Usmle Microbio Batch 1

Front 1

which bacterium's capsule made of D-glutamate (not polysaccharide)?

Back 1

Bacillus anthracis

Front 2

Who has IgA protease

Back 2

Neisseria, H. influenzae, Strep. pneumo

Front 3

Which bugs do NOT Gram stain well?

Back 3

(These Rascals May Microscopically Lack Color); Treponema (too thin); Rickettsia (intracellular); Myobacterium (high lipid content); Mycoplasma (no cell wall); Legionella (mostly intracellular--do Ag stain); Chlamydia (intracellular)

Front 4

Stability of exotoxin vs endotoxin

Back 4

exo--destroyed rapidly at ~60C; endo--stable at 100C for 1 hr

Front 5

Bugs with superantigens

Back 5

S.aureus (TSST-1, enterotxin); S.pyogenes (erythrogenic toxin); (and EBV??)

Front 6

which bugs have ADP ribosylating toxins?

Back 6

C.diphtheriae (EF-2); Pseudomonas (EF-2); V.cholera (AC->cAMP); e.coli (AC->cAMP and GC->cGMP); B.pertussis (inhibits Gi)

Front 7

double zone of hemolysis seen with?

Back 7

C.perfringens

Front 8

Bordet-Gengou agar for who

Back 8

Bordetella pertussis (increased blood concentration)

Front 9

What agar for Legionella?

Back 9

Charcoal yeast extract (needs Fe and cysteine)

Front 10

What agar for Neisseria?

Back 10

if sterile site--chocolate; if nonsterile (dick drip)--Thayer-Martin

Front 11

What agar for H.influenzae?

Back 11

chocolate with factor X and V

Front 12

what agar for C. perfringens?

Back 12

egg yolk (lecithinase degrades yolk ,get insoluble precipitates)

Front 13

What agar for TB?

Back 13

Lowenstein-Jenson (has lipids)

Front 14

What agar for C.diphtheria

Back 14

tellurite

Front 15

Bacitracin sensitivity test for?

Back 15

to distinguish beta hemolytic streps: Strep. pyogenes (sensitive) vs Strep agalactaie (resistant)

Front 16

Which are the alpha hemolytic streps?

Back 16

Strep pneumo, Viridans strep (distinguish on basis of bile, optochin sensitivity)

Front 17

Which bugs are beta hemolytic (green partial hemolysis)?

Back 17

Staph aureus (cat&coag+); Strep pyogenes (bacitracin sensitive); Strep agalactaie (bacitracin R); Listeria monocytogenes (tumbling, short GPR)

Front 18

How distinguish Shigella from Salmonella?

Back 18

(both GNR, non lactose fermenters); Shigella--no gas from glucose fermentation, no H2S, non motile

Front 19

how distinguish Neisserias?

Back 19

N. meningitis--ferments glucose and maltose; N. gon--ferments only glucose

Front 20

Significance of phenylenediamine agar?

Back 20

turns black if organism is oxidase positive

Front 21

Red pigmented colonies?

Back 21

think Serratia

Front 22

Quellung test

Back 22

tests for capsule. if capsule, swells

Front 23

Ag stain used for?

Back 23

Legionella, fungi, PCP

Front 24

Ziehl-Nielson stain?

Back 24

acid fast stain

Front 25

Giemsa stain best for?

Back 25

Borrelia, Plasmodium, trypanosomes, chlamydia

Front 26

Which bacterial toxins encoded by lysogenic phage?

Back 26

botulinim, cholera, diphtheria, strep pyogenes erythrogenic

Front 27

obligate aerobes?

Back 27

(Nagging Pests Must Breathe); Nocardia, Pseudomonas, M.tuberculosis, Bacillus

Front 28

Obligate anaerobes?

Back 28

Clostridium, Bacteroides, Actinomyces

Front 29

Facultative intracellular bugs?

Back 29

(Some Nasty Buds May Live FacultativeLY); Salmonella, Neisseria, Brucella, Mycobacterium, Listeria, Francisella, Legionella, Yersinia

Front 30

"safety pin"

Back 30

Persinia

Front 31

Protein A

Back 31

virulence factor in Staph aureus; binds to Fc-IgG to inhibit complement fixation and phagocytosis

Front 32

what bug assoc'd with mayonnaise, custard food poisoning?

Back 32

staph aureus (preformed toxin--starts fast, ends fast)

Front 33

4 bacterial toxins that induce cAMP?

Back 33

v.cholera toxin; B.pertussis toxin (via inhibition of Gi); E.coli heat labile toxin; B.anthracis edema factor (bacterial AC)

Front 34

treatment for Legionella

Back 34

erythromycin (macrolide, binds 23S of rRNA of 50S; acute cholestatic hepatitis in mom; increases sr[theophylline, oral coag])

Front 35

Pseudomonas tx

Back 35

aminoglycoside + extended spectrum penicillin (piperacillin, ticarcillin)

Front 36

tx for H.pylori

Back 36

bismuth + metronidazole + tetracycline/amoxicillin OR metronidazole + omeprazole + clarithromycin

Front 37

Tx for Hansen's dz

Back 37

dapsone (toxcitiy: hemolysis, methemoglobinemia)

Front 38

hepatitis + pneumonia, think?

Back 38

Q fever (Coxiella burnetii, inhaled, no rash)

Front 39

What is Weil-Felix rxn?

Back 39

assays for antiRickettsial bs which cross react with Proteus Ag; pos for typhus and RMSF

Front 40

Vectors for the rickettsial dzs

Back 40

RMSF (R.rickettsii)--dog tick Dermacentor; epidemic typhus (R.prowazekii)--human body louse; endemic typhus (R.typhi)--fleas; Q fever (C.burnetii)--aerosol

Front 41

rash on sole and palms could be?

Back 41

RMSF, syphilis, coxsackie A virus (RNA nonenveloped enterovirus)

Front 42

stages of Lyme dz?

Back 42

st1-erythema chornicum migrans, flulike sxs; st2-neurologic (Bells palsy) and heart block; st3--autoimmune migratory polyarthritis

Front 43

spherule with endospores

Back 43

Coccidioidomycosis (SW US)

Front 44

ship's wheel morphology

Back 44

Paracoccidoidomycosis (rural L.Am)

Front 45

Cladosporium werneckii cuases?

Back 45

tinea nigra; infection of keratinized layer of skin--> brownish spots (tx: salicyclic acid)

Front 46

septate hyphae, 45degrees

Back 46

Aspergillus

Front 47

nonseptate hyphae, 90degrees

Back 47

mucormycosis

Front 48

cigar shaped budding yeast in pus

Back 48

sporotrichosis, ascending lymphangitis

Front 49

acid fast cysts

Back 49

cryptosporidium

Front 50

the vector for RMSF is also the vector for what dz?

Back 50

(Dermacentor tick); also for Francisella tularensis

Front 51

Ixodes tick is vector for what dzs?

Back 51

Babesia, Lyme, Erhlichiosis

Front 52

Strep bovis bacteremia assoc'd with?

Back 52

underlying colonic malignancies

Front 53

who is CAMP test positive?

Back 53

strep agalactiae

Front 54

Whic is pyrrolidinyl arylamidase positive?

Back 54

gp D strep--enterococcus; gp A strep--strep pyogenes

Front 55

Yersinia enterocolitica usually acquired from?

Back 55

contaminated milk or pork

Front 56

How dz rickettsial dzs in lab?

Back 56

serologic analysis (ELISA) > isolation of organism

Front 57

which DNA viruses are NOT linear?

Back 57

Papovavirus (circular/supercoiled); Hepadna (circular, incomplete)

Front 58

Most DNA viruses are helical or icosahedral? what's the exception?

Back 58

icosahedral, except for Pox ("complex")

Front 59

Which RNA virus families are NOT enveloped?

Back 59

Picornavirus (Entero, Rhino, ss(+)RNA); Calcivirus (HEV, Norwalk, ss(+)RNA); Reovirus (Roto, Colorado Tick Fever, dsRNA)

Front 60

Which ss(+)RNA is helical?

Back 60

Coronavirus

Front 61

Which enveloped RNA viruses re (-)ssRNA?

Back 61

orthomyxovirus, paramyxovirus, rhabdovirus, filovirus, arenavirus, bunyavirus, deltavirus

Front 62

Which vaccines are egg-based?

Back 62

Flu, MMR, Yellow fever

Front 63

Which vaccines are KILLED?

Back 63

Salk polio, rabies, influenza, HAV

Front 64

How many serotypes in the paramyxoviruses?

Back 64

1 except for parainfluenza which has 4

Front 65

Name the dz: high fever, black vomitus, jaundice, transmitted by Aedes mosquito

Back 65

yellow fever (flavivirus, ss(+)RNA, enveloped)

Front 66

special medium for mycoplasma?

Back 66

medium with cholesterol, purines, and pyrimidines

Front 67

what are episomes?

Back 67

plasmids that have become integrated into csome by site-specific recombination--passed to every single product of binary fission

Front 68

plasmid with tra operon?

Back 68

= resistance transfer factor; believed to arise from movement of transposons w/i cells--> accumulate MDR genes into plasmids capable of mediating their own transfer by conjugation

Front 69

plumber's itch

Back 69

due to cutaneous larval migrans from dog/cat hookworms which cannot mature in host. infectious forms passed in dog/cat feces-->hazardous to crawl under house

Front 70

swimmer's itch

Back 70

itchy skin due to penetration by cercariae (larvae) of bird schistosomes (trematodes)

Front 71

treatment of choice for toxoplasma encephalitis?

Back 71

pyrmethamine+ sulfadiazine

Front 72

what Rx for tissue invasive Entamoeba histolytica?

Back 72

iodoquinol (metronidazole if no extraintestinal invasion)

Front 73

golden brown eggs with bipolar plugs?

Back 73

Trichuiria trichuria (whipworm, rectal prolapse)

Front 74

rough-shelled brown oval eggs?

Back 74

Ascaris lumbricoides

Front 75

staph impetigo vs strep impetigo?

Back 75

staph--older children, vesicular lesion; strep--younger children, weeping and oozing lesion

Front 76

most common cause of bacterial meningitis in renal transplant pt or adult with cancer?

Back 76

Listeria monocytogenes

Front 77

what are sulfatides?

Back 77

molecules elaborated by TB that allow it to survive w/i phagosomes