amtmicro813 Flashcards

1
Q

5 species with capsules:
-mucoid, antigenic/serotype

A

-Cryptococcus neoformans

-Strep/Kleb pneumo
-H.influ, N.meningitis

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2
Q

5 nonmotile

Flagella etc
Mono/Amphi/Peri…
Lopho…

A

-Kleb, Shigella

-Bacillus anthracis
-Corneybacterium
-L.mono at 35C

Flagella etc
Mono/Amphi/Peri…flagellus at one,both,all around
Lopho…tuft of flagella at a polar end

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3
Q

KB etc…
0.5 McFarland std adjust turbidity of inoculum
inoculate, wait at least 5 min but not more than 30 before putting on disks

smaller zone means too much moisture

measure diameter of outer zone, MIC is mininum inhibitory concentration

penicillin/methicillin best indicators of disk storage

agar 4.0, MH 150mm, ph 7.2

E test is MIC on a plastic triop

D test is double diffusion, looks like a D flattened zone of inhibition to clindamycin

A

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4
Q

Describe hemolysis:

alpha prime:
alpha:
beta:
gamma:

A

Describe hemolysis:

alpha prime: aplha surrounded by beta

alpha: incomplete, green

beta: complete, transparent

gamma: no hemolysis

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5
Q

QC:
dry heat oven:
autoclave/wet:

A

QC:
dry heat oven: B.subtilis

autoclave/wet: B.stearothermophilus

-dry=shorter bacillus
-wet=longer bacillus

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6
Q

7 sterilization methods…
1 most effective…
1 used if media can’t be heated…

A

6 sterilization methods…

-1 most effective…autoclave
-1 used if media can’t be heated…filtration

-boiling
-dry heat/flame
-fractionalization

-glutarldehyde: cold sterilization
-ethylene oxide gas

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7
Q

3 antiseptics: tissue

3 disinfectants: surfaces
-one best for viruses,spores,TB,fungi

A

antiseptics:
-alcohol, iodine, hydrogen peroxide

disinfectants:
-chlorine best for viruses, spores
-phenol
-quaternary ammonium

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8
Q

Smears:
-thin enough can see individual cells
-2 swabs best: culture, gram
-1 swab only: culture media first then roll swab for gram, slide isnt sterile

A

Morphology: 1
00 objective x 10 ocular=1000x

Cocci
-clusters, chains, pairs, tetrad arrangements
-diplo means pairs
-staphylo means irregular clumps/clusters

Bacilli
-cccobaccilli and fusiform baccilli arrangementes

Spirochetes

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9
Q

Stains

-METHYLENE BLUE: simple stain, only one dye

-GRAM: differential stain
-10sec each, rinse in between, air dry, oil objective
1.)crystal violet stains thick peptidoglycan wall with teichoic acid of GP, purple-blue
2.)iodine/mordant: fixes CV in GP; mordant combines with dye forms insoluble complex, fixes CV
3.)alcohol-acetone: decolorizes CV out of GN
4.)safrannin: counterstain for GN, pink-red

-WRIGHT:
*type of Romanowsky stain
*Methanol fixes the cells to the slide.
*Eosin Y is an acidic anionic dye *methylene blue is basic cationic dye
*buffer
*acid components of the cell (nucleus, cytoplasmic RNA, basophilic granules) stain blue or purple
*basic components of the cell (hemoglobin, eosinophilic granules) stain red or orange.

WRIGHT-GIESMA
-Giemsa stain is combined with the Wright’s Stain, the color brightens to a reddish-purple in the cytoplasmic granules

INDIA INK
-Cryptococcus neoformans, because of its large polysaccharide capsule, can be visualized by the India Ink stain.
Organisms that possess a polysaccharide capsule exhibit a halo around the cell against the black background created by the India Ink.
-Nigrosin
-cells negative charge repels stain

A

Acid fast stain

-ACID FAST: mycobacterium/TB
*Hard to decolorize due to mycolic acid and thus retain primary stain
*carbol fuchin, acid alcohol, methylene blue
*Pos pink, Neg blue/green

1.)Kinyoun: cold/no heat
-carbolfuschin
-phenol not heat for penetration
-MB or malachite green counter

2.)ZielNeelson: hot
-carbolfushin primary,
-heat to penetrate
-acid/ethanol to decolorize
-MB counterstain

3.)Fluorochrome:
-dye absorbs UV, emits higher wavelength
-more sensitive
-bright yellow orange, dark back
-auramine/rhodamine primary
-acid alcohol decolorizer
-K permanganate counter

YEAST/FUNGI
-Calcofluor white
-10% KOH to break down debris/mucous
-pos is bluish white flurescence

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10
Q

Most abundant NF in throat…

Most common pathogen in throat…

A

NF: alpha heme strep (viridans)

pathogen: S.pyogenes

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11
Q

Nasopharygeal swab for these 3…

Throat swab for this…

A

Nasopharygeal: upper respiratory
H.influ, N.mening, B.pertusis

Throat swab:
Strep pyogenes

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12
Q

3 GPC in clusters aerobic that are catalase+

4 GPC in chains/pairs aerobic catase -

A

3 GPC in clusters aerobic that are catalase+
-Staph, CNS (epi,sapro), micrococcus

4 GPC in chains/pairs aerobic catase -
-Strep(A pyogens,B agalactiae)
-enterococcus, group D

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13
Q

Differentiate CNS S.epi from S.sapro with…
-both cat+, coag neg

S.epi…skin
S.sapro..UTI

A

Differentiate S.epi from S.sapro with…

S.epi…suspectible to Novobiocin

S.sapro..resistant to Novobiocin

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14
Q

Grp… strep susceptible to…
How many units…

Grp…strep resistant to…

A

GrpA:
Bacitracin
0.02-0.04

GrpB: resistant to Bacitracin

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15
Q

Differentitate Grp A from GrpB strep
-both cat neg

Grp A..
-sensitive to
-1 test pos for

Grp B…
-resistant to
-2 tests are pos for

A

Group A sensitive to Bacitracin
-PYR pos

Group B resistant to Bacitracin
-CAMP, hippurate +

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16
Q

Both enterococcus and Grp D hydrolyze…

Differentiate these two with…
-enterococcus
-Grp D

A

both hydrolyze esculin

-enterococcus grows in NaCl
-Grp D doesn’t

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17
Q

What diff GPC aerobic from aerobic GNDC

GPC…
GNDC…

A

oxidase: purple
-drop reagent on colony
-rub colony filter paper, drop reagent
-rub colony on filter with reagent
*but do not use nichrome loop it will give false pos

GPC oxidase neg
GNDC oxidase pos

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18
Q

Alpha heme strep…

what diff between the two…
S.pneumo…
Viridians

A

S.pneumo:
-bile soluble, optochin susceptible

viridans:
-optochin resistant

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19
Q

Sugar fermentation…
N.gonn..
N.mening..
N.lac..
Moraxella..
-two test pos for

A

N.gonn=glucose
N.mening=glucose, maltose
N.lac=glucose,maltose, lactose

Moraxella=none
-DNase pos
-Butyrate esterase pos

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20
Q

2 genera GNDC, oxidase pos…
how to diff..

A

Neiserra, Moraxella

sugars

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21
Q

Best media for gonococci/meningcocci…
what is main agar, 3 antibiotics, additonal

A

Modified is Thayer Martin plus
-trimethoprim lactate(inhibits proteus swaming)

Thayer Martin
-enriched choc agar
-colistin, nystatin, vancomycin inhibit other bacteria/fungi
-incubate with increase CO2

Martin Lewis: better at inhibiting yeat than TM
NYC
GC-LECT
JEMBEC: transport/growth N.gonn

Chocolate agar:
-enriched, blood lysed supplies X(hemin),V(NAD)
-increased CO2
-Haemopholis/Neisseria

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22
Q

Two genera that caues pelvic inflammatory disease

A

N.gonn
-no cotton or calcium alginate swab

Chylamydia trachomatis
-no wooden shaft

best in incubate genital for 3 days

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23
Q

Betalactamase: enzyme by bacteria against beta lactam antibiotics
-do on primary isolation because plasmid coding will be lost by subculturing

-cephalosporin chromogenic color change to pink
-acidometric: turns yellow
-iodometric

A

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24
Q

SALMONELLA AND SHIGELLA
IN STOOL
-Salmonella and Shigella don’t ferment lactose
-Only Salmonella makes H2S
*bile salts to select
*all 3 differentiate LF and H2S
-H2S indicator sodium thiosulfate
*not the same H2S in TSI
(ferric amm.citrate/sulfate)

Hektoen enteric (HE):
-selects for S/S by inhibiting normal GI flora with bile salts, blue/fuschin
-nonpathogens have color
-differentiates LF
-Shigella/Salmonella don’t ferment lactose and don’t change color
-differentiates H2SH2S(NaThiosulfate,Ferric amm.citrate), Salmonella H2S black

Xylose lysine deoxycholate(XLD):
-selects S/S by inhibiting GNR/GP with deoxycholate
-Shigella doesn’t ferment xylose, sucrose, lactose
-differentiates: sugars/LF, H2S(Salmonella black)
-phenol red

Salmonella/Shigella(SS):
-selects by inhibiting other enterics with bile salts, brilliant green
-differentiates: LF, H2S

Gram negative broth:
-S/S from stools/rectal swabs
-selects for S/S by inhibiting GP with deoxycholate and citrate salts

A

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25
Q

In addition to bile salts, each of the 3 have an additional selective agent…

HE:
XLD:
SS:

A

HE: bromothymol blue, acid fuchsin

XLD: deoxycholate

SS: brilliant green

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26
Q

3 General GN selective media:
-selects for, with, if diff/what diff with/for

EMB:
MAC:
SMAC:

TSI H2S indicators, sugars, reading

A

Eosin Methylene Blue(EMB)
-urine cultures, UTI
-selects for enteric GNR with dyes
-eosin and methylene blue dye inhibit GP
-diff LF green-black to purple (E.coli has green metallic sheen)

MacConkey:
-gastroenteritis
-selects for enteric GN by inhibiting GP with bile salts and crystal violet dye
-diff LF(pink)

Sorbital MacConkey:
-selects for E.coli 0157 with sorbitol, 0157 doesn’t ferment sorbitol and is colorless

Triple sugar agar:
-mostly lactose/sucrose, some glucose
-butt=glucose, slant=sucrose/lactose
-yellow acid, pink=alkalineH2S

TSI indicatiors:
-ferric amm. citrate/sulfate
(not the same is H2S in SS media, Na thiosulfate)
-Salmonella is H2S pos

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27
Q

Agar: melts at 100, solidifies 45

4 media for GP:

SBA
CNA
PEA
SSA

A

Sheep blood agar:
-selects for nonfastidious, enriched w/blood
-diff with hemolysis/sheep blood

Colistin nalidixic acid:
-selects for GP by inhibiting GN with colistin/nalidixic acid
-sheep blood

Phenylethyl alcohol agar:
-selects for GPC,anaerobic by inhibiting enteric GNR with phenylethyl alcohol

Selective Strep Agar:
-selects for Grp A with antibiotics to suppress NF of throat
-does not different between A or B
-sheep blood

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28
Q

3 Media for Corynebacterium diptheriae…

which two are diff…what reagent…color…
which one is enrichment…enhances these 2

A

Corynebacterium diptheriae media
*tellurite inhibits NF, C.diph reduce it making it gray-black

Cysteine-tellurite blood agar
-diff w/tellurite, black

Tindale agar:
-diff w/tellurite, gray to black, brown halo

Loeffler
-enrichment for metachromatic granules and pleomorphism

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29
Q

2 media for Vibrio:

1 select/diff with…color…

A

Thiosulfate citrate bile salts(TCBS)
-diff with sucrose (cholerae is yellow)

Alkaline peptone water(APW)
-enrichment

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30
Q

2 media for Bordetella pertusis:

Best choice is….

A

Bordetella pertusis

Regan Lowe:
-charcoal agar enriched w/blooed etc

Bordet-Gengou:
-potato glycerol enriched w/blood
-cough plate, mercury droplets colonies

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31
Q

CIN agar for…colony appears…

BCYE for…has… …

HBT Tween for….

Myco:
Lowenstein-Jensen for…
Middlebrook…

Sabouraud Dextrose Agar, SDA

Slant;
LIA…
TSI…

Urea…

Broths
-Selenite
-Thio

A

CIN: YerSINia, bulls eye colorless halo
*Aero,Plesi, shigelloides

BCYE:
-buffered charcoal yeast extract
-yeast/cysteine enhance Legionella
-charcoal absorbs toxic stuff

HBT Tween: G.vaginalis
-human blood bilayer
-selects for G.vag
-diff w/hemolysis

MYCO TB:
Lowenstein jensen
-myco tb
-egg, potato, glycerol support
-malachite green inhibits
-35C, 5-10% CO2, weekly for 8 weeks

Middlebrook 7H10
-Myco TB

Sabouraud Dextrose Agar, SDA
-fungi
-low ph, 30C

SLANTS:
Lysine Iron Agar, LIA
-lysine, peptones, glucose,
-ferric amm,citrate(H2S, black)
-shows if can decarboxylate or deaminate lysine
-Pos decarboxylate butt is purple
-Pos deaminase slant is burgundy
-Cannot be positive for both

TSI triple sugar iron agar
-must be from pure culture
-isolation of GNR
-sucrose, lactose, sml glucose
-phenol red ph indicator
-H2S thisulfar,ferric amm,citrate

UREA
-utilize urea to ammonia with urease
-phenol red indicator, ph increase magenta

BROTHS:
-Selenite: enrichment for S/S, selenite inhibits
-Thio: anaerobic, decrease O2 tension

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32
Q

Campylobacter media

broth
-enrichment, subculture to campy selective agar after overnight incubation 4C

Campy BAP
-from stool
-incubate increased CO2 at 42C

A

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33
Q

Anaerobic media

-reducing agents to bind O2 like thioglycollate, cysteine
-broth tubes heated before to drive out O2
-gas paks have Na2CO3 and Na borohydride
-adding water makes H2 and CO2 for growth
-Palladium pellets catalyze the reaction

BBE
-B.fragilis, black

KVLB

CCFA
-C.difficile

Anaerobic PEA
-prevents swarming and enterobac

Chopped/cooked meat

CDC anaerobic blood agar
-hemin, cystine, k enriched

A

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34
Q

5 Gram positive rods aerobic, acronym..

1 random gram positive that is cocoid then 24hrs a rod…

A

BCLEN
-Bacillus
-Corynebacterium
-Listeria monocytogenes
-Erysipelothrix (test tube brush,occupational)
-Nocardia

Rhodococcus equi: coccus to rod 24hrs

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35
Q

BCLEN: GPR aerobic..

Bacillus…shape, motility

A

Anthracis
spore forming, bamboo pole
string of pearls, Medusa head
nonmotile

cerus:
-food poisoning

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36
Q

BCLEN: GPR aerobic:

Corynebacterium is a gram…,….

diff from L.mono with… and ….
test for toxin…

NF diptheroid…

Hospital acquired diptheroid

A

Gram positve rod, nonmotile
-chinese letters,picket fence
-pallisade, club shaped
-BabeErnst, metachromatic granules

diff with L.mono:
C.diph is nonmotile/salicin neg
C.diph has toxin, detected with Elek test

NF diphtheroid: pseudodipheriticum

Hospital acquired: jeikeium

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37
Q

BCLEN: GPR aerobic

Gram postive to gram variable coccobaccilus

Catalase pos

hippurate/camp pos

A

Listeria mono

tumbling motility 25C, cold for months
food poisoning, meningitis newborns

catalase/salicin/motility pos

*looks like GrpB Strep
-but is catalase pos

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38
Q

BCLEN: GPR aerobic

Both Corynebacterium and Listeria can be gram postive rods aerobic, how to differentiate

A

Listeria is motile and salicin pos

Corynebacterium is nonmotile and salicin neg

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39
Q

BCLEN: GPR aerobic

GPR aerobic
Fine branching/filaments, beaded
sulfur, urease pos
cannot grow with antibiotics

A

Nocardia

skin=brasil
lung=asteroides

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40
Q

GNR cause of whooping cough…
prefered media…
alternate medium…

species that is urease/oxidase pos…

A

Bordetella preferss Regan Lowe,
-will grow on Bordet-gengou

bronchiseptica is urease/oxidase pos

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41
Q

4 GNR fastidious ass with animals

-cat scratch, trench
-cat/dog, musty, bipolar
-goat/cow, undulant fever
-rabbit, tularemia

A

4 GNR fastidious ass with animals

-cat scratch, trench: Bartonella

-cat/dog, musty, bipolar: Pasteurella mul

-goat/cow, undulant fever: Brucella

-rabbit, tularemia: Franciella

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42
Q

GNR fastidious ass with goat/cow, undulant fever…

-needs CO2, inhibited by thionin
-not on fuchin
-doens’t make H2S

A

GNR fastidious ass with goat/cow, undulant fever…Brucella

-needs CO2, inhibited by thionin: arbortus

-not on fuchin: suis

-doens’t make H2S: melitensis

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43
Q

GNR fastidious…

-Pontiact fever, AC, BCYE:

-Best on Regan Lowe…two kinds….
-Whooping cough:
-urease/oxidase pos

A

-Pontiac fever, AC, BCYE: Legionella

-Best on regan lowe: Bordetella
-whooping cough: pertusis
-urease/oxidase pos:bronchisepta

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44
Q

Legionella best medium, second best/color

A

BCYE
-needs cysteine

Feeley Gorman iron cysteine, brown

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45
Q

2 GNR fastidious, slender, curved
microaerophillic…
how much of each gas

A

Campy: gull winged
Heli

85% N, 10% CO2, 5% O

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46
Q

3 GNR fastidious, faculative, GI

-rice water stools, TCBS,
string test pos reagent?

-aquatic, doesn’t grow TCBS
-now enterobacteria, doesn’t grow on TCBS

A

3 GNR fastidious, faculative, GI

Vibrio chloreae
-rice water stools, TCBS,
string test pos(0.5% Na deoxycholate)

Aeromonas
-aquatic, doesn’t grow TCBS

Pleisiomonas
-now enterobacteria, doesn’t grow on TCBS

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47
Q

GNR fastidious, slender, curved
microaerophillic…

-seagulls, 42C, darting corkskrew motility, most common cause of bacterial diarrhea

-doesn’t like 42C, stomach/peptic ulcer, urea breath test

A

GNR fastidious, slender, curved
microaerophillic…

Campy jejuni
-seagulls, 42C, darting corkskrew motility, most common cause of bacterial diarrhea:

Heli pylori
-doesn’t like 42C, stomach/peptic ulcer, urea breath test
-Skirrow agar

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48
Q

GNCB, pleomorphic
enriched chocolate, fastidious, filamentous
needs X and/or V, satellitism

-upper resp/nasopharyn swab, capsule, needs X,V
-pink eye, needs V
-NF needs mostly V
-Not NF, STD/chancroid, school of fish, needs X

A

Haemophilus:
GNCB, pleomorphic
chocolate, fastidious, filamentous
needs X and/or V, satellitism
-staph supplies V(NAD), hemoylysis releases X(hemin from agar)

influenze:
-upper resp/nasopharyn swab, capsule, needs X,V

aegypticus:
-pink eye, needs V

parainflu,hae,parahae:
-NF needs mostly V

ducreyi:
-Not NF, STD/chancroid, school of fish, needs X

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49
Q

HACEK: GNCB, Capnophillic, oral flora, endocarditis

A

Haemophilus, Aggre/actino, Cardio,
Eikinella, Kingella

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50
Q

3 main GNR nonfermenters
-oxidase pos, swimmers ear, grape
-NF skin
-cystic fibrosis/immunocomp, ammonia

A

3 main GNR nonfermenters

Pseudomonas aeruginosa:
-oxidase pos, swimmers ear, grape

Acine-tobacter
-NF skin

Stenotrophomonas maltophilia:
-cystic fibrosis/immunocomp, ammonia

other nonfermenting…
Burk, Elizabeth,Morax, Alcali

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51
Q

Nonfermentation media, oxidizers….

can see acid production due to…
indicator is…

how may tubes…etc

A

OF oxidation fermentation
-need oxygen, low peptone media
-bromthymol blue indicator
-2 tubes: one open, one covered w/oil

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52
Q

5 GN intracellular, bacterial like wall, arthropod vectors

-grows in egg yolk sacs, ticks, typhus pox
-2 with morulae in WBC, ticks
-scrub/bush typhus, mites

A

Rikettsae
5 GN intracellular, bacterial like wall, arthropod vectors

Rikettsia:
-grows in egg yolk sacs, ticks, typhus pox

Ehrlicha/Anaplasma:
-2 with morulae in WBC, ticks

Orienta:
-scrub/bush typhus, mites

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53
Q

Biochemical Reactions…

Catalase:
-break down on H2O2 to O2/H2O
-diff Staph+, Strep -
-pos is bubbles

Coagulase:
-Rapid slide: bound/clumping factor reacts with fibrinogen
-Tube: free/unbound reacts with rabbit plasma forming fibrin clot
-4hrs, 35C, extend to 24hrs if needed
-S.aureus from others

PYR
-is a substrate, N,N, reagent
-id enterococcus and grp A beta strep
-5 min, red

Bile solubility
-bile salt causes autolysis, colony disappears/flat
-Id S.pneumo
-Neg clear, Pos turbid w/in 30min

Spot oxidase
-cytochrome oxidase oxidize Kovacs reagent to purple in 10secs
-id Neisseria and Pseudo aeruginosa(pos)

A

Hippurate hydrolysis
-pos is purple

Motility
-Neg is growth along stab
-Pos is blurred stab line

Spot indole
-enzyme break down tryptophan to indole
-filter paper, aldehyde indicator, blue to green
-id E.coli
-diff Proteus

Esculin
-id Enterococci
-bile inhibits GP
-hydrolyze esculin=pos is black

Salt tolerance
-NaCl, grow in presence of
-pos is cloudy=enterococci

Phenylalaine, tryptophan deaminase
-Pos is green

Lysine iron agar: lia
-used with TSI
-enteric pathogens
-35C, 18-24hrs
-acid=yellow, alkaline=purple
-slant: lysine deaminase
-butt: lysine decarboxylase
-also H2S

Triple sugar iron/TSI/Kligler
-GNB, enterobaceriaceae, enteric
-lactose, sucrose, glucose, H2S
-35C 18-24hrs

Urea
-if have urease, hyrolyze urea to ammonia
-Pos is pink/magenta
-diff Proteus species
-id C.neoformans between other yeasts

Citrate
-use NaCitrate as sole soure of Carbon and amm,phoshate as nitrogen
-enterobacteriaceae
-bromthymol blue: green to blue

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54
Q

Enterobacteriacea are nonfastidous and…
gram…
oxidase…
ferment…
reduce…

A

gram negative
oxidase neg

ferment glucose
reduce nitrate

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55
Q

IMViC is…

1st 4 pos is color..
last one pos color…

A

Indole, Methyl red, VP all are red/pink pos

Citrate is blue

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56
Q

IMViC acrynon and genus:

++–

–++

A

PEE ++–
-Proteus, E.Coli, Edwardsella

KES –++
-Klebsiella, Enterobacter, Serratia

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57
Q

3 aminos in Decarboxylase test/acrynm…
How many tubes…

A

Decarboxy: LAO (lysine, arginine, orthinine)
4 tubes (one for each, ctrl)

58
Q

PD(phenylaline deaminase) and urease acronym

A

PD(deaminase)+ urease=PPM
-Proteus
-Providencia
-Morganella

59
Q

Urea pos acronym

A

Urea PUNCH
proteus
ureaplasma
nocardia
Cryto neo
Heli

60
Q

Nitrate reduction:
-initial pos looks like…
-add zinc pos looks like…

A

initial red, zinc clear is pos

61
Q

ONPG tests…
detects…
which organism is ONPG pos

A

slow LF
detects beta galactosidase

citrobacter

62
Q

DNAse pos is…

two DNAse pos

A

clearing around colony 0.1N HCl

m.catt, serretia

63
Q

Antigen serotyping:
O=
H=
K=

A

O=sOmatic, both salmonella, shigella

H=flah-gella, only salmonella is motile

K=Kapsule, S.typhi

64
Q

Acceptable anaerobic..

Unacceptable…

A

-bile, blood, BM, BF
-aspirates
-tissue,wound

unacceptable:
-swabs
-sputum, washings,gastric
-voided, catheterized urine
-feces

65
Q

Anaerobic gas conditions…

random fact: most clinically sig aerobes are faculative anaerobes that can grow in either

A

80-90 N
5-10 CO2
5 H

No oxygen!!!

66
Q

Anaerobic cocci:
1 GPC
1 GNC

A

Anaerobic

GPC: peptococcus
GNC: Veilonella (red fluoresence)

67
Q

Acronym for anaerobic GPR

A

Anaerobic GPR
CLAP

-Clostridium(spores)
-Lacto(vagina pH)
-Actinomyces israelli(lumpy jaw)
-Propionibacterium(acne,NF)

68
Q

2 Clostridium that have oval subterminal spores…

1 has tennis racket terminal spores..
1 has round terminal spores…

A

2 Clostridium that have oval subterminal spores…
-botulinum
-difficile

1 has tennis racket terminal spores..
-tetani

1 has round terminal spores…
-ramosum

69
Q

4 GNR anaerobic

A

-Bacteriodes fragilis (resistant to penicillan)
-Fuso
-Prevo, Porphy

70
Q

Genera that is acid fast, high lipid content,
need 5-10% CO2 at 35C

id off growth, morph, temp, biochem, light rxn, pigment

A

Myco-bacteria

71
Q

Mycobaceteria temp, gas req

NALC:
NaOH:

A

35C
5-10CO2

NALC: liquify
NaOH: digest/decontaminate

72
Q

3 Spirochetes

A

-Borrelia
*burgdorferi: most common, ixodes tick,
lyme/bulls eye/erythema chronicum migran
*recurrentis: relapsing fever

-Treponema pallidum: syphillis, darkfield/silver

-Leptospira interrogans: Weils, zoonotic/urine
-Fletchers medium

73
Q

Mycobacteria

M.TB
-respiratory
-cauliflower on LJ
-niacin and nitrate pos

M.bovis
-niacin and nitrate neg
-GI infection

M.gordonae
-takes longer 5-10days
-tap water bacilus

M.avium complex
-environmental
-lung disease, AIDs

M.leprae
-Hansen, tissue lepra cells
-armadillo
-acid fast tissue

M.fortuitum/chelonei
-only ones that grow on Mac and grow fastest <7 days

A

Mycobacteria
-increased 5-10% CO2, 35C, 3-6 weeks
-sputum first morning 3 conconsecutive days
-broncial/gastric washings
-urine, tissue
-decontaminate with NaOH and NALC liquefies

2 media:
-Middlebrook 7H11: clear
-M=mycobacterium, Middlebrook, microscopically

-Lowenstein Jensen: green
*read uncovered, if growth then read uncovered

3 stains:
-Kinyoun: cold
-Ziehl Neelsoen: hot
both carbol fuschin, acid alcohol, MB

-Fluorochrome: more sensitive
*auramine rhodamine, acid alcohol,
potassium permaganate, acridine orange

74
Q

ACID FAST CONCENTRATION/CULTURE

3-10 ml of sputum is processed and concentrated by centrifugation
* Smears can be made – Directly from processed pellet
* May increase smear sensitivity
* However, may result in less material available for NAA testing & culture – From re-suspended pellet after the addition of buffer
* Re-suspended in ~2 ml buffer; one drop for smear

Prior to heat fixing, smears should be allowed to air dry completely within the biological safety cabinet
* Acceptable methods for heat fixing
* Flame fixing by passing over flame 2–3 times for a few seconds smear side up – Avoid scorching * 2 hrs minimum at 65-75oC on an electric slide warmer
* 15 min at 80oC1 * 5% phenol in 70% EtOH for 5 min2 – also kills AFB

A

AFB tests look for FB bacteria in your sputum. Sputum is a thick mucus that is coughed up from the lungs. It is different from spit or saliva. There are four tests used to identify AFB:

AFB smear. In this test, your sputum sample is “smeared” on a glass slide and looked at under a microscope. It can provide results in 1-2 days. These results can show a possible or likely infection but cannot be used to provide a diagnosis.

AFB culture. In this test, your sample is sent to a lab to allow the cells to grow until there are enough to test. An AFB culture can positively confirm a diagnosis of TB or other mycobacterial infection. But it takes 6-8 weeks to grow enough bacteria to detect an infection.

Molecular test. In this test, your sample is tested using nucleic acid amplification (NAAT) with AFB smear and culture. The NAAT test is done directly on sputum samples and can detect TB bacteria. If there is TB bacteria, the test can also check whether the bacteria are resistant to rifampicin, a common treatment for TB. This test can be done in less than two hours.

Susceptibility test. This test is usually ordered along with an AFB culture. It is used to figure out the most effective antibiotic to treat your infection. Mycobacterium tuberculosis may be resistant to one or more of the medicines that are used to treat TB.

75
Q

Mycobacterium Leprae:
to be diagnostic needs to be from..
lepra cells are….
alternate name…

A

tissue fluid
macrophages w/acid fast bacilli
Hansens disease

76
Q

Tween 80 for what mycobacterium…
neg=
pos=

Mycobacterium test that splits phenolphthalein from triK phenolphthalein-sulfate in 2-3days…

A

Tween 80 M.kansasii
neg=amber
pos=pink

aryl-sulf-atase test

77
Q

Most common bacterial STD, pelvic inflammatory disease

obligate intracellular parasite

A

Chamydia trachomatis

78
Q

Two free living with no cell wall, not bacteria

use antisera and test inhibition of growth

A

Mycoplasma: fried egg, walking/atypical pneumonia

Ureaplasma:

79
Q

Loeffler: C.diph

Lowenstein Jensen: mycobacteria

Regan Lowe: B.pertusus

A

Loeffler: C.diph
-granules, pleomorphism

Lowenstein Jensen: mycobacteria

Regan Lowe: B.pertusus

80
Q

Parasite:
-how many collect, w/in how many days, every.. …
-Process w/in: liquid, soft, formed…
-clean/dry: no urine/h20/barium

A

-3 specimens w/in 10 days, every other day
-liquid 30min
-soft 1hr
-formed 24hrs

81
Q

Parasite stains used for

-Trichorme:
-Wrights/Giesma
-Acid fast:
-Iron Hematoxylin:
-saline:
-Iodine:

A

Parasite stains:

-Trichorme: nuclear red/purple blue back
-Wrights/Giesma
-Acid fast: spores
-Iron Hematoxylin: microfilarial sheath
-saline: motility
-Iodine: nuclear

82
Q

Preservation:

-2 for cysts,eggs, larvae
-2 for trophs
-1 for trophs, cysts for fresh stool

A

Preservation:

-2 for cysts,eggs, larvae:
-fridge, formalin, MIF

-2 for trophs:
-PVA, SAF

-1 for trophs, cysts for fresh stool:
-Schaudinns

83
Q

Sedimentation:
contains these two, four layers

A

ethylacetate: removes fat/oil but fat/debris stay in separate layer

formalin: preserves

sediment=parasites

84
Q

Concentration:

-FES: ingredients, what 4 layers

-Zinc sulfate flotation: sg

A

Concentration:

FES: ingredients, what 4 layers
-Formalin: preserves
-Ethyl acetate: removes oil/fat
-S: sedimentation (parasites)

Zinc sulfate flotation: sg
-sg 1.18, parasites float to top
-miss operculated large

85
Q

4 Genera of Protozoa

A

Ameba, Flagellates, Ciliates, Sporozoa

86
Q

Trichomonas:
-which one has undulating membrane 1/2 the length, trasmission
-which one has undulating membrane full lenth, transmission

A

vaginalis: 1/2, sexual

hominis: full, feces

87
Q

Trypanosoma:

-West…
-East…
-vector, sickness

A

Both Tse Tse fly, trypomastigote blood

Gambiense:
-West african sleeping sickness

Rhodesiense
-East african sleeping sickness

88
Q

T.cruzi:
-vector
-can be transmitted by…
-disease called…

-amastigote in…
-trypomastigote in…

A

T.cruzi:
-vector: reduvid bug
-can be transmitted by…blood transfusion
-disease called…Chagas

-amastigote in…heart
-trypomastigote in…blood

89
Q

Leismania

-Kala Azar…

-Old…

-New…

A

Leismania

-Kala Azar…dovani

-Old…tropic

-New…braziliensis

90
Q

6 sporozoa genus

A

Plasmodium, Babesia
Crytosporidium, Cyclospora, Isospora
Toxoplasma

91
Q

2 Plasmodium that infect young/large RBCs, schuffners dots

-which one has resistance in duffy neg

A

vivax: duffy neg resistance

ovale

92
Q

Plasmodium with Hmg S/G6PD resistance, banana shaped, multiple rings

A

falciparum

93
Q

Sporozoan with four maltese cross ring forms, from deer tick

A

Babesia microti

94
Q

6 Nematodes

A

Enterobius: Pinworm
Trichuris: whipworm
Strongyloides: threadworm
Nectar/ancyclo: hookworms
Ascaris: large intestine roundworm

95
Q

Microfilaria:

Which 2 spread by mosquito, elephantitis, blood:

Which 2 spread by fly
-calabar/eye swelling
-blindness, nodule

A

Microfilaria:

Which 2 spread by mosquito, elephantitis, blood: Wucheria, Brugia

Which 2 spread by fly: loa loa, onchocerca
-loa loa: calabar swelling,eye
-onchocerca: blindness, nodule

96
Q

Sheath, nuclei:

3 have sheaths:
-1 doesn’t have in tip:
-1 has 2:
-1 goes to tip:

1 doesn’t have sheath or nuclei:

A

Sheath, nuclei:

3 have sheaths:
-1 doesn’t have in tip: wucheria
-1 has 2: Brugia
-1 goes to tip: Loa loa

1 doesn’t have sheath or nuclei: onchocerca

97
Q

2 tissue nematodes:
-one with sushi, granuloma:

-one with pigs, encysted larve, muscle biopsy:

A

2 tissue nematodes:
-one with sushi, granuloma:
Aniskasis

-one with pigs, encysted larve, muscle biopsy
Trichinella spiralis

98
Q

Trematodes:

3 intestinal/liver:
1 blood/bladder:
1 lung:

A

Trematodes:

3 intestinal/liver:
-clonorchis: chinese liver
-Fascioloa hepatica: sheep liver
-F.buski: giant GI

1 blood/bladder:
-Shistosoma

1 lung:
Paragonimus westmanii

99
Q

Chinese Liver fluke…

Chinese vase/Lung fluke:

Giant intesting fluke:

Sheep liver fluke:

A

Chinese Liver fluke…Clonorchis

Chinese vase/Lung fluke: Paragonimus

Giant intesting fluke: F.buski

Sheep liver fluke: Fasciola hepatica

100
Q

Blood fluke, Shistosomes spines and location in veins…

-Sml, lateral, intestine veins:

-lrg, lateral, intestine veins:

-lrg terminal, bladder veins:

A

Blood fluke, Shistosomes spines and location in veins…

-Sml, lateral, intestine veins: japonicum

-lrg, lateral, intestine veins: mansoni

-lrg terminal, bladder veins: haematobium

101
Q

5 Cestodes/tapeworms:
ribbon like, proglottids, segmented

A

Tania
Hymenolepsis
D.latum (only operculated)
Echinococcus
D.caninum

102
Q

Names of diseases:

-cutaneous larva migrans/creeping eruption

-larva currens

-erythema chronicum migrans

-visceral larva migrans:

A

Names of diseases:

Strongyloides:
-larva currens

Borellia burgdoferi/Lyme;
-erythema chronicum migrans

Ancyclostoma braziliense
-cutaneous larva migrans/creeping eruption:

toxocara canis/cat:
-visceral larva migrans

103
Q

GPR aerobic spore forming, bamboo pole
string of pearls
nonmotile

A

B,anthracis

104
Q

Gram positve rod, nonmotile
-chinese letters,picket fence
-pallisade, club shaped

A

Corynebacterium diphtheria

105
Q

Phase where bacteria are maturing but not about to divide

A

Lag

106
Q

Plasmodium vector…

Babesia vector

A

Plasm anopheles mosquito

Babesia deer tick

107
Q

H.nana, Diminuta vector

A

Flea, beetle

108
Q

Which fastidious, gram-negative coccobacilli is often associated with trauma after human bites or fights where the skin has been broken by human teeth?

A

Eikenella corrodens is a member of the usual flora of the oral and bowel cavities. It usually occurs in mixed infections as a result of trauma, especially human bites or “clenched fist wounds”. E. corrodens is also seen in persons with poor oral hygiene, causing adult periodontitis and meningitis.

109
Q

In addition to Giardi sp, what other intestinal parasite is clinically important in the United States?

a.
Cryptosporidium sp

b.
Cyclospora sp

c.
Isospora sp

d.
Toxoplasma sp

A

Cryptosporidium sp

The classic ova and parasite diagnostic method is accurate, but technically demanding and time consuming.

Due to the high likelihood of Giardia or Cryptosporidium as the causative parasite, numbers DFA, EIA and ICT assays are available for screening tests.

110
Q

What is an example of streptococcal group test?

a.
Enzyme immunoassays

b.
Immunofluorescent assays

c.
Particle agglutination

d.
Precipitin tests

A

Particle agglutination

Streptococcal grouping tests use a form of particle agglutination in which antibodies are bound to the surface of latex beads which bind to the antigen present in a sample to produce a visible clump.

111
Q

What is a disadvantage of the zinc sulfate flotation method for separating protozoan cysts and helminth eggs in fecal specimens?
Question 177Answer

a.
Some helminth eggs do not concentrate well with this method

b.
The centrifugation times are longer

c.
The preparation is not as clean as the sediment method

d.
There are no disadvantages to the method

A

Some helminth eggs such as operculated eggs and/or very dense eggs such as unfertilized Ascaris eggs do not concentrate well with the flotation method. Their density causes them to sink instead of float.

112
Q

A gram-negative rod > 100,000 col/cc is recovered from a midstream urine. The isolate is swarming over the blood plate, produces hydrogen sulfide on TSIA, and hydrolyzes urea, indole negative and ornithine positive. What is the likely organism identification?
Question 176Answer

a.
Morganella morganii

b.
Proteus mirabilis

c.
Proteus penneri

d.
Proteus vulgaris

A

Proteus mirabilis is a commensal species in the gastrointestinal tract of humans. It is widely disseminated in the environment and recognized as an opportunistic pathogen.

Proteus vulgaris is indole positive and ornithine negative.

Proteus penneri is ornithine negative.

Morganella morganii is indole positive and H2S negative on TSIA.

113
Q

Which organism needs the X and V factors required for fastidious organisms?

A

Haemophilus spp. need the X and V factors required for fastidious organisms.

114
Q

Which organism does not usually cause disease in a host with an intact immune system, but may cause disease in a host with a compromised immune system?

a.
Community acquired infection

b.
Nosocomial infection

c.
Opportunistic pathogen

d.
Spore forming pathogen

A

Opportunistic pathogen is defined as an organism that does not usually cause disease in a person with an intact immune system, but that can cause disease when the host’s immune system has been compromised by disease or other condition that has damaged or changed the immune status of the host.

Community acquired infection
-less than 48hrs since being in healthcare

Nosocomial infection
-while receiving healthcare, 48hours after admission

115
Q

What gram positive cocci are most frequently associated with UTIs in young, sexually active females?

A

Staphylococcus saprophyticus has been associated with UTI’s in young sexually active females. This species adheres more effectively to the epithelial cells lining the urogenital tract than other coagulase-negative staphylococci.

116
Q

What kind of sample can a parasitic infection be diagnosed through the identification of eggs (ova) or larvae?

a.
Blood sample

b.
Fecal sample

c.
Nail scraping

d.
Urine sample

A

Fecal sample

The parasites are residing in the intestinal tract. Stool specimens for ova and parasite studies must be preserved or fixed immediately.

117
Q

What cells do not have a nucleus, or any membrane bound organelles such as mitochondria, and their ribosomes are a smaller size than eukaryotic ribosomes?

A

Prokaryotes:
Bacterial cells are prokaryotes and are less complex in structure than eukaryotic cells. Prokaryotes, from the Greek “before nucleus”. They lack all membrane-bound organelles.
-DNA is in a single chromosome in a nucleoid region
-peptidoglycan cell wall

Eukaryotes:
-true nucleus
-animal, plant, fungal,parasites
-membrane bound nucleus, organelles, cytoskeleton, larger ribosomes
-have mitrochondria

118
Q

How is the use of molecular assays to detect antimicrobial resistance genes limited?

a.
Genes are not responsible for most types of antimicrobial resistance

b.
Genes may be present but not expressed; presence of the gene may not reflect resistance

c.
Large numbers of genes are responsible for all clinically important resistance

d.
Researchers have not identified genes for antimicrobial resistance

A

Genes may be present but not expressed; presence of the gene may not reflect resistance

There is concern about using molecular methods to confirm resistance because of the ability of some bacteria to contain specific resistance genes that may not be expressed. The clinical significance of the presence of the resistance genes in these bacteria is questionable.

119
Q

A 20-year-old male presents to the Emergency room with heavy urethral discharge that had been present for three days. He has been sexually active with several partners and has used no contraceptives. A culture of the discharge grows a gram-negative diplococci with adjacent sides that are flattened and is oxidase positive. What is the likely organism?

A

Neisseria gonorrhoeae is a sexually transmitted, oxidase positive, gram negative diplococci that can cause urethral discharge in males and females.

*no cotton and no calcium alginate swabs, inhibit

120
Q

Thick smear used to..

Thin smear used to…

A

The thick smear is used to screen a larger volume of blood; the thin smear is used to identify the parasite because the parasites are not as distorted as with the thick smear.

121
Q

What is the process of destroying pathogenic organisms, but not necessarily all microorganisms or bacterial spores (endospores)?
Question 191Answer

a.
Antisepsis

b.
Disinfection

c.
Filtration

d.
Sterilization

A

Disinfection:
Disinfection is the process of destroying pathogenic organisms, but not necessarily all microorganisms or bacterial spores (endospores). Physical (moist or dry heat) or chemical (e.g., bleach, phenol, alcohols, aldehydes) means may be used in the process of destroying pathogenic organisms.

Antisepsis:
decreased number of microbes present on skin.
-iodine,alchol,chlorhexidine

Sterilization:
killing/destruction of ALL microbes including spores.
-heat, filtration, oxidation
-dry heat: 171C 1hr
-wet heat/autoclave: steam under pressure 121C 15lb,15min
-filtration: heat sensitive media

122
Q

Cellophane tape preparation

The correct specimen to collect for a pinworm examination is a cellophane tape preparation. This procedure involves swabbing the child’s perianal area with a tongue blade covered with cellophane tape (sticky side out). The sampling should take place first thing in the morning before the child uses the bathroom or bathes.

A

123
Q

A 70-year-old female with a previous knee injury has joint replacement surgery. The surgery goes well, and she is discharged from the hospital to a rehabilitation facility to receive post-operative care and physical therapy. One week later the incision becomes inflamed and begins oozing a discharge. A gram stain of the discharge shows many white blood cells and gram-positive cocci in clusters. The isolate recovered is a cream-yellow beta-hemolytic colony that is catalase and coagulase positive. What is the likely organism?

A

Staphylococcus aureus is a gram-positive cocci in clusters that generally yields a cream-yellow beta-hemolytic colony that is catalase and coagulase positive. Streptococcus pyogenes and Enterococcus faecalis are gram positive cocci that are catalase negative. Staphylococcus epidermidis is coagulase negative.

124
Q

Which specific bacteria, parasitic cysts and rare fungal forms contain mycolic acid in their cell wall and retain the basic dye despite acid alcohol rinsing?

A

Acid fast organisms (containing mycolic acid) resist decolorization by acid alcohol destaining and appear the color of the primary stain.

125
Q

What do specimens for parasitic identification include?

a.
Hair, nails, stool, urine, and sputum

b.
Hair, stool, urine, bone marrow, and sputum

c.
Stool, urine, blood, sputum, and tissue biopsies

d.
Tissue biopsies, cartilage, hair, nail, and urine

A

Stool, urine, blood, sputum, tissue biopsies

Specimens for parasite identification come primarily from the intestinal tract, urogenital tract, or prostatic secretions. Specimens can also come from sputum, CSF, or biopsy material from tissues. Malarial parasites can be seen in blood.

Any identification process first depends on correct specimen (stool, urine, blood, sputum, tissue biopsies) collection and adequate fixation.

126
Q

Which four groups can most bacteria be divided into based on gram stain results?

a.
Gram positive bacilli, gram positive cocci, gram positive tetrads, and gram negative bacilli

b.
Gram positive bacilli, gram negative bacilli, gram positive clusters, and gram negative chains

c.
Gram positive bacilli, gram negative bacilli, gram positive cocci, and gram negative cocci

d.
Gram variable bacilli, gram positive diplococci, gram negative rods, and gram positive cocci

A

Gram positive bacilli, gram negative bacilli, gram positive cocci, and gram negative cocci

Tetrads, diplococci, clusters, and chains are descriptions of cellular arrangements not basic shapes. Variable indicates an indistinct staining reaction.

127
Q

When should the concentration of fecal materials be included?

a.
Intestinal formalin

b.
Intestinal ova

c.
Ova and parasite examination

d.
Thick and thin smears

A

Ova and parasite examination

Concentration procedures allow the visualization of small numbers of parasitic organisms that may be missed if only a direct mount is observed.

Various concentration procedures are used, most often sedimentation or floatation techniques.

128
Q

What kind of insects belong to the phylum Arthropoda group?

A

The phylum Arthropoda includes insects, spiders, mites, and ticks. Members of this phylum are a subgroup of parasites and are invertebrates.

129
Q

What gram negative rod is associated with lobar pneumonia in hospitalized patients?

A

Klebsiella pneumoniae is a frequent cause of lower respiratory tract infections among hospitalized patients.

130
Q

What is the etiologic agent in Lyme disease?

A

Diagnosis of Lyme disease depends on finding antibodies in the serum or spinal fluid. The etiologic agent is the bacterium Borrelia burgdorferi.

131
Q

A 10-year-old child presents to his primary care physician with a complaint of severe ear pain. The child had been swimming in the lake several days earlier. The culture from the ear grew a gram-negative rod with a grapelike odor. The colonies were flat and spreading with rough edge and a metallic sheen. It was indole negative and oxidase positive. What is the likely organism?

A

The organism is likely Pseudomonas aeruginosa. Pseudomonas is commonly found in fresh water. P. aeruginosa produce a grape like odor, are oxidase-positive and indole negative.

132
Q

What concentration of oxygen is required for the growth of obligate anaerobic organisms?

A

0% oxygen

Obligate anaerobes must be grown in an atmosphere either devoid of oxygen or with significantly reduced oxygen content.

133
Q

What nutrients in chocolate agar enable organisms to grow on this media but are unable to grow on blood agar?

A

Hemin (X) and nicotinamide adenine dinucleotide (V) factors

Chocolate agar contains lysed red cells which release hemoglobin, hemin (X) and nicotinamide adenine dinucleotide (V) factors.

134
Q

What are the most common causes of bacterial conjunctivitis in children?

a.
Haemophilus influenzae andStreptococcus pneumoniae

b.
Herpes simplex and Varicella zoster

c.
Propionibacterium acnes and Alpha-hemolytic streptococci

d.
Staphylococcus epidermidis and Lactobacillus spp.

A

Haemophilus influenzae and Streptococcus pneumoniae are common causes of bacterial conjunctivitis in children.

Staphylococcus epidermidis, Lactobacillus spp., Propionibacterium acnes and alpha-hemolytic streptococci in small numbers are normal flora of the conjunctival sac.

Herpes simplex and Varicella zoster are viral infections.

135
Q

pshychophiles:
-0-20C
-cold

mesophilic:
-moderate temp 30-37
-most pathogenic bacteria,
Ecoli, Salmonella

thermophilic:
-thrive in high temp, 50-60C
-not pathogenic cuz can’t grow at body temp

hyperthermophilic:
-80-120C

A

Incubators

Most pathogens:
35C host temp, 3-5% CO2, humidified
-Can use candle jar for CO2, only white unsented candles

Fungi:
30C

Campylobacter:
42C

136
Q

Culturing specimens/processing/planting/rejection…

*don’t refrigerate spinal, anaerobic, GC
*no dry swabs

Stool;
-lots of NF
-w/in 2hrs
-Salmonella, shigella
-Campy, Clos diff
-Vibrio, Yersinia
-Sero type S/S, E.coli
-Direct detect/molecular C.difficile etc

Urine:
-bladder normally sterile
-clean catch mid stream
-first morning more concentrated
-process in 1hr or fridge 24hrs
-<10 epis
->100,000 sig if asymptomatic
->1,000 if symptomatic male
-UTI: nitrite, leukocyte esterase, usually Ecoli
-Can be Proetus, Kleb, enterobac,Pseudo
-Gram:centrifuge, 1 drop, 20 fields, 1 organism per field

Catheter tip/intravenous:
Indicate source of sepsis or infected indwelling arterial/venous catheter
-For optimal culture results, transport specimen to the laboratory within 2 hours
-Foley from tubing not bag

Urethral/cervical/gynecological:
-No wood shaft on Chlamydia
-No cotton/calcium alginate on Neisseria
-swab to remove purulent, 2nd swab vigorously swabbing
-cell culture for Chlyamydiae
-NAT hybridization
-Trich wet mt, fungal/yeast KOH
-Bacterial vaginosis: clue cells, gvb

IUD:
-Sterile container
-Store and transport room temperature, preferably within 8 hours of collection.
-Actinomyces sp

A

Culturing specimens/processing/planting/rejection…

Blood:
-sterile collection in nutrient broth media b4 fever
-70% alcohol, iodine, alcohol rinse
-2-3 sets 24hrs
-1:5 to 1:10 dilution blood to broth
-10ml adults, 5ml kids
-can use ARD for antibiotic removal
-6 to 18hrs 35C
-blind subculture: bottles subculture to medium even if growth not visible
-smear made
-checked visually 1xday for a week
-growth: hemolysis, gas bubbles, turbidity, colonies
-Automated Bactec: incubated, rocking, measures CO2 made by bacteria, gas permeable sensors use fluorescence to detect CO2
-S.aureaus, CNS, Strep
-Enterococcus, Enterobac, P.aeruginosa
-Yeast(candida, crypto)

Wound/abcess:
-Eswab: 48 hours, refrigerated or ambient
-Sterile cup: 24 hours refrigerated

Tissue:
-Tissue not in formalin
-Sterile screw capped vial, anaerobic culture transport, bacterial culture transport swab with media, or sterile cup
-RT

CSF:
-sterile tubes
-centrifuged if >1ml, 5/10ml best
-S.pneumo, N.mening, H.flue
-E.coli, L.mono
-Newborns: Grp B, L.mono, E.coli
-Kids/young: S.pneumo, H.influ, N.mening
-Old: S.pneumo, L.mono
-Acute meningitis: >1000 WBC, segs, decreased glucose, increased protein
-Aseptic: 100-500 wbc, lymphs, normal to slight decrease glucose, increase protein

137
Q

Respiratory:
-sputum 1st morning, deep coughing, avoid saliva
-not saliva
-gram stain first
-<10 epi, >25PMNs/lpf best
-contamination if gram stained shows >10 eips/lpf

Lower respiratory
-sputum, bronch wash, aspirate, lavage, brush
-S.pneumo, H.influ
-Mycoplasma pneu, Legionella, M.TB

Throat:
-upper respiratory swab for throat culture group A beta strep
-sore throat/pharyngitis can lead to scarlet fever, rheumatic fever, or acute glomerulonephritis
-2 steriles swabs: one rapid, other sent out if neg

A

More Strep/Throat…

Rapid strep antigen detection
1.)enzyme immunoassay
2.)latex agglutionatin
3.)optical immunoassay:
-Strep A OIA
-light reflectance, appear diff color
-need to extract grp A specific carb antigen with enzyme or acid

Strep A,B,C,F,G serology
-extract strep antigen, put on slide with specific latex coated ab=agg

Culture SBA
-pharygeal area
-beta hemolysis

Other GrpA beta
-PYR +
-Bacitracin 0.04 suspectible

*Mostly Strep A in throat but may see S.pneumo
-alpha heme
-optochin suspectible
-bile soluble

138
Q

Normal Flora/pathogens

Sterile normally:
-CSF, urinary tract, blood, transtrachial aspirate/lung tissue

CSF
-sterile
-H.influ, N.menin, cryto

BLOOD
-sterile
-contaminants: micrococcus, CNS, alpa strep

THROAT, OROPHARNX
-NF: alpha strep, staph, Neiss
-Pathogens: Grp A strep, H.influ, B.pertusis

LOWER RESPIRATORY/SPUTUM
Pathogens:
-H.influ, S.pneumo,Kleb pneumo
-S.aureuas
-Myco TB/pneumo, Legionella, Fungi

Transtrachial Aspirate, lung tisse
-Sterile normally
-Pathogen: anaerobe

A

Normal flora/pathogens

URINARY TRACT
-Sterile
-Pathogens: Ecoli, GNR

GENITAL
-Normal: CNS, dip, lacto
-pathogens: N.gonn, Clam trac, Tric vag, G.vag(clue), Tre pall(darkfield), Grp B strep in pregant, Herpes

EYE:
-NF: alpha, staph, neiss
-Pathogens: Chlamydia, N.gonn
-Mostly in newborns

EAR
-pathogens:
Pseu.aeru:swimmers ear
H.influ/S.pneu: otis media

COLON
-profuse NF
-S/S, campy jejuni, vibrio
-C.difficile, Yersinia enter

GASTRIC
-pathogen: H.pylori: urease

SUPERFICIAL WOUND
-S.aureus, Grp A strep
-Pseu aeru

DEEP WOUND/ABCESS
-anaerobe, aerobe

139
Q

4 BioSAFETY levels

1: well known, do not usually cause disease in healthy, minimal hazard (B.subtilis)

2: routine specimens shigella, HIV, Salmonella

3: not usually encountered routine, Myco TB, arbovirus, arenavirus, mold stages systemic fungi, BSC/protective wear

4: not found in routine, exotic, highly controlled, ebola, arboviruses

*air goes from low risk to high risk

A

140
Q

Microscopic morphology;

Pairs and Clusters:
-S.aureus, CNS

Pairs and Chains:
-Group A,B,C,F,G beta hemolytic strep
-Viridians strep
-Enterococci

Lancet shaped, pairs/chains, halo due to capsule
-S.pneumo

A

Macroscopic/Colony morph

Staph aureus
-med to lrge, creamy, beta

CNS
-sml-med, no pigment, gamma

Group A,B,C,F,G beta strep
-mostly small gray white, beta

Strep pneumo
-sml, glistening, mucoid, convex, alpha

Viridans strep
-pinpoint, alpha

Enterococcus
-small, gamma

141
Q

Micro QC:

Media: CLSI Clinical and Lab Stds Institute/NCCLS
-performance testing: checking media with cultures of known stock microbes
-Exempt has QC failure rate of less than 0.5%
-Nonexempt more than 0.5%

DAILY
-Equipment temps
-CO2, reagent pos/neg ctrl

WEEKLY
-Autoclave: spore test
moist heat w/B.stearo
dry heat with B.subtilis
-Antimicrobial tests: subculturing, disk diffusion
-Gram stain ctrl slide Ecoli,S.aureaus

QUARTERLY/4x yr
-microscope

6MTHS
-Centrifuge rpm/speed

Annually
-Balance, BSC

AS NEEDED
-Gas pack for anaerobic methylene blue strip, O2 is blue
-thermometers: ref therm
-Insturment logs

MEDIA
-exempt from retesting if bought from CLSI manufacteer
-retest CHOC for Neis,campy
-Procedure manual reviewed/signed annually, kept 2yrs if obsolete
-compentency on hire/yearly
-Proficiency 80%

A

Culturing:

Primary: dilution streak to get isolated cultures

Subculture: mixed, separate diff types

Pure culture: several colonies from a single colony, a single cell
-grow by binary fission, a cell divides to make 2 daughters

Culture: the growth of microbes on artificial media

Culture medium: mix of nutrients which microbes is grown

Agar: seaweed extract

Microbe req:
-most are faculative anaerobes
-48hrs 35C
-ph 6.5-7.5 neutral
-moisture for metabolic rxns
-3-5% CO2
-store in fridge 4C