a heat-stable
antigen located on the cell wall.
A
O antigen (somatic antigen)
18
Q
this is a heat-labile
antigen found on the surface of flagella, structures
responsible for motility.
A
● H antigen (flagellar antigen)
19
Q
– this this is a
heat-labile polysaccharide found only in certain
encapsulated species
A
K antigen (capsular antigen)
20
Q
indicator for TSI or triple sugar iron agar
A
phenol red
21
Q
TSI = ALK/ALK or K/K, color red tube slant and butt means?
A
no fermentation
22
Q
Alkaline slant/acid butt or K/A, red/yellow
A
an indicative of glucose
fermentation only.
23
Q
Acid/acid, Yellow/Yellow, A/A
A
. Lactose (or sucrose or both) fermentation
24
Q
blackening of the medium
- Blackening of the medium occurs in the
presence of H2S or hydrogen sulfide
A
H2S production
25
formation of bubbles or splitting of the medium
from the bottom of the tube
- Bubbles or splitting in the agar indicates a
production of gas.
Gas production (aerogenic) or no gas
production (nonaerogenic)
26
IMViC reactions are a set of four useful reactions
what does IMVic stands for
● Indole Test
● Methyl Red Test
● Voges-Proskauer Test
● Citrate Utilization Test
27
Tryptophan
Indole reacts with the aldehyde in the reagent to give a red color reaction. An alcoholic layer concentrates the red color as a red ring at the top.
INDOLE TEST
28
red color after addition of
MR pH indicator
METHYL RED TEST
29
It measure the production of ACETOIN after the addition of α-naphthol (catalyst or color
intensifier) followed by 40% KOH or NaOH
● Acetoin then oxidized into diacetyl
2,3-Butanediol
● Positive reaction – red complex
VOGES-PROSKAUER TEST
30
It determines whether an organism can use
sodium citrate as a sole carbon source
● Medium used – Simmons’ Citrate Medium
(SCA) – routinely used
CITRATE UTILIZATION TEST
31
are the nitrogen source in
the medium and utilization of these salts
results in the release of ammonia, causing a
pH change for citrate utilization test
Ammonium salts
32
pH indicator for citrate utilization test, with a blue positive result
bromothymol blue
33
Determines whether an organism has the ability to
reduce nitrate to nitrite
positive reaction turns red
Nitrate Reduction Test
34
Differentiates Enterobacteriaceae (oxidase-negative) from pleisiomonas (oxidase-positive)
Oxidase Test
35
Determines the presence of the cytochrome oxidase
system that oxidizes reduced cytochrome with molecular
oxygen
Positive reaction - purple or lavender color
Oxidase Test
36
Determines whether a microorganism can hydrolyze
urea (by the action of urease enzyme), releasing a
sufficient amount of ammonia to produce a color change
by a pH indicator
Urease Test
37
pH indicator for urease test
- phenol red
38
Positive reaction for urease test
pink color
39
urease test primarily distinguisded genus__ from other enteric bacteria
proteus
40
indicator for h2s, hydrogen sulfide production
ferrous sulfate
41
lysine positive
salmonella
42
lysine negative
citrobacter
43
pH indicator for LIA
bromocresol purple
44
lysine deamination results to a what color slant?
red slant R/x
45
lysine decarboxylation results to a what color but ?
purple butt x/K
46
negative in decarb positive in deamine
R/A
47
positive both
K/R
48
, the most significant species in the
genus Escherichia
● E. coli
49
Strain of E. coli that is considered as the most
common cause of UTIs in humans
Uropathogenic E. coli (UPEC)
50
Associated with diarrhea of adults and especially children in tropical and subtropical climates
● It is the most common cause of diarrheal disease
Enterotoxigenic E. coli
51
“traveler’s diarrhea”
Enterotoxigenic E. coli
52
Produce a heat-stable toxin (ST) or a heat-labile toxin (LT) or both
Enterotoxigenic E. coli
53
Causes “infantile diarrhea”
Enteropathogenic E. coli
54
Stool contains large amount of mucus, no blood present
Enteropathogenic E. coli
55
Produce dysentery with direct penetration, invasion, and destruction of the intestinal mucosa
Enteroinvasive E. col
56
Enterohemorrhagic E. coli
Associated with hemorrhagic diarrhea and HUS (hemolytic uremic syndrome)
57
Watery diarrhea - Bloody diarrhea with abdominal
cramps, low grade fever or an absence of fever
Enterohemorrhagic E. coli
58
Processed meats (undercooked hamburgers),
unpasteurized dairy products, apple cider, bean sprouts
and spinach, all have been implicated in the spread of
infection
Enterohemorrhagic E. coli
59
Shiga-like toxins)
Enterohemorrhagic E. coli
60
Cause of diarrhea in HIV positive patients
. EAEC Enteroaggregative E. coli
61
UTIs and diarrheal disease
- Cystitis in children and acute pyelonephritis in
pregnant women
- Chronic or recurring UTIs
DAECs Diffusely Adherent E. coli
62
virulence factor associated with
neonatal meningeal infections
K1 capsular antigen
63
All are MR- and VP+
- All give a negative reaction with the methyl red test and a positive reaction with the
Voges-Proskauer test.
KLEBSIELLA
64
The absence of motility distinguishes ____
spp. from most other members of the family
Enterobacteriaceae.
Klebsiella
65
is the most commonly isolated
species and has the distinct feature of
possessing a large polysaccharide capsule.
K. pneumoniae
66
Responsible for the moist, mucoid colonies
characteristic of___ on MAC
K. pneumoniae
67
Linked to antimicrobial-associated hemorrhagic colitis
● Identical to K. pneumoniae except for its production of
indole, and there are reports of ornithine-positive isolates
as well
K. oxytoca
68
. pneumoniae subsp. ozaenae
Causes atrophic rhinitis - a tissue-destructive
disease restricted to the nose
69
an infection of the nasal
cavity that manifests as an intense swelling and
malformation of the entire face and neck
K. pneumoniae subsp. rhinoscleromatis
70
Composed of only one specie: H. alvei
hafnia
71
“Burnt chocolate” odor
● Proximal kidney tubules – A
PROTEUS
72
appearance of E.coli in EMB
characterized by a green metallic sheen
73
one of the most common causes of septicemia and meningitis among neonates, accounting for about 40% of he cases of eerly-onset meningitis
Escherichia coli
74
the E.coli that cause UTI usually originate in ____
large intestine as resident biota
75
we know that the E.coli that causes lower UTI is different in E.coli that results from catheters
E.coli strains that causes acute pyelonephritis in immunocompetent host have been shown to be the dominant resident E.coli in __________
colon
76
which virulence factor is associated with the ability of E.coli to cause UTIs
the production of `pili`
it allows uropathogenic E.coli strains to adhere to epithelial cells and not be washed out with urine flow
77
aside from pili as the virulence factor of uropathogenic E.coli, what are the other virulence factos
flagella, cytolysins, aerobactin
78
this virulence factor facilitate bacterial dissemination
flagella
79
this virulence factor is also often characyerized as hemolysins, and can kill immune effector cells and inhibit phagocytosis and chemotaxis of certain white blood cells
cytolysins
80
this virulence factor allows the bacterial cell to chelate iron,; free iron is generally unavailable within the host for use by bacteria
aerobactin
81
what are the 5 gastrointestinal escherichia coli categories or serotypes
enterotoxigenic escherichia coli (ETEC)
enteropathogenic escherichia coli (EPEC)
enteroinvasive escherichia coli (EIEC)
enteroaggregative eschericcia coli (EAEC)
shiga toxin-producing escherichia coli (STEC)
82
diarrhegenic E.coli is also referred to as
enterovirulent E.coli
83
this diarrhegenic E.coli is associated with diarrhea in adults and specially in children living in tropical and subtropical climates, particularly in developing countries, where it is one of the major causes of infant bacterial diarrhea
ETEC - enterotoxigenic e.coli
84
the usually mild, self limiting disease caused by ETEC is characterized by
watery diarrhea
abdominal cramps
nausea
no vomiting or fever
85
is mucosal penetration and invasion a par5t of ETEC disease - enterotoxigenic E.coli, traveller's diarrhea
nope - poopsies lang yan, wala rin lagnat eh
86
this diarrhegenic E.coli is the first one to describe
enteropathogenic E.coli
87
the virulence of EPEC is defined as
producing attaching an deffacing lesions on the intestinal epithelium but inability to produce shiga toxins and LT or ST enterptoxins
88
this lacked the toxins of ETEC and the invasiveness of EIEC
EPEC
89
this diarrhegenic E.coli causes diarrheal oitbreaks in hospital nurseries and daycare centers, adult cases are rarely seen
pangbata lang
EPEC - infantile diarrhea nga diba
90
EPEC is characterized by
low grade dever
malaise
vomiting
persistent watery diarrhea
typically in younger children than 2 yrs of age
91
this diarrhegenic E.coli resemble shigella and produces dysentery with direct penetration, invasion, and destruction of the intestinal mucosa
enteroinvasive escherichia coli
92
enteroinvasive E.coli resemble shigella and produces dysentery with direct penetration, invasion, and destruction of the intestinal mucosa
which one is milder
EIEC
93
klebsiella most grow on what medium
simmons citrate and
potassium cyanide broth
94
do klebsiella produces H2s
NOPE
95
describe the methyl red and voges proskauer result of klebsiella
methyl red negative
voges proskauer positive
96
the abscence of _________ distinguishes Klebsiella from most other members of the family enterobacteriaceae
motility
97
klebsiella is non motile, with the exception of what specie
K.aerogenes
98
this specie of klebsiella is the most commonly isolated and has the distinct feature of possessing a large polysaccharide capsile
klebsiella pneumoniae
99
is the one responsible for the moist, mucoid colonies characteristic of K.pneumoniae
capsule
100
odor of proteus spp
burnt chocolate
101
the risk of infection from all vibrio can be reduced by the avoidance of __
raw or undercooked shellfish, particularly in warmer summer months
102
103
vibrio can grow flagella when grown in broth, however, there are 2 species that has the ability to swarm on 2 solid media, what are they
V.parahaemolyticus and V.alginolyticus
104
they have been described typically as curved or comma-shaped gram negative rods, but this morphology is often seen only in the initial gram stain of the clinical speccimen
vibrio spp
105
considered to be the worst outbreak in recent history
cholera
106
is an acute diarrheal disease that spreads mainly through contaminated water
cholera
107
the devastating clinical manifestation of cholera is the result of a powerful enterotoxin known as
cholera toxin or choleragen
108
