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USMLE Step 1 Random Facts > Micro > Flashcards

Micro Flashcards

1
Q

characteristic tumbling motility

A

Listeria monocytogenes

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2
Q

transmitted via respiratory droplets

A

N.meningitidis, RSV, H.influenzae, M.tuberculosis

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3
Q

arthropod bites

A

leishmaniasis (sandfly)
malaria (Anopheles mosquito)
Chagas (reduviid bug)
Lyme dz (Ixodes tick bite)

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4
Q

needle stick transmission

A

HBV, HCV, HIV

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5
Q

H.influenzae

A

small, gram neg coccobacilliary rod
epiglottis, meningitis, otitis media, pneumonia
“haEMOPhilus”

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6
Q

causes a palm & sole rash?

A

2ndary syphilis
Rocky mountain spotted fever
coxsackievirus A
Kawasaki dz

“you drive KAWASAKI CARS w/ your HANDS AND FEET”
(CA = cox A, R = RMSF, S = syphilis)

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7
Q

can cross placenta and allow infection from mother to fetus?

A 
TORCHES:
TOxoplasma gondii
Rubella
Cytomegalovirus
HErpes, HIV (HSV-2 transmitted VIA DELIVERY)
Syphilis
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8
Q

2 obligate intracellular parasites (require host ATP for energy)

A

Chlamydia

Ricketssiae

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9
Q

common causes of atypical pneumonia (class types)

A

Mycoplasma
Legionella
Chlamydia
Viruses

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10
Q

5 pediatric diseases w/ rash

A 
Measles
Rubella
Scarlet fever (S.pyogenes)
Roseola (HHV-6)
Erythema infectiosum (parvovirus B19) - "slapped cheeks"
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11
Q

5 causes of common cold

A 
rhinovirus
coronavirus
adenovirus
influenze C virus
coxsackievirus
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12
Q

3 common causes of conjunctivitis

A

H.influenzae
Adenovirus
S.pneumoniae

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13
Q

most common viral cause of mental retardation in US

A

CMV

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14
Q

cancers caused by EBV

A 
Burkitt's lymphoma
nasopharyngeal carcinoma (in East Asians)
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15
Q

HBV, HCV, HDV 4 characteristics:

A

Blood transmission
Chronic carrier state
Cirrhosis
HCC

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16
Q

smallpox eradicated bc of?

A

1) only ONE serotype existed
2) NO CARRIER state
3) NO ANIMAL RESERVOIRS

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17
Q

enveloped viruses?

A

susceptible to anything capable of destroying lipids (ex. bile acids)

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18
Q

use host cell TRANSLATION machinery

A

ssDNA viruses

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19
Q

use host cell TRANSCRIPTION machinery

A

dsDNA viruses

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20
Q

Parvovirus B19 =

A

ssDNA linear, nonenveloped

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21
Q

HPV =

A

nonenveloped, dsDNA circular

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22
Q

HPV uses what 2 factors to grow?

A

E6 (blocks p53), E7 (blocks Rb)

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23
Q

JC virus =

A

dsDNA circular, nonenveloped

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24
Q

adenoviruses =

A

dsDNA linear, nonenveloped

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25
Q

adenoviruses can cause?

A

resp tract infection
conjunctivitis
hemorrhagic cystitis
gastroenteritis

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26
Q

adenoviruses remain latent where?

A

tonsillar adenoids following infection

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27
Q

adenoviruses contain what factor?

A

hemagglutinin fibers in each of 12 vertices of capsid

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28
Q

HSV-1, HSV-2, VZV =

A

enveloped, dsDNA linear

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29
Q

HSV, CMV, EBV envelope?

A

only virus that obtains envelope by budding from nuclear membrane

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30
Q

HSV-1 can cause?

A

gingivostomatitis
keratoconjunctivitis (recurrence of –> common cause of blindness in U.S)
cold sores
**temporal lobe encephalitis (focal necrosis)

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31
Q

HSV-1 dormant in?

A

trigeminal ganglion

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32
Q

HSV-2 dormant in?

A

lumbosacral ganglion

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33
Q

HSV-2 passed from mother to fetus can cause?

A

congenital defects
abortion
neonatal encephalitis

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34
Q

most common cause of encephalitis in U.S

A 
HSV-1 = adults
HSV-2 = neonates
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35
Q

“dew on a rose petal”

A

VZV

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36
Q

VZV dormant in?

A

DRG

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37
Q

CMV =

A

dsDNA linear, enveloped

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38
Q

CMV causes?

A 
cytomegalic inclusion dz [deafness, hepatosplenomegaly, microcephaly in newborns)
heterophil-NEGATIVE mononucleosis
retinitis (esp in AIDS pt)
pneumonia (esp in transplant pts)
esophagitis
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39
Q

cancers ass w/ EBV?

A

Burkitt’s lymphoma, nasopharyngeal carcinoma (East Asians)

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40
Q

EBV dormant in?

A

B cells

bind and infect B cells via C3d complement receptor

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41
Q

atypical lymphocytes charact of?

A

EBV infection

cytotoxic T-lymphocytes react against infected B cells

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42
Q

HBV =

A

enveloped, dsDNA circular

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43
Q

HBV and weak immune response =

A

chronic state

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44
Q

HBV tx?

A

alpha-IFN or pegylated alpha-IFN

lamivudine

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45
Q

smallpox =

A

enveloped, dsDNA linear

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46
Q

smallpox presentation?

A

start as macules –> evolve to pus-filled vesicles –> crust over in 2-3 wks –> infectious particles released

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47
Q

molluscum contagiosum =

A

enveloped, dsDNA linear

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48
Q

unlike HSV or VZV, molluscum contagiosum is?

A

limited to epidermis

NO latent state

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49
Q

Molluscum contagiosum presentation?

A

flesh-colored pearly nodules/papules w/ central crater

“dome-like”

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50
Q

features of acid-fast bacilli?

A

cell wall w/ mycolic acid (a lipid) –> makes wall hydroPHOBIC
after stained, retains stain!

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51
Q

spirochetes shape/motility?

A 
corkscrew bc flexible/thin cell walls
periplasmic flagella (b/w outer membrane and cell wall) --> corkscrew motility
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52
Q

mycoplasma distinguishing feature?

A

no cell wall

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53
Q

chlamydia/rickettsiae species are?

A

obligate intracellular bacteria

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54
Q

mycolic acid cell wall protects from?

A

phagocytosis, germicides, dryness

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55
Q

M.tuberculosis cell wall contains?

A

sulfatides - inhib phagosome from fusing lysosome

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56
Q

M.tuberculosis =

A

thin RODS, non-motile obligate aerobes

linear growth

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57
Q

acid-fast staining bacteria?

A

mycobacteria, nocardia

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58
Q

live-attenuated vaccines for bacteria?

A

BCG and F.tulerensis vaccines

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59
Q

Mycobacterium avium complex consists of?

A

M.avium, M.intracellulare

major opportunistic inf in AIDS pts

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60
Q

M.bovis seen w/?

A

GI tuberculosis; unpasteurized milk

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61
Q

M.leprae =

A

same as M.tuberculosis but also grows at low temps, phenolase positive

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62
Q

M.leprae infect?

A

cells of nerve sheaths

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63
Q

tuberculoid leprosy =

A

strong immune response
granulomas formed
thickened palpable nerves and 1-2 anesthethized lesions that are hypopigmented and hairless

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64
Q

lepromatous leprosy =

A

weak immune response
inflamm damage –> sensory loss at face, extremities
loss of eyebrows, saddle-nose deformity (thick nose), leonine facies (thick cheeks), infertility

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65
Q

tx of leprosy SE?

A

type 1 = DTH response –> intensified tuberculoid-like sympt; tx w/ prednisone
type 2 = immune-complex dep –> erythema nodosum leprosum; tx w/ thalidomide

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66
Q

T.pallidum =

A

spirochete
microaerophilic
sensitive to high temps

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67
Q

T.pallidum contains?

A

endoflagellum (b/w cell wall and outer membrane)

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68
Q

Giemsa stain

A 
Chlamydia
Borrelia
Ricketssiae
Trypanosomes
Plasmodium

“Certain Bugs Really Try My Patience”

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69
Q

PAS stain

A

stains GLYCOGEN, mucopolysaccharides

dx Whipple’s Dz (Tropheryma whipplei)

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70
Q

Ziehl-Neelson stain (carbolfuchsin)

A

acid-fast organisms (Nocardia, Mycobacteria)

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71
Q

India Ink

A

C.neoformans (stains CLEAR)

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72
Q

mucicarmine stain

A

C.neoformans (stains capsule RED)

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73
Q

Silver stain

A

Fungi (Pneumocystis)
Legionella
H.pylori

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74
Q

chocolate agar w/ factors V (_____), X (________) media for?

A

H.influenzae
NAD+;hematin

ENRICHMENT MEDIA

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75
Q

Thayer-Martin media contains?

A

Vancomycin (inhib Gram + org)
Polymyxin (inhib Gram - org except Neisseria)
Nystatin (inhib fungi)

SELECTIVE MEDIA!

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76
Q

Thayer-Martin media for?

A

N.gonorrheae/meningitidis

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77
Q

Bordet-Gengou (_______) agar for?

A

B.pertussis

potato!

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78
Q

cystine-tellurite plate

A

C.diphtheriae –> forms black colonies

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79
Q

Loffler’s media

A

C.diphtheriae

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80
Q

Lowenstein-Jensen agar for?

A

M.tuberculosis

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81
Q

pink colonies on MacConkey’s agar?

A

lactose-fermenting enterics!
fermentation prod acid –> turns colony pink

DIFFERENTIAL MEDIA

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82
Q

eosin-methylene blue agar?

A

E.Coli (colonies w/ green metallic sheen)

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83
Q

charcoal yeast extract agar buffered w/ _________ and used for?

A

cysteine and iron

Legionella!

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84
Q

Sabouraud’s agar

A

Fungi

“Sab’s a FUN Guy”

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85
Q

obligate aerobes

A

Nocardia
Pseudomonas aeruginosa
M.tuberculosis
Bacillus (some are facultative anaerobes)

“Nagging Pests Must Breathe”

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86
Q

obligate anaerobes

A

Clostridium
Bacteroides
Actinomyces

“anaerobes Can’t Breathe Air”

foul smelling, difficult to culture, produce gas in tissue

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87
Q

what drug class is ineffective against anaerobes?

A

Aminoglycosides (req O2 to enter)

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88
Q

obligate intracellular

A

Rickettsiae
Chlamydia

can’t make own ATP

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89
Q

facultative intracellular

A 
Salmonella
Neisseria
Brucella
Mycobacterium
Listeria
Francisella
Legionella
Yersinia pestis

“Some Nasty Bugs May Live FacultativeLY”

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90
Q

catalase + organisms

A 
Pseudomonas
Listeria
Aspergillus
Candida
E.Coli
S.aureus
Serratia

“you need PLACESS for your CATS”

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91
Q

urease + bugs

A 
Cryptococcus
H.pylori
Proteus
Ureaplasma
Nocardia
Klebsiella
S.epidermidis
S.saprophyticus
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92
Q

yellow “sulfur” granules prod by?

A

Actinomyces israelii

composed of filaments of bacteria

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93
Q

yellow pigment

A

S.aureus

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94
Q

blue-green pigment

A

Pseudomonas aeruginosa

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95
Q

red pigment

A

Serratia marcescens

96
Q

Protein A virulence factor?

A

S.aureus

binds Fc region of Ig –> prevents opsonization/phagocytosis

97
Q

IgA protease virulence factor?

A

S.pneumo, H.flu B, Neisseria (“SHiN”)

cleaves IgA –> colonize respiratory mucosa

98
Q

M protein virulence factor?

A

group A strep

prevent phagocytosis and activation of complement!

99
Q

features of exotoxin

A

genes located for in plasmid or bacteriophage;
made of polypeptide;
induces high-titer Ab (antitoxins)
ONLY staph enterotoxin not destroyed at 60 degrees C

100
Q

features of endotoxin

A

located in outer cell membrane of Gram -;
made of LPS;
causes fever, shock by release of TNF, IL-1

101
Q

superantigen cause what?

A

overwhelming release of IFN-gamma and IL-2

102
Q

3 effects of endotoxin

A 
activates macrophages (TNF, IL-1, NO)
activates complement (C3a, C5a)
activates tissue factor (coag cascade --> DIC)
103
Q

transformation?

A

take up naked DNA from environement (form recomb organism)

SHiN organisms!!

104
Q

what inhibits transformation from occurring?

A

adding deoxyribonuclease (degrades naked DNA)

105
Q

what contains genes for sex pilus and conjugation?

A

F+ plasmid

106
Q

transposition?

A

segment of DNA that can jump (excision, reintegration) from one location to another

can carry AB resistance or virulence factors

107
Q

transduction uses?

108
Q

5 bacterial toxins encoded in lysogenic phage?

A 
shigA-like toxin
Botulinum toxin
Cholera toxin
Diphtheria toxin
Erythrogenic toxin of Strep pyogenes

“ABCDE”

109
Q

beta-hemolytic bacteria

A

S.aureus
S.pyogenes
S.agalctiae
Listeria monocytogenes

“forms clear area”

110
Q

classic drugs used to tx anaerobic infections

A

metronidazole

clindamycin

111
Q

branching, filamentous Gram (+) rods w/ sulfur granules

A

Actinomyces israelii

112
Q

spore forming bacteria

A

B.cereus
B.anthracis
Clostridrium botulinum/tetani/perfringens

113
Q

see “picnics” and egg salad or chicken salad, think?

A

S.aureus - immed (1-6 hrs) vomiting/diarrhea

Salmonella - occurs 1-3 days later

114
Q

transmission from turtle

A

Salmonella

115
Q

traveller’s diarrhea

116
Q

staghorn calculi are what stones?

A

ammonium-magnesium-phosphate stones (struvite stones)

117
Q

what bug causes staghorn calculi?

118
Q

hemolysis color for alpha-hemolytic

119
Q

hemolysis color for beta-hemolytic

120
Q

water contaminated w/ rodent urine =

A

hantavirus

121
Q

Borrelia burgdorferi transmitted by, and, natural reservoir =

A

transmit by Ixodes tick (also holds Babesia)

reservoir = mouse

122
Q

BILATERAL Bell’s palsy ass w/?

A

stage 2 Lyme dz

123
Q

stage 2 Lyme dz manifestations?

A

bilateral bell’s palsy (w involved forehead);

AV nodal block

124
Q

3 biggies in atypical (interstital) pneumonia

A

Legionella pneumophila
Chlamydophila pneumoniae
Mycoplasma pneumoniae

125
Q

MRSA resistant to beta-lactams by?

A

altering penicillin-binding protein

126
Q

S.pneumo is _______ sensitive or resistant and causes?

A

optochin sensitive

Meningitis
Otitis media (in children)
Pneumonia
Sinusitis

MOPS

127
Q

normal flora of oropharynx and causes dental caries

128
Q

causes subacute bacterial endocarditis at damaged valves, and by doing what?

A

S.sanguis - sticks to damaged valves by making glycocalyx

129
Q

most commonly precedes acute PSGN

A

impetigo > pharyngitis

130
Q

S.viridans are ________ resistant or sensitive?

A

optochin resistant

131
Q

S.pyogenes is __________ sensitive or resistant?

A

bacitracin sensitive

132
Q

other S.pyogenes virulence factors

A

hyaluronate in capsule (antiphagocytic activity)
Streptolysin O
DNase (depolymerize viscous DNA in pus + disintegrate PML)
streptokinase (catalyze plasminogen –> plasmin)

133
Q

S.agalactiae is _________ resistant or sensitive and prod what factor?

A 
bacitracin resistant
CAMP factor (enlarge area of hemolysis formed by S.aureus)
134
Q

S.agalactiae positive culture requires what prophylaxis?

A

penicillin

135
Q

Enterococci (Group D strep) are resistant to what drug and grow in what?

A

resistant to penicillin G

grow in 6.5% NaCl and bile

136
Q

S.bovis causes what?

A

subacute endocarditis in COLON CANCER PTS

137
Q

C.diphtheriae acquires virulence via? has a toxin similar to? appearance in microscope?

A

bacteriophage-mediated infection w/ Tox gene –> codes for AB exotoxin;

P.aeruginosa

Gram positive rods w/ metachromatic (blue/red) granules resembling chinese letters

138
Q

spores have what in their core?

A

dipicolinic acid

139
Q

describe Clostridria species

A

Gram (+), spore-formers, obligate anaerobic bacilli

oxidase (-)

140
Q

C.difficile toxins

A

Toxin A –> enterotoxin (binds to brush border of gut –> intestinal fluid secretion and inflamm)

Toxin B –> cytotoxin (destroys cytoskeletal structure of enterocytes = kills enterocytes)

141
Q

DOC for C.difficile

A

metronidazole

2nd = oral vanco

142
Q

drugs against C.diphtheriae

A

erythromycin, penicillin; vaccine

143
Q

B.anthracis unique feature

A

polypeptide capsule containing D-glutamate

144
Q

3 toxins of anthrax

A

edema factor
lethal factor
protective antigen

145
Q

wool, goat’s hair contain spores for?

146
Q

widened mediastinum and pulm hemorrhage seen in?

A

Woolsorter’s dz (B.anthracis)

147
Q

reheated rice synd + cause/toxin

A

B.cereus –> cereulide (preformed toxin)

148
Q

able to multiply at 4 degrees C

A

L.monocytogenes

149
Q

L.monocytogenes is a ? and tx = ?

A

facultative intracellular microbe (taken up by monocytes) acquired by ingestion of unpasteurized milk/cheese and deli meats + passed on during vaginal birth
tx = ampicillin in infants/elderly/immunocomp

150
Q

Actinomyces 4 defining features

A

Gram (+) anaerobe
Not acid-fast
oral/facial abscesses (usually of mandible) draining through sinus tracts [bc part of normal oral flora]
yellow “sulfur” granules

151
Q

tx for actinomyces?

A

penicillin

152
Q

Nocardia 4 defining features

A

Gram (+) aerobe
Acid-fast
in soil, dust, vegetation
pulmonary infections in immunocompromised; cutaneous infections after trauma in immunocompetent

153
Q

Nocardia tx?

A

sulfonamides

154
Q

congenital toxoplasmosis classic triad?

A

chorioretinitis
hydrocephalus
intracranial calcifications

155
Q

cell types rich in smooth ER?

A

hepatocytes

steroid hormone-producing cells of adrenal cortex

156
Q

formation of spiral septum?

A

truncoconical swellings fuse + turn 180 degrees

neural crest cell derivative!

157
Q

underlying cause of transposition of great vessels

A

180 degree spin didn’t take place

158
Q

underlying cause of persistent truncus arteriosus

A

failure of neural crest cell migration

159
Q

congenital defects with present shunts

A 
persistent truncus arteriosus - VSD
tricuspid atresia - REQ BOTH ASD + VSD
TAPVR - ASD + sometimes PDA
ToF - VSD
transposition of great vessels - REQ ASD, VSD, OR PFO
160
Q

2 common causes of osteomyelitis in otherwise healthy children

A 
#1 = S.aureus
#2 = S.pyogenes
161
Q

osteomyelitis in sickle cell dz

A

Salmonella

162
Q

E.Coli virulence factor for UTIs?

163
Q

E.Coli virulence factor for pneumonia/neonatal meningitis?

164
Q

E.Coli virulence factor for shock?

165
Q

organisms that use fimbriae/pili to attach to tissues/cause infection

A

N.meningitidis
UTI/diarrhea-causing E.coli
B.pertussis
V.cholera

166
Q

common cause of Acute otitis externa

A

swimmer’s ear!
P.aeruginosa
S.aureus

167
Q

common cause of Acute otitis media

A

S.pneumo
nontypable H.influenzae
M.catarrhalis

168
Q

difference seen b/w bacterial and fungal/TB meningitis?

A

bacterial - increased PMNs!

fungal/TB - increased lymphocytes!

169
Q

parvoviridae

A

non enveloped, ssDNA

170
Q

what do Cowdry type A bodies look like?

A

intranuclear eosinophilic droplets (seen in HSV, CMV)

171
Q

conjugated vaccines are what?

A

polysaccharide antigen + protein

172
Q

exotoxin not destroyed at 60 degrees C is made by

173
Q

conjugation w/ F+ plasmid will

A

NOT transfer chromosomal genes

174
Q

conjugation w/ high-freq recombination cell (Hfr) will

A

transfer plasmid AND chromosomal genes

175
Q

toxins w/ genes encoded in a lysogenic phage

A 
shigA-like toxin
Botulinum toxin
Cholera toxin
Diphtheria toxin
Erythrogenic toxin of S.pyogenes

“ABCDE”

176
Q

alpha-hemolysis produces what area

A

green ring around colonies

177
Q

DOC for C.perfringens

A

metronidazole

2 - oral vanco

178
Q

DOC for GBS prophylaxis

A

intrapartum penicillin

179
Q

cutaneous anthrax

A 
black eschar (painless ulcer)
lethal factor and edema factor
180
Q

pulmonary anthrax

A

pulm hemorrhage, mediastinitis (widened, hemorrhagic mediastinum), shock

181
Q

B.cereus

A

diarrhea
cereulide (preformed toxin)
reheated rice

182
Q

L.monocytogenes

A

tumbling motility (actin)
able to multiply @4 degrees C (cold)
ampicillin for empirical meningitis tx
listeriolysin - activated in acidified phagosomes in monocytes; can lyse vacuolar membrane

183
Q

Actinomyces

A

oral/facial abscesses draining thru sinus tracts

tx = penicillin

184
Q

Nocardia

A

pulm infections in immunosupp
cutaneous infections after trauma in immunocompetant
tx = sulfonamides

185
Q

Mycobacterium 2 factors in virulent strains

A

cord factor - inhib macrophage maturation + induce release of TNF-alpha; “serpentine” looking

sulfatides (surface glycoproteins) - inhib phagolysosomal fusion

186
Q

tx for leprosy

A

tuberculoid - dapsone + rifampin 6 mo.

lepromatous - dapsone, rifampin, clofazimine 2-5 yrs

187
Q

Gram neg bacteria resistant to?

A

penicillin G and vancomycin

188
Q

N.gonorrheaoe vs. N.meningitidis

A

N.Meng - has polysacch capsule; nasopharyngeal colonization (resp/oral transmission)

189
Q

HiB vaccine unique in that

A

it contains pentose monosacch (polyribosylribitol phosphate) conjugated to diphtheria toxoid or other protein

190
Q

which bug shows up w/ hyponatremia on labs

A

L.pneumophila

191
Q

otitis externa distinguishing feature

A

granulation tissue w/in ear canal

192
Q

EHEC unique from other E.Coli in that it doesn’t

A

ferment sorbitol

193
Q

Salmonella vs Shigella

A 
Sal:
flagella
dissem hematogenously
prod hydrogen sulfide
causes monocytic response
animal reservoir (turtles)

Shigella:
cell-to-cell trans (P2P, contaminated food/water)
AB shorten duration of fecal excretion
causes PMN response

194
Q

can be transmitted from domestic animals to humans

195
Q

V.cholerae can benefit from what state

A

achlorhydia (from PPI use, ex)

196
Q

triple therapy for H.pylori

A

PPI, clarithromycin, amoxicillin/metronidazole

197
Q

H.pylori mainly colonizes where

A

gastric antrum (duodenal bulb)

198
Q

spirochetes disting factor

A

axial filaments (flagella located in diff location than others)

199
Q

leptospira

A

jaundice
photophobia w/ conjunctivitis
“question-mark” shaped

200
Q

DOC for stage 1/2 of Lyme dz

A 
doxycycline
azithromycin (in children)
201
Q

DOC for later stages of Lyme dz

A

ceftriaxone (for 28 days)

202
Q

stage 3 lyme dz

A

chronic monoarthritis/migratory polyarthritis

encephalopathy/polyneuropathy

203
Q

tertiary syphilis physical signs

A

broad-base ataxia

argyll-robertson pupil

204
Q

early sign of cong syphilis

A

snuffles (blood tinged nasal secretions)

205
Q

DOC for/cause of bacterial vaginosis

A

metronidazole

from overgrowth of certain bacteria in vagina

206
Q

R.typhi, R.prowazekii cause

A

typhus; rash starts centrally + spreads out, sparing palms/soles

207
Q

sign of Ehrlichiosis

A

granulocytes w/ berry-like inclusions in cytoplasm

208
Q

DOC for LGV

A

doxycycline

209
Q

chlamydial cell wall unique bc it

A

lacks muramic acid

210
Q

unique sequelae of Mycoplasma pneumo

A

mild anemia due to high titer of COLD agglutinins (IgM)

211
Q

histoplasmosis

A

mississippi and ohio river valleys

w/in macrophage - smaller than RBC

212
Q

blastomycosis

A

east of Mississippi river and central america
granulomatous nodules
broad-based budding yeast - same size as RBC

213
Q

coccidioidomycosis

A

southwestern US, California; San Joaquin valley fever

spherules - larger than RBC

214
Q

Tinea versicolor caused by

A

M.furfur

degrad of lipids –> prod acids –> damage melanocytes –> hypo/hyperpigmented patches (not pruritic)

215
Q

other tinea lesions usually show what histo

A

pruritic lesions w/ central clearing resembling ring

216
Q

tx for vaginal/localized candidiasis

A

nystatin (topical med)

217
Q

disseminated candidiasis predisposition =

A

decreased neutrophils

218
Q

superficial/localized candidiasis predisposition =

A

decreased T-lymphocytes

219
Q

Aspergillus can produce

A

aflatoxins (ass w/ HCC)

conidophore w/ radiating chains of spores

220
Q

C.neoformans causes what sign in brain; also, found where?

A

soap-bubble lesions;

found in soil, pidgeon droppings

221
Q

mucor/rhizopus features

A

HA, facial pain (periorbital pain)
black necrotic eschar on face (palate or nose usually)
have ketone reductase (therefore prolif in excess glucose/ketone)

222
Q

DOC for PCP

A

TMP-SMX

pentamidine, dapsone (if sulfa allergy)

223
Q

DOC for sporothrix schenckii

A

itraconazole or K iodide

224
Q

DOC for Giardia lamblia

A

metronidazole

tinidazole

225
Q

tx for asympt E.histolytica cyst passers

A

iodoquinol

226
Q

sympt of E.histolytica

A

bloody, mucous-y diarrhea
liver abscess
RUQ pain
flask-shaped ulcer if colon ruptures

227
Q

tx for Toxoplasmosis

A

sulfadiazine + pyrimethamine

228
Q

features/tx for Trypanosoma brucei gambiense/rhodesiense

A

LAD, RECURRING FEVER (due to antigenic variation), coma (late)
suramin (if blood-borne dz)
melarsoprol (for CNS penetration)

229
Q

Babesiosis features

A

fever

hemolytic anemia

230
Q

loa loa features

A

worm in conjunctiva

tx = diethylcarbamazine

231
Q

river blindness caused by

A

onchocerca volvulus;
hyperpigmented skin + blindness
tx = ivermectin

232
Q

Elephantiasis caused by/tx

A

Wuchereria bancrofti;
blocks lymphatic vessels
tx = diethylcarbamazine

233
Q

Taenia solium ingested from eggs causes

A

cysticercosis

neurocysticercosis (“swiss-cheese” appearance in brain) - tx w/ -bendazoles + dexamethasone

234
Q

diphyllobothrum latum causes

A

vit B12 def

235
Q

before removing E.granulosus cysts what do you do?

A

preinject w/ ethanol to kill cysts

236
Q

S.hematobium ass w/?

A

SCC of bladder

237
Q

C.sinenis ass w/?

A 
pigmented gallstones (from biliary tract inflamm)
cholangiocarcinoma

USMLE Step 1 Random Facts (35 decks)

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