MIDTERM LEC: SPORE FORMING GRAM POSITIVE BACILLI Flashcards
1
Q
APPEARANCE: Gram positive (Purple)
A
SPORE FORMING GRAM POSITIVE BACILLI
2
Q
TECHNIQUE: Hucker’s modification
o Crystal violet
o Grams iodine
o Acid Alcohol
o Safranin
A
SPORE FORMING GRAM POSITIVE BACILLI
3
Q
Responsible for resistance to extreme conditions
A
SPORES (endospores)
4
Q
Protect from harsh environment
A
SPORES (endospores)
5
Q
process that bacteria forms
spores (protective appendages)
A
Sporalate
6
Q
Tend to make their own spores to protect themselves.
A
SPORES (endospores)
7
Q
THERMOPHILIC (can survive 55 degrees above).
A
SPORES (endospores)
8
Q
O2 requirement
BACILLUS:
A
Aerobic
9
Q
Catalase
BACILLUS:
A
POSITIVE
10
Q
Gas production
BACILLUS:
A
NEGATIVE
11
Q
O2 requirements
CLOSTRIDIUM:
A
ANAEROBIC
12
Q
Catalase
CLOSTRIDIUM:
A
NEGATIVE
13
Q
Gas production
CLOSTRIDIUM:
A
POSITIVE
14
Q
catalase reagent used:
A
3% hydrogen peroxide
15
Q
only observe in culture
media in tubes (plates seldom only)
A
Gas production
16
Q
Appearance (culture if there is
gas production):
A
bubbles, culture media can form cracks (tube)
17
Q
There are more than ____ species within the genus.
A
300
18
Q
Members of the genus Bacillus are metabolically diverse, and some species are ____ that grow best at _______.
A
thermophiles; 55° C or higher
19
Q
tend to live in a different temperature
A
Diverse
20
Q
The survival of Bacillus spp. in nature is aided by the formation of ______.
A
spores
21
Q
Largest pathogenic bacteria
A
Bacillus anthracis
22
Q
Large single organism
A
Bacillus anthracis
23
Q
Also known as “Anthrax Bacillus”
A
Bacillus anthracis
24
Q
Produces 2 virulence factors produced by _____ (can be found in the structure of Bacillus anthracis).
A
PLASMID
25
Bacillus anthracis VIRULENCE FACTORS:
1. D-glutamic acid capsule
2. Anthrax toxin
26
This particular isomer of glutamic acid is resistant to hydrolysis (addition of H2O) by host proteolytic enzymes because it is the
"unnatural" (zymogen) form of the amino
acid
D-glutamic acid capsule
27
process introduce water
bond
Resistance to hydrolysis
28
– produced D-glutamic acid
Although the capsule is necessary for
virulence, antibodies against the capsule do
not confer immunity
PLASMID PX02
29
produced by anthrax toxin
PLASMID PX01
30
PLASMID PX01 consist of three proteins:
1. Protective antigen (PA)
2. Edema factor (EF)
3. Lethal factor (LF)
31
Each of which individually is nontoxic but
which together act synergistically to produce
damaging effects.
PLASMID PX01 three proteins
32
serves as a necessary binding molecule for EF and LF, permitting their attachment to specific
receptors on the host cell’s surface
PROTECTIVE ANTIGEN (PA)
33
is an adenylate cyclase, release of water and electrolytes
EDEMA FACTOR (EF)
34
is a protease the inhibit protein synthesis
LETHAL FACTOR (LF)
35
PA + LF =
DEATH
36
PA + EF =
EDEMA
37
Bacillus anthracis
CLINICAL MANIFESTATIONS
1. Cutaneous Anthrax
2. Inhalation Anthrax
3. Gastrointestinal Anthrax
4. Injectional Anthrax
38
Direct contact; zoonotic contact
Starts when there is an open wound.
Cutaneous Anthrax
39
A small pimple (2 to 3 days after exposure)
eventually ulcerates and dries, forming a
depressed black necrotic central area known
as an** eschar or black eschar**
Cutaneous Anthrax
40
Cutaneous Anthrax Malignant postule;
90%
41
**Respiratory** anthrax
Also known as **Woolsorter’s disease**, is acquired when spores are inhaled into the
pulmonary parenchyma.
**Bioterrorism** agent
Inhalation Anthrax
42
**most fatal form** – paspas mukalat ; 2%
Ingestion of the spores
The symptoms include abdominal pain, nausea, anorexia, and vomiting. Bloody diarrhea can also occur.
Difficult to diagnose
Gastrointestinal Anthrax
43
Not common; mostly common in person
using drugs
Injection anthrax is characterized by soft
tissue infection associated with “**skin
popping”**
**Lack of eschar**, severity of disease, and increased mortality rate make this form
clinically distinct from the cutaneous form.
Injectional Anthrax
44
Bacillus anthracis TREATMENT
- The CDC recommends that ________be used for initial intravenous therapy until antimicrobial susceptibility results are known.
ciprofloxacin or doxycycline
44
Bacillus anthracis TREATMENT
- Most isolates of B. anthracis are susceptible to penicillin, but resistance can occur in the absence of ______.
B-lactamase production
45
Bacillus anthracis TREATMENT
- Standard form culture agar:
MHA (muellerhinton agar)
46
Bacillus anthracis TREATMENT
- what biosafety cabinet should used?
Biosafety Level 3
47
a large, square-ended, grampositive rod found singly or in chains.
B. anthracis LABORATORY DIAGNOSIS: MICROSCOPY
48
Gives the appearance of bamboo **pole arrangement.**
B. anthracis LABORATORY DIAGNOSIS: MICROSCOPY
49
Centrally located endospores
B. anthracis LABORATORY DIAGNOSIS: MICROSCOPY
50
B. anthracis LABORATORY DIAGNOSIS: STAIN
Schaeffer Fulton
51
The spores are generally not present in clinical samples.
B. anthracis LABORATORY DIAGNOSIS: MICROSCOPY
52
Spores can be observed with a spore stain.
With this technique, vegetative cells stain
red, and the **spores stain green.**
B. anthracis LABORATORY DIAGNOSIS: MICROSCOPY
53
SPORES STAIN GREEN
Malachite Green
54
VEGETATIVE CELLS STAIN RED
Safranin
55
Bacillus anthracis
LABORATORY DIAGNOSIS: CULTURE The term _______has been used to describe the colony morphology of B. anthracis on BAP
medusa/head/beaten egg whites
56
medusa/head/beaten egg whites Observe directly bacteria:
Inverted microscope
57
Culture medium of B. anthracis
String of pearls of MHA with penicillin
58
culture medium in terms of performing
antimicrobial susceptibility testing; standard culture medium
Mueller Hinton Agar (MHA)
59
Fried rice Bacillus
Bacillus cereus
60
is a relatively common cause of fried rice poisoning and opportunistic
Bacillus cereus
61
Food poisoning caused by B. cereus takes two forms:
diarrheal and emetic
62
causes food poisoning
Staphylococcus aureus
63
Meat and poultry
8-16 hours (long)
Heat labile enterotoxin – upon
introducing heat, the toxin will be dead.
Diarrheal Type
64
Fried rice
1-6 hours (short)
Heat stable enterotoxin
CLINICAL MANIFESTATIONS: vomiting
Emetic Type
65
____ from a food poisoning incident may be done to quantify and isolate B. cereus
Culture of suspected food
66
can also be use as a specimen
FRIED RICE
67
________ food poisoning by this organism is confirmed.
>105 B. cereus/gram
68
Most food poisoning cases caused by B. cereus do not require ______ treatment.
antimicrobial
68
To confirm the organism as the cause of the
disease, viable counts from the stool should
also be ________.
at least 105 cells per gram
69
In contrast to B. anthracis, B. cereus is
resistant to penicillin and all of the other Blactam antibiotic for the _______
carbapenems
70
B. cereus Treatment with vancomycin or clindamycin with our without an aminoglycoside has been successful.
TRUE
71
Bacillus cereus bacteria stained with _____ to display their flagella.
Leifson dye
72
B. cereus Arrangement of flagella:
Peritrichous
73
CATALASE +
B. anthracis, B. cereus
74
Lecithinase +
B. anthracis, B. cereus
75
NON-MOTILE
B. anthracis
76
MOTILE
B. cereus
77
# BAP Hemolysis
Gamma hemolysis
B. anthracis
78
# BAP Hemolysis
Beta hemolysis
B. cereus
79
differentiate B. antracis and B. cereus
Motility and Hemolysis
80
ANAEROBIC SPORE FORMING GRAM (+) BACILLI:
* Clostridium tetani
* Clostridium perfringens
* Clostridium botulinum
* Clostridium difficile
81
Clostridium causing Tetanus (Spasmic Paralysis)
Clostridium tetani
82
Also known as Racquet Bacillus
Clostridium tetani
83
Endospore are round and terminal
(drumstick//tennis racquet appearance) –
due to locations of endospres
Clostridium tetani
84
Spores are highly resistant to adverse conditions
Clostridium tetani
84
Motile by peritrichous flagella
Clostridium tetani
85
Iodine (1%) in water is able to kill the spore within a few hours
Clostridium tetani
86
Neurotoxin and an essential pathogenic product
Tetanospasmin
87
Clostridium tetani VIRULENCE FACTORS:
Tetanospasmin
88
Toxic to humans and various animals when
injected parenterally, but it is not toxic by the
oral route
Tetanospasmin
89
Causes increasing excitability of spinal cord neurons and muscle spasm.
Tetanospasmin
90
This neonate is displaying a bodily rigidity
orduced by C. tetani exotoxin, called
neonatal tetanus
91
Sir Charles Bell's portrait of a soldier dying of
tetanus. The characteristic rigidity of the
body is referred to as .
opisthotonos and risus sardonicus
92
Clostridium tetani
LABORATORY DIAGNOSIS
Specimen:
Wound exudates using capillary tube
o Red ring (anticoagulant; HEPARIN)
93
is a good method for identifying
Clostridium.
Gram stain
94
Cl. tetani is a Gram positive rod, motile with a round terminal spore giving a ____ appearance.
drumstick
95
Clostridium tetani
LABORATORY DIAGNOSIS
Culture:
o On blood agar and incubated anaerobically
o Growth appears as a fine spreading film
96
Causative agent of gas gangrene
Clostridium perfringens
97
Also known as GAS GANGRENE
BACILLUS
Clostridium perfringens
98
Can also cause food poisoning
Clostridium perfringens
99
Non-motile, capsulated with Subterminal spores
Clostridium perfringens
100
centrally located sprores
Bacillus anthracis
101
terminal spores
Clostridium tetani
102
subterminal spores
Clostridium perfringens
103
Clostridium perfringens VIRULENCE FACTORS: TOXINS
* a toxin (phospholipase C, lecithinase)
* B toxin
* Enterotoxin
104
Clostridium perfringens MOST IMPORTANT TOXIN
a toxin (phospholipase C, lecithinase)
105
Lyses RBCs, platelets, leukocytes
and endothelial cells
a toxin (phospholipase C, lecithinase)
106
Increased vascular permeability with massive hemolysis and bleeding tissue destruction.
a toxin (phospholipase C, lecithinase)
107
Responsible for necrotic lesions in
necrotizing enterocolitis
B toxin
107
Hepatic toxicity and myocardial
dysfunction
a toxin (phospholipase C, lecithinase)
108
Clostridium perfringens
LABORATORY DIAGNOSIS
Specimen:
Histological specimen (tissues)
or wound exudates
108
o heat labile (can be destroyed by heat) toxin produced in colon
o for food poisoning
Enterotoxin
109
# ```
Clostridium perfringens
Histological specimen transferred aseptically
into a _________ & used immediately for microscopic examination & culture
sterile screw-capped bottle
110
Clostridium perfringens
Specimens of exudates should be taken
from the deeper areas of the wound where
the infection seems to be most pronounced.
TRUE
111
Clostridium perfringens
LABORATORY DIAGNOSIS
CULTURE:
Anaerobically at 37 C
111
Exhibit Double zone of hemolysis (two zone beta hemolysis)
Clostridium perfringens LABORATORY DIAGNOSIS
112
Clostridium perfringens
blackening of meat will observed with the
production of H2S and NH3
Robertson’s cooked meat medium
113
It ferments many carbohydrates with acid & gas
Clostridium perfringens LABORATORY DIAGNOSIS
114
Nagler reaction (+)
Clostridium perfringens LABORATORY DIAGNOSIS
115
It acidified litmus milk with stormy clot production
Clostridium perfringens LABORATORY DIAGNOSIS
116
This test is done to detect the
LECITHINASE ACTIVITY
NAGLER REACTION
116
Clostridium perfringens
LABORATORY DIAGNOSIS:
* NAGLER REACTION
* LITMUS MILK
* Reverse CAMP Test
117
alpha-toxin
NAGLER REACTION
118
Inoculated on the medium containing human
serum or egg yolk (contains lecithin)
NAGLER REACTION
119
NAGLER REACTION The plate is incubated anaerobically at
37° C for 24 hrs
120
Colonies of Cl. perfringens are surrounded
by zones of turbidity due to lecithinase
activity and the effect is specifically inhibited
if Cl. perfringens antiserum containing alpha
antitoxin is present on the medium.
NAGLER REACTION
121
LITMUS MILK ACIDIC REACTION =
Pink Color
122
LITMUS MILK BASIC REACTION =
Blue Color
123
POSITIVE LITMUS MILK:
acid with stormy clot fermentation
124
CAMP Positive S. agalactiae (Group B
Streptococcus) is streaked in SBA and C.
perfringens is streaked perpendicular to it.
Reverse CAMP Test
125
(+) “arrowhead” (enhanced) hemolysis is seen in between = C. perfringens
Reverse CAMP Test
126
CAUSES BOTULISM (Flaccid Paralysis)
Clostridium botulinum
127
Seven neurotoxic subtypes, labeled A-G
Clostridium botulinum
128
First recognized and isolated in 1896 by Van Ermenhem
Clostridium botulinum
129
Botulism is a neuroparalytic disease
Clostridium botulinum
130
Once released into the bloodstream it
irreversibly binds to the acetylcholine
receptors in the neuromuscular junction
Clostridium botulinum
131
It alters the mechanism for acetylcholine
release, making the neuron unresponsive to
action potentials
Clostridium botulinum
132
Most common form
Afflicts babies from 1 week – to 1 year
Antigenic variation types A/B
Floppy Baby Syndrome
133
Infant Botulism:
Floppy Baby Syndrome
134
Floppy Baby Syndrome Caused by:
Ingesting contaminated foodstuff
Untreated natural honey and corn syrup
Household dust containing C. botulinum
spores
135
Clostridium botulinum MANAGEMENT:
must be administered intravenously (recovery takes several weeks)
Trivalent (A,B,E) antitoxin
136
Clostridium botulinum MANAGEMENT:
is administered if necessary.
Mechanical respirator
137
Clostridium botulinum
LABORATORY DIAGNOSIS:
Toxins found in serum, leftover food
In infants, found in stool
Mice injected with toxin die rapidly
Spores are oval, subterminal
Lipase positive
138
A common cause of nosocomial antibioticassociated diarrhea (AAD) & antibiotic (Clindamycin) -associated
pseudomembranous colitis
Clostridium difficile
139
The only nosocomial organism that is
anaerobic and forms spores (survive >5
months and hard to destroy)
Clostridium difficile
140
Clostridium difficile
Pathogenesis is mainly due to toxin production:
Infective dose is <10 spores
141
Cyclocidin-Cefoxitin Fructose
Agar POSITIVE
(+) colonies with Yellow Halo
141
Clostridium difficile
LABORATORY DIAGNOSIS
Specimen:
Stool
142
Clostridium difficile
LABORATORY DIAGNOSIS
Cultured on:
Cyclocidin-Cefoxitin Fructose
Agar
143
a selective culture media
Cyclocidin-Cefoxitin Fructose
Agar
144
sweet or fruity odor
Pseudomanas aeruginosa
144
Horse manure odor
Clostridium difficile
145
Old sock
Staphylococcus aereus
145
Freshly lawn grass odor
Nocardia spp.
146
C. difficile toxin testing: ______if not used/tested for longer than 48 hours. No preservatives added because it will inhibit the toxins.
Should be freezed (78C)
147
Best strategy for C. difficile testing
For clinical use:
two-step testing uses initially EIA detection screening followed by cytotoxicity assay or toxigenic culture for confirmation
148
C. difficile testing Gold standard:
stool culture followed by
toxigenic culture assay
149
NON-MOTILE
C. perfringens
150
MOTILE
* C. botulinum
* C. tetani
* C. difficile
151
POSITIVE LECITHINASE
C. perfringens
152
NEGATIVE LECITHINASE
* C. botulinum
* C. tetani
* C. difficile
153
NEGATIVE LIPASE
C. perfringens
154
POSITIVE LIPASE
C. botulinum
155
NEGATIVE LIPASE
C. tetani
C. difficile
156
POSITIVE LACTOSE
C. perfringens
157
NEGATIVE LACTOSE
* C. botulinum
* C. tetani
* C. difficile
158
POSITIVE GLUCOSE
C. perfringens
159
POSITIVE GLUCOSE
* C. botulinum
* C. difficile
160
NEGATIVE GLUCOSE
C. tetani
