micro details Flashcards
1
Q
what virulence factor allows E coli to cause neonatal meningitis?
A
K-capsule (usually K-1)– inhibs complement, phagocytosis and other host response. (the capsule = immunogenic and Abs = protective)
2
Q
why are B-cells not very effective agst TB?
A
facultative IC org–mainly reside w/in Macrophages
3
Q
major toxin of C. Diptheria works by…
A
inactivates EF-2 via ribosylation, thus inhibiting host-cell prot synth
4
Q
major tox in of C. Diptheria = closest to what other toxin?
A
Pseudomonas aeruginosa exotoxin A- inactivates EF-2 via ribosylation, thus inhib host-cell prot synth
5
Q
How does the Pertussis toxin work?
A
Disinhibits adenylate cyclase via Gi ADP ribosylation, increasing cAMP production in host cell; causes increased histamine sensitivity and phagocyte dysfunc
6
Q
How does Cholera toxin work?
A
Activates adenylate cyclase via Gs ADP ribosylation, increasing cAMP production in the host cell; causes secretory diarrhea, dehydration & electrolyte deposition
7
Q
which toxin increases cAMP by Gi ADP ribosylation?
A
Pertussis
8
Q
which toxin increases cAMP by Gs ADP ribosylation?
A
Cholera
9
Q
which toxins are AB toxins where the B subunit induces receptor mediated endocytosis/internalization of a toxin by enterocytes and the A subunit catalyses the removal of an Adenosine residue, which prevents binding of tRNA to the 60S ribosomal subunit/inhib prot synth?
A
Shigella toxin and shiga-like-toxin (E. Coli)
10
Q
Name 6 common illnesses caused by lysogenic phages
A
- HUS (shiga-like-toxin)
- TTP (shiga-like toxin)
- Botulism
- cholera
- diptheria
- Toxic shock-like sysdrome (S. pyogenes)
11
Q
which bact. = assoc. w/fever, abdo pain, diarrhea and faintly erythematous macules on abdo called “rose spots”
A
salmonella typhi - typhoid fever
12
Q
What are the virulence factors acquired by specialized transduction?
A
REMEMBER– “specialized transduction = lysogenic phage!”
- COBEDS
1) Cholera
2) O-toxin from salmonella
3) Botulism
4) Exotoxins (STLS from Strep pyog)
5) Diptheria
6) Shiga-like-toxin (causes HUS and TTP)
13
Q
Name 6 common illnesses caused by lysogenic phages
A
- HUS (shiga-like-toxin)
- TTP (shiga-like toxin)
- Botulism
- cholera
- diptheria
- Toxic shock-like sysdrome (S. pyogenes)
14
Q
what is specialized transduction?
A
DNA being introduced from lysogenic phages (they integrate into DNA, and when they leave, they accidentally take some of the original bacteria with them. When they move on to the next bacteria, they infect that bacteria with the old host bacteria).
15
Q
What are the virulence factors acquired by specialized transduction?
A
REMEMBER– “specialized transduction = lysogenic phage!”
- COBEDS
1) Cholera
2) O-toxin from salmonella
3) Botulism
4) Exotoxins (STLS from Strep pyog)
5) Diptheria
6) Shiga-like-toxin (causes HUS and TTP)
16
Q
LPS is also called…
A
endotoxin
17
Q
what is the toxic part of LPS?
A
lipid A
18
Q
name 3 bacterial toxins that interfere w/ protein synthesis:
A
- Diptheria Corneybacterium
- Pseudomonas exotox
- Shigella (shigella-like)
19
Q
many exotoxins are AB toxins where the A portion ______ and the B portion _____
A
A: active portion of toxin
B: Binds to cell receptor
20
Q
name 4 bacterial toxins that result in increased cAMP (associated w/fluid moving into another space)
A
I like cAMPing BC it’s ChEAP
- B. Cerius (heat labile enterotox- activate adenylate cyclase)
- C. Jejuni (enterotox- activate adenylate cyclase)
- CHolera (cholera tox- ADP ribosylation activates Gs- activates adenylate cyclase)
- . ETEC (heat labile toxin, activates Gs)
- Anthrax (edema factor- intrinsic adenylate cyclase activity in toxin)
- Pertussis (ADP ribos. INACTIVATES Gi)
21
Q
name 3 bacterial toxins that interfere w/ protein synthesis:
A
- Diptheria
- Shigella (shigella-like)
- Pseudomonas exotox
22
Q
Haemophilus grows on…
A
chocolate Agar- w/factors 5 and 10
23
Q
what grows on Thayer Martin media?
A
Gonorrhea– you have too many martinis, you can get gonorrhea
24
Q
pertussis grows on…
A
Bordet-genou (a potato medium!)
BORDETella Pertussis
25
Diptheria grows on
Tellurite
26
What grows on MacConkey agars?
lactose-fermenting GN
| contains bile salts that prevent GP from growing
27
What grows on Charcoal yeast extract w/cysteine?
Legionella
28
Legionella grows on...
Charcoal yeast extract w/cysteine
29
Fungi grows on...
Sabaraud agar
30
4 antibact that inhib cell wall...
1. Penicillins
2 Cephalosporins
3. Vancomycin
4. Carbapenims
31
which has an outer membrane, GN or GP?
GN
32
which has LPS, GN or GP?
GN
33
which has thick peptidoglycan layer, GP or GN?
GP
34
which stains pink, GP or GN? and which stains purple?
```
pink = GN
purple = GP
```
35
which has cytoplasmic membrane, GP or GN?
both!
36
which has teichoic acid, , GP or GN?
GP-- used for attachment
37
which stains pink, GP or GN? and which stains purple?
```
pink = GN
purple = GP
```
38
which genetic mechanism(s) (Hfr, Transduction, Conjugation, Transformation) requires a phage?
transduction
39
which genetic mechanism(s) requires homologous recombination?
Hfr
Transduction
Transformation
(all forms where new DNA = being incorp into chromosomal DNA)
40
which genetic mechanism(s) (Hfr, Transduction, Conjugation, Transformation) requires naked DNA
transformation
41
which bacteria are transformation competent?
SHiN bacteria
S. pneumo
HiB
Neisseria
42
which genetic mechanism(s) (Hfr, Transduction, Conjugation, Transformation) requires oriT + tra for transfer of genetic material?
conjugation (plasmid w/transposon on board)
43
which genetic mechanism(s) (Hfr, Transduction, Conjugation, Transformation) requires oriT for transfer of genetic material?
Hfr and conjugation
44
what is oriT?
Origin of Transfer:
short DNA seq. necessary for transfer of a bacterial plasmid/chromosomal DNA from a bacterial host to recipient during bacterial conjugation. (The oriT is cis-acting - it is found on the same plasmid that is being transferred, and is transferred along with the plasmid. The origin of transfer consists of three functionally defined domains: a nicking domain, a transfer domain, and a termination domain.)
45
which genetic mechanism(s) (Hfr, Transduction, Conjugation, Transformation) requires oriT + tra for transfer of genetic material?
conjugation (plasmid w/transposon on board)
46
majority of multi-drug resistant orgs arise from what genetic mech?
conjugation
47
3 bact causes of typical pneumonias (gen represented as older, really sick people w/lobar pneumonia)
1. strep pneumo
2. HiB
3. S. aureus
48
txt diptheria w/
penicillin (or erythromycin if penicillin allergy) + antitoxin
49
two unique things about mycoplasma pneumoniae and Ureaplasma
1. no cell wall!
| 2. uses sterols in cell membrane
50
super sick kid, not vaccinated (immigrant/vac. status unknown), bull neck (LAD), psudomembrane
Diptheria!
| corney bacterium diptheria
51
txt diptheria w/
penicillin, antitoxin + vaccine
52
how do you txt strep throat from S. pyogenes?
penicillin
53
how does sinusitis present?
after viral ifxn, sinus pain, head congestion, frontal tenderness/maxillary tenderness
54
otitis externa- ear pain = assoc. w/what 2 bugs?
1. Pseudomonas aeruginosa-- from SWIMMING IN INFECTED WATER
2. S. aureus
P.S. my ear hurts!!!
55
how can you tell if sinusitis = caused by anaerobe?
smelly bc they make H2S
56
how does sinusitis present?
after viral ifxn, sinus pain, head congestion, frontal tenderness/maxillary tenderness
57
otitis externa- ear pain = assoc. w/what 2 bugs?
Pseudomonas aeruginosa-- from SWIMMING IN INFECTED WATER
S. aureus
P.S. my ear hurts!!!
58
Pseudomonas causes what two things from being in water too long?
Otitis externa
| Hot tub folliculitis
59
diarhea from shigella is ALWAYS...
BLOODY!! (bacillary dysentery)
| - SHit i'm BLEEDING from SHigella
60
what is the most common bacterial diarrhea, and it comes from spoiled chicken?
C. jejuni
61
salmonella is associated w/which foods?
chicken and egg products
62
diarhea from shigella is ALWAYS...
BLOODY!! (bacillary dysentery)
| - SHit i'm BLEEDING from SHigella
63
B. cereus = assoc w/
reheating rice (chinese food, etc)
64
C. perfringens = assoc w/what food
reheated meat
65
vibrio cholerae = assoc. w/what food?
seafood
66
what is assoc w/ honey in babies?
C. botulinum ---> neurotoxin, can't release ACh
67
ifxn w/EHEC commonly causes what 2 extraGI things?
HUS
TTP
(O157:H7 Shiga-like toxin)
68
0157:H7
EHEC- shiga-like toxin
69
undercooked hamburgers = commonly assoc w/
EHEC
70
ifxn w/EHEC commonly causes what 2 extraGI things?
HUS
TTP
(O157:H7 Shiga-like toxin)
71
what bact = assoc w/UTI and grows red, maraschino-cherry like colonies?
serratia marascens
72
most common cause of UTI
E coli
73
which common cause of UTI = assoc. w/swarming on agar and struvite stones?
Proteus
74
most common cause of osteomyelitis in people w/out sickle cell?
people w/sickle cell?
w/out: s. aureus
| with: salmonella
75
itchy, strawberry cervix and parasites that swim on wet mount =
trichomonas vaginitis
| the itchy TRICky VAGINITIS
76
painful chancroid...
haemoph. ducrei
77
possitive wiff test (KOH smells like fish) assoc w/
bacterial vaginosis
bact. vaginOsis smells w/kOh
78
itchy, strawberry cervix and parasites that swim on wet mount =
trichomonas vaginitis
| the itchy TRICky VAGINITIS
79
painful chancroid...
haemoph. ducrei
80
most common cause of meningitis in newborn
GBS >>E. Coli >> Listeria (crosses placenta)
81
most common cause of men. > 40yo
S. pneumo > N. Men > > > listeria
82
most common cause of meningitis in 3mo - 5 years in vacc. kid
S. pneumo
83
why can't you txt mycoplasma pneumoniae w/beta-lactams?
bc no cell wall!!!
84
if someone has a penicillin allergy, what do you txt diptheria w?
antitoxin + erythromycin
85
if something grows on sabaroud agar, you know that it's what?
a fungi! (ie eliminate anything that's not a fungi from your answer choices)
86
S. pneumo and Haemophilus = most common causes of what two things, regardless of vaccination status
1. sinusitis
2. otitis media
** bc S.Pneumo has sooo many serotypes, and it's generally NOT the HiB serotype that causes sinusitis or otitis media, so vac doesn't protect agst them.
87
if someone has a penicillin allergy, what do you txt diptheria w?
antitoxin + erythromycin
88
pseudomonas aeruginosa ---> otitis externa in what two scenarios?
1. swimmer's ear
| 2. diabetic
89
S. pneumo and Haemophilus = most common causes of what two things, regardless of vaccination status
1. sinusitis
2. otitis media
** bc S.Pneumo has sooo many serotypes, and it's generally NOT the HiB serotype that causes sinusitis or otitis media, so vac doesn't protect agst them.
90
thin, watery, malodorous discharge from the vagina =
bacterial vaginosis
91
frothy, green discharge from the vagina
trichomonas vaginalis
92
meningitis vaccine = what kind?
conjugate-- capsule + protein ---> allows T-cell/memory response
93
is campylobacter jejuni invasive or toxin mediated?
invasive
94
is salmonella invasive?
yes
95
is Shigella invasive, toxin mediated, or both?
both-- it invades and then secretes exotox that inhibs prot. synth!
96
is EHEC invasive?
no, toxin mediated
97
is C. Botulinum invasive?
no, toxin mediated
98
"ground glass" appearance of HEPATOCYTES (finely granular, eosinophilic) = assoc w/what virus?
HBV-- fine cytoplasmic granules of HbSAg
99
is EHEC invasive?
no, toxin mediated
100
chronic HBV causes what morphologic changes to hepatocytes?
ballooning degen, hepatocyte necrosis, portal inflammation, and the cytoplasm = filled w/sheres/tubules of HbsAg-- finely granular, eosinophilic "ground glass"
101
"ground glass" appearance of HEPATOCYTES (finely granular, eosinophilic) = assoc w/what virus?
HBV-- fine cytoplasmic granules of HbSAg
102
lymphoid aggregates w/in the portal tracts + focal areas of macrovescicular steatosis in Hepatocytes?
HCV
103
mushrooms (like Amanita phalloides, known as the death cap) are taken to the liver where they have what toxic effect?
inhib mRNA synth
| Mushrooms inhib Mrna synth, by binding RNA polym II
104
4 species of GP rods
1. corneybacterium
2. listeria
3. Bacillus (like B. Cerius)
4. Clostridium
105
hemolytic pattern on blood agar:
| Staph aureus?
beta
106
hemolytic pattern on blood agar: S. epidermidis
gamma
107
hemolytic pattern on blood agar: S. saprophyticus
gamma
108
hemolytic pattern on blood agar: Strep Pyogenes (GAS)
beta
109
hemolytic pattern on blood agar: GBS
beta
110
hemolytic pattern on blood agar: Strep Pneumo
alpha
111
hemolytic pattern on blood agar: Strep mutans
alpha
112
hemolytic pattern on blood agar: Strep Bovis
gamma
113
Protein A is made by _____ and does what?
S. Aureus- binds Fc portion of IgG ---> inhibs opsonization/phag
114
bugs most likely to cause endocarditis on elderly person w/artificial heart valve?
S. epidermitis-- makes biofilm that sticks to valve
| Strep viridans-- makes dextrans that bind to fibrin
115
Do GP or GN form spores?
ONLY GP!!
116
only GP that has LPS?
Listeria
117
What distinguishes btwn catales neg, GP cocci in chains that are alpha hemolytic?
optochin
sensitive: S. pneumo
resistant: S. viridans (sanguis and mutans)
118
what distinguishes btwn catalase neg, GP cocci in chains that are Beta-hemolytic?
bacitracin:
Resistant: GBS
sensitive: GAS
119
what distinguishes btwn catalase neg, gamma hemolytic GPCs?
growth in NaCl
E. faecalis: can grow
S. bovis: doesn't grow
120
if something is cagulase + what does that mean?
can coagulate-- ie make an abcess, wall itself off w/fibrin (S. aureus)
121
is S. pyogenes quellun +
yes-- has a capsule, and it swells in vitro
122
S. mutans = assoc w/
dental carries-- bacteremia after a dental procedure ---> subacute endocarditis bc S. mutans makes dextrose/binds fibrin
123
what is number 1 cause of pneumonia in adults > 60, #1 cause of meningitis in adults and #1 cause of otitis media in kids?
S. pneumo
124
txt for S. pneumo?
macrolides, ceftriaxone, amoxicillin
125
child vaccine for S. pneumo is a...
conjugate vaccine- 7 serotypes + prot
126
adult vaccine for S. pneumo has
23 serotypes
127
the capsule of S. pyogenes is made of...
hyaluronic acid
128
Major virulence factore for GAS
M prot- cleaves C3 convertase which inhibs complement cascade/opsonization
129
Txt for vanc. resistant enterococci (VRE)
linezolid, streptogrammins
130
twt listeria w
ampicillin and gentamycin for IC
131
xt C. diptheria w/
antitoxin + ERYTHROMYCIN
132
gray membrane, myocarditis and recurrent laryngeal nerve palsy = consistent w/
diptheria
133
vaccine for diptheria =
toxoid
134
what are the aerobic, spore forming GP rods?
B. cereus and B. Anthracis
135
which is the motile aerobic, spore forming, GP rod- B. cereus or B. Anthracis?
B. cereus
136
two toxins in B, cerus?
heat stable exotoxin: vomiting/increase cAMP
| heat labile: diarrhea
137
3 toxins in B anthracis
1. protective Ag
2. Lethal factor
3. Edema factor (an adenylate cyclase)
138
what is cause of painless skin ulcer, a black eschar w/ significant local edema
B. Anthracis
139
txt for anthrax
1. cipro
| 2. doxycycline
140
3 motile, spore-forming, anaerobic GPR
C. tetani
C. botulinim
C. diff
141
non-motile, spore-forming anaerobic GPR?
C. perfringens
142
txt for C. tetani
toxoid vaccine, hyperimmune globulin, penicillin plus spasmoytic
143
txt for infant botulism
human IvIG
144
txt for adult botulism?
antitoxin + penicillin
145
txt for C. diff?
change/stop abx
146
txt for C perfringrens
Penicillin G +/- clindamycin, plus debridement
147
what grows on egg yolk agar?
C. perfringens
148
txt C. diff w?
metronidazole/oral vanco
149
metronidazole = used to txt...
1. things w/flagella
| 2. anearobes below diaphragm
150
2 non-spore forming GPR
1. nocardia (soil)
| 2. actinomyces (mouth)
151
only bacterium w/a polypeptide capsule?
B. Anthracis
152
what two toxins increase cAMP by ribosylating Gs, leading to increased adenylate cyclase activity? Which increases cAMP by inhibiting Gi?
Cholera and ETEC heat labile toxin ---> Gs
| Pertussis inhibs Gi
153
The EHEC/verotoxin works by...
inhibiting the 60s ribosomal subunit
154
2 types of cutaenous mycoses
```
dermatophytosis (ring worm- MET)
pitryiasis versicolor (turns skin white Malassezia furfur)
```
155
3 types of dermatophytes (aka ringworm)
i MET keith and he gave me a RING
Microsporum
Epidermophyton
Trichophyton
156
txt for Enterobius Vermicularis (aka pinworm)?
mBENDazole-- like you have to BEND over to scratch your ass
157
mycoses w/systemic involvement (most often affecting lungs)
histoplasmosis, coccidiodoses, blastomycoses, paracoccidioses
158
opportunistic mycoses
candida, aspergillus, mucor/rhizopus
159
aspergillus- acute or wide angle? septate or aseptate?
Acute (less than 45) w/septae
160
mucor- acute or wide angle? septae or asept?
wide angle (90) and aseptae
161
malassezia furfur gives you what presentation?
cutaneous mycoses that turns your skin white (petryasis versicolor/aka tinea versicolor)
162
"spaghetti and meatballs" morphology on KOH prep refers to...
malassezia furfur-- gives you tinea versicolor- a cutaneous ifxn which turns your skin white
163
How does malassezia furfur turn your skin white?
produces acids that damage melanocytes and cause hypopigmented patches
164
txt malassezia furfur (cutaneous mycose: tinea versicolor- turns skin white bc damage to melanocytes)
miconazole, selenium sulfide (selsun)
165
in p. vivax/p.ovale what is the form that infects RBCs?
MAROzoites
--"marrow"zoites infect RBCs which come from marrow
166
what is unique about P. vivax/P.ovale?
latent form-- Hypnazoites that infect Hepatocytes
167
chloroquine txts what part of P. vivax/P.ovale ifxn. What does it not txt?
txts marozoites in Q
| DOES NOT TXT latent Hypnazoites in Hepatocytes-- need primaquine for that
168
why is primaquine added to chloroquine txt of P. vivax/P.ovale?
to kill latent hypnazoites in hepatocytes
169
neutropenic pts (esp assoc w/leukemia/lymphoma) are at risk for which mycoses?
aspergillus fumigatus
170
ABCDEFGs of corneybacterium diptheriae
```
Adp-ribosylates
Bacterial phage
Corneybacterium
Diptheriae
Elongation-
Factor 2
Granules (metochromatic blue and red w/aniline dyes)
```
171
major risk w/corneybacterium diptheriae?
myocarditis- cardiomyopathy = most common COD
172
what ferments lactose on MacConkee?
macConKEE'S
1. Citrobacter
2. Kliebsiella
3. E. coli
4. Enterobacter
5. Serratia
173
EMB agar?
lactose fermenting-- grows purple/black. E.coli grows purple/green
174
what inhibits entry of Vanco and Penn G in GN?
outer membrane layer
175
GN bacilli = resistant to Pen G. but may be susceptible to...
Penicillin derivs ampicillin and amoxicillin
176
does Neisseria Gon. have a polysach capsule? What about N. Meningitidis?
N. GoNO: NO
| N. Menin: yes
177
Fits-Hug- Curtis...
RUQ pain from liver capsule inf due to N. Gon.
