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Flashcards in Micro Deck (53):
1

gram positive cell membrane component that induces IL-1 and TNF

lipoteichoic acid
teichoic acids trigger Gram positive shock as the cell wall is broken down -> fever, shock, DIC

2

gram negative major surface antigen that induces IL-1 and TNF

LPS = lipopolysaccharide (endotoxin) -> Lipid A
O polysaccaride is the antigen

3

bacteremia
endocarditis
IMPETIGO
abscesses
carbuncles
FOOD POISONING
TOXIC SHOCK syndrome
Pneumonia

staph aureus

4

septicemia
endocarditis
wound infections
gram positive opportunist

staph epidermidis

5

UTI in newly sexually active young women
gram +

staph saprophyticus

6

gram + rod
normal oral flora & female genital tract
causes jaw abscesses with dental manipulation
drains by sinus tracts with yellow sulfur granules

Actinomyces

Tx: PCN

7

gram + bacillus
cutaneous (local), pulmonary (systemic), & oral/GI infections (local)
PA = protective antigen
EF = edema factor
LF = lethal factor -> inactivates MAP kinase -> cell death
PA + EF = Edema toxin
PA + LF = Lethal toxin (LT)
LT is more rapidly fatal
spores in dry soil or skins/coats of herbivores
*widened mediastinum from hemorrhage of thoracic lymph nodes in inhalation infection
cutaneous: ulcer with black eschar -> painless & necrotic

Bacillus anthracis
Tx: doxycyclin or ciprofloxacin

8

gram + rod
spore on rice cooked below boiling
nausea, vomiting, watery diarrhea (non-bloody)

Bacillus cereus
Tx: symptoms -> self-limiting
Board scenario: eating reheated fried rice

9

gram neg rod in oral flora of CATS
Causes bacillary angiomatosis (AIDS patient)
& cat-scratch disease (localized lymphadenopathy)

Bartonella henselae
Tx for bacillary angiomatosis: erythromycin or doxycycline

10

mediates adherence to indwelling catheters

glycocalyx

11

no cell wall but contain sterols

mycoplasma

12

gram neg rod
respiratory droplet spread
submucosal inflammation
Tracheal cytotoxin kills ciliated epithelial cells -> cough
whooping cough
3 stages to illness; tx with macrolides in catarrhal stage (runny nose, mild cough)
1. catarrhal (1-2 weeks)
2. paroxysmal stage (1-6 weeks) coughing +vomit
3. convalescent stage -> neuro damage or death

Bordatella pertussis
Vaccines:
DTap
Tdap -> booster

13

What stains glycogen and mucopolysaccharides?

PAS

14

used to stain Cryptococcus neoformans

India ink

15

stain for fungi

Silver stain

16

Acid-fast organisms stain

Ziehl-Neelsen (carbol fuchsin)

17

stains Chlamydia, Borrelia, Rickettsia, Trypanosomes, Plasmodium

Giemsa

18

agar used to grow fungi

Sabouraud
"Sab's a fun guy!"

19

aerobe seen in burn wounds, complications of diabetes, nosocomial pneumonia & CF pneumonias

pseudomonas aeruginosa

20

spirochete transmitted by Ixodes tick
Reservoir: mice
Intermediate host: white-tailed deer
bulls-eye rash
causes Lyme disease

Borrelia burgdorferi

Symptoms: FAKE
Facial nerve palsy
Arthritis
Kardiac block (AV block)
Erythema migrans = bulls-eye rash
Tx: doxycycline/ceftriaxone

21

Where are anaerobes normal flora?

GI tract

22

encapsulated bacteria

SHiNE SKiS
Strep pneumoniae
H flu
Neisseria meningitidis
E coli
Salmonella
Klebsiella pneumoniae
group B Strep

23

patients with Chronic Granulomatous Disease (NADPH deficiency) have recurrent infections with what type of organisms?

catalase +
Catalase degrades H2O2 before it can be converted by myeloperoxidase (bacteriocidal)
Pseudomonas
Listeria
Aspergillus
Candida
E coli
S aureus
Serratia

24

gold pigment-producing bacteria

S "aureus" mean gold

25

produces blue-green pigment

pseudomonas

26

produces red pigment

serratia marcescens
"think maraschino cherry"

27

location of genes for EXOtoxins

plasmid or bacteriophage
Ex: tetanus, botulism, diphtheria

28

overactivates adenylate cyclase by disabling Gi

B pertussis

29

MOA: bind to 30s ribosomal subunit and prevent tRNA from binding to the A site
Used to treat Lyme disease, bacillary angiomatosis, anthrax

doxycycline = TETRACYCLINE
Adverse: photosensitivity, teeth discoloration
Other: minocycline

30

comma-shaped gram neg rod
most common cause of bacterial diarrhea in US
fecal-oral transmission
dogs
contaminated meat
watery foul-smelling diarrhea that becomes BLOODY

Campylobacter jejuni

commonly precedes GBS & reactive arthritis

31

"can't see, can't pee, can't climb a tree"
rarely occurs with chlamydia infection

Reiter syndrome = reactive arthritis triad

32

treatment for chlamydia

azithromycin or doxycycline
BUT *** add ceftriaxone for gonorrhea
treat both partners

33

neonatal infections from chlamydia

conjunctivitis
pneumonia

34

Shiga-like toxin -> causes HUS

E coli (EHEC) 0157:H7 strain

35

dysentery
toxin causes enhanced cytokine release causing HUS

Shigella spp
toxin is Shiga toxin

36

pharyngitis with pseudomembranes in throat & severe lymphadenopathy

Corynebacterium diphtheriae
toxin is diphtheria toxin

37

watery diarrhea from heat-Labile toxin (LT) and heat-Stable toxin (ST)

ETEC = Enterotoxigenic E coli

38

spasticity, risus sardonicus, "lockjaw";
toxin prevents release of GABA & glycine from Renshaw cells in spinal cord (inhibitory NTs)

Clostridium tetani
Toxin: tetanospasmin

39

Floppy baby
flaccid paralysis from toxin preventing release of ACh at NMJ

Clostridium botulinum
Toxin: botulinum toxin

40

most common cause of
Meningitis
Otitis media
Pneumonia
Sinusitis

Streptococcus pneumoniae

lancet-shaped diplococci
capsule

41

resistant to optochin
live in mouth
produces dextrans which form fibrin-platelet aggregates on damaged heart valves

strep sanguinis

42

major player in dental plaque
produces acid from carbohydrate fermentation -> allows invasion -> endocarditis

strep mutans

43

pharyngitis, Impetigo, Scarlet fever, necrotizing faciitis, Rheumatic fever

Strep pyogenes (group A strep)
Note: impetigo commonly precedes glomerulonephritis

44

cold agglutinins
requires cholesterol for growth
walking pneumonia

Mycoplasma pneumoniae

45

Gram positive rods (4)

Clostridium
corynebacterium
Listeria
Bacillus
Mycobacterium (acid-fast)

46

test done for group B strep

CAMP test

47

colonize the gut
can grow in 6.5% NaCl and bile
nosocomial infection is vancomycin resistant

Enterococci = Group D strep
gamma hemolytic = no hemolysis

48

focal accumulations of virions or viral gene products

inclusion bodies

49

viruses replicate in the nucleus

DNA viruses

50

viruses replicate in the cytoplasm

RNA viruses

51

vesicular lesions of hands, feet, mouth & tongue
mild febrile illness
painful swallowing and vomiting

coxsackievirus A
The B virus can cause myocarditis and pleurodynia (devil's grip)

52

negative monospot test
sore throat
hepatitis
generalized lymphadenopathy

CMV
Most typical cause of mononucleosis is EBV. Will see + monospot test in those patients.

53

Virulence factor for mycobacteria

Cord factor
Allows to form rope like cords which means that it can cause disease
It is two mycolic acids attached to trehalose