Term
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Definition
Streptococcus pneumoniae
- alpha hemolysis
- Optochin susceptible
- aerotolerant anaerobes / obligate fermenters / some capnophiles (CO2)
- prefer BA plate |
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Term
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Definition
Corynebacterium diphtheria
(w/ L. monocytogenes)
- can show BETA hemolysis (we didn't see any)
- on Tellurite, black growth
- facultative anaerobes
- slow growth (except on Loeffler's slant) |
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Term
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Definition
Haemophilus influenzae
- requires X factor (heme) and V factor (NAD)
- therefore they must grow on CA or around Staph colonies |
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Term
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Definition
H. parainfluenzae
- requires V factor only, so will grow around V strips all the way
- can look a lot like H. influenzae
- facultative anaerobes |
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Term
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Definition
Listeria monocytogenes
- can show soft beta hemolysis (we didn't see)
- growth on tellurite is grey-black
- facultative anaerobe |
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Term
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Definition
Staphylococcus aureus w/S. epidermis
- S. aureus: beta hemolysis, larger
- S. epidermis: no hemolysis, small
- facultative anaerobes
- hardy, salt-tolerant and drying-tolerant |
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Term
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Definition
Staph. saprophyticus
- no hemolysis
- facultative anaerobe |
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Term
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Definition
Strep pyogenes (Grp A)
- beta hemolysis 100% when anaerobic incubation
- aerotolerant anaerobe
- prefers BA plate |
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Term
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Definition
Strep. agalactiae (Grp B)
- beta hemolysis
- aerotolerant anaerobe |
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Term
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Definition
- used to visualize mycobacteria, which have high MW lipid cell walls that repel gram staining, and are slow-growing
- mycobacteria show up as beaded, slender, pink rods, usually stuck together in clumps |
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Term
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Definition
- used to differentiate S. saprophyticus from S. aureus and S. epidermis
- S. saprophyticus is the only one of these that is RESISTANT |
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Term
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Definition
- used to differentiate S. aureus from S. epidermis and
S. saprophyticus
- S. aureus is POSITIVE |
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Term
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Definition
- used to differentiate between GPC
- Staph is catalase POS, and
Streps are all catalase NEG |
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Term
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Definition
- complete lysing of RBCs
- exhibited by:
- Staph. aureus
- Strep pyogenes (A) - 100% when anaerobic incub.
- Strep agalactiae (B)
- Corynebacterium diphtheria (possible)
- Listeria monocytogenes (possible)
"Beta A DiffLisAur" (Strep B & A, Diph, List, S. aureus) |
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Term
Alpha hemolysis
- what tests could you use first to distinguish them? |
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Definition
- partial RBC lysis
- exhibited by:
Strep pneumoniae
viridans Streptococci
Tests you could do:
- catalase? if NEG, it's a strep...
- optochin test? if susceptible, it could be pneumo, and you should do bile solubility to confirm. If it's resistant, it's viridans or other. You can stop here. |
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Term
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Definition
exhibited by:
- Staph. epidermidis, Staph. saprophyticus
- Enterococcus
- Neisserias & Moraxella (GC, MC, MX)
- C. pseudodiphtheria
- H. influenzae, H. parainfluenzae
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Term
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Definition
- Staph aureus (nares)
- Staph epidermidis (skin)
- Strep pneumo (10-30% of throats)
- viridans Strep
- Enterococcus (fecal)
- N. meningitidis (3-15% of URTs)
- Moraxella catarrhalis
- diphtheroids
- L. monocytogenes (environmental & intestinal)
- H. influenzae & parainfluenzae (URT)
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Term
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Definition
- Staph spp.
- C. diptheria & C. pseudo
- L. monocytogenes
- Haemophilus spp.
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Term
Incubate in increased CO2 |
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Definition
-Strep species (viridans, Pneumo, Enterococcus)
-Neisseria gonorrhea
-Neisseria meningitidis
(but not M. catarrhalis) |
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Term
Fastidious
(most to least) |
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Definition
- N. gonorrhea (CA, CO2)
- H. influenzae (X/V factor so CA), H. para (V only, still CA)
- N. meningitidis (BA, CO2)
- Strep Grp A, B, pneumo, viridans (BA preferred)
- Enterococcus (aerotolerant, but hardier)
- C. diphtheria (slow)
- Staph. aureus / epidermidis, Listeria monocytogenes
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Term
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Definition
- Staph. saprophyticus
- Enterococcus
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Term
Meningitis can be caused by... |
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Definition
- Grp B Strep (neonatal)
- Strep pneumoniae
- N. meningitidis (hematogenous)
- L. monocytogenes (rare, foodborne)
- H. influenzae
Brains Have No Problem Listening! |
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Term
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Definition
- taken from lumbar puncture / spinal tap
potential pathogens:
- Grp B strep (neonates)
- H. influenzae (young children)
- N. meningitidis (children, young adults)
- Strep pneumoniae* (older adults)
- Listeria monocytogenes (rare)
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Term
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Definition
- Staph aureus (abscesses, impetigo)
- Staph epidermis (occasional, often a contaminant but can be acq. nosocomial)
- Grp A Strep (necrotizing fasciitis; can be w/ or w/o S. aureus in erysipelas)
- Enterococcus
- diphtheroids (usually contaminants) |
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Term
Sputum specimen
- what types of cells to look for?
- what types of bacteria to look for?
- what type of contaminants to watch out for?
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Definition
- should have PMNs in bacterial pneumonia infx
LOOK FOR:
- Strep. pneumoniae
- Staph aureus (tho could be normal microbiota)
- H. influenzae(tho could be normal microbiota)
Contaminants from mouth if improper collection:
- Neisseria
- viridans Strep
- or confusion w S. aureus / H. influenzae normal microbiota |
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Term
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Definition
- used to differentiate Group A & B Strep
- Group B Strep is RESISTANT |
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Term
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Definition
- used to differentiate between Streps
- viridans Streptococci are RESISTANT
while pneumococcus is Susceptible |
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Term
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Definition
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Term
Enterococcus
- where found?
- nutrition r/t other Strep?
- infx where?
- tests? |
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Definition
- typical fecal microbiota
- they're aerotolerant anaerobes, but hardier
- can cause wound infx, sometimes UTI
- no hemolysis
- Catalase NEG (maybe pseudo)
- Bile Esculin POS (black on slant)
- NaCl 6.5% POS (color chg)
can confirm |
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Term
viridans Streptococci
- what type of specimen?
- tests? colony morphology?
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Definition
- often found in throat/mouth, so contaminates sputum specimens
- Catalase NEG
- alpha hemolytic, very tiny colonies
- Optochin resistant
- Bile Solubility - NEG
confirms it
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Term
Strep. pneumoniae
- where?
- infx?
- distinctions?
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Definition
- Throat microbiota of 10-30% healthy ppl
- Pneumonia* also Meningitis
- colonies have mucoid appearance, small, white, alpha hemolytic
- Catalase NEG
- Optochin susceptible
- to confirm do:
- Bile Solubility - POS (soluble) |
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Term
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Definition
- used to differentiate Strep pneumo from other alpha-hemolytic Strep
- put a drop of sodium deoxycholate onto isolated colonies on a plate, and incubate 15 mins.
- Strep pneumo is Bile Soluble - these colonies should lyse and disappear |
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Term
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Definition
- differentiates Grp B Strep from other Strep spp.
- positive test indicated by deep purple color after incubation and addition of ninhydrin reagent
- Grp B Strep is Sodium Hippurate POS |
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Term
Group B Streptococcus
- colony morphology
- tests
- where would you look for this |
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Definition
- incubate anaerobically for reliable beta hemolysis
- beta-hemolytic, colonies have slight orange pigmentation, small, creamy
- Catalase NEG
- Bacitracin RESISTANT
- Sodium Hippurate Hydrolysis - POS (purple)
(B is more HIP than A)
- look for in suspected neonatal meningitis |
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Term
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Definition
- Strep throat, wounds, also think of post-Strep disease
- toxins!!!
- white colonies, remain intact when pushed w/loop
- Catalase NEG
- beta hemolysis
- Bacitracin susceptible
confirm serologically |
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Term
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Definition
- few orgs are Oxidase pos (purple)
-The Neisserias
- M. catarrhalis
- tests for activity of cytochrome c oxidase (part of ETC of some bacteria)
- moisten filter paper with oxidase reagent, transfer test colony to paper and POS result is purple color change
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Term
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Definition
- SELECTIVE media containing Abx that inhibit growth of organisms that might outcompete N. gonorrhea (it's a slow grower)
- V = vancomycin (for G+)
- C = colistimethate (for G-)
- N = nystatin (for yeasts)
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Term
What organisms grow only on Chocolate agar? |
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Definition
- N. gonorrhoeae
- H. influenzae (H. flu will also grow in satellite colonies around Staph) |
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Term
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Definition
CTA slants (Cystine Trypticase soy agar)
- used to differentiate between N. gonorrhoeae,
N. meningitidis, and M. catarrhalis
- you'd use it if you had Oxidase POS organisms & you want to narrow it down
- color change from pink to yellow if positive
- Glu - GC & MC, but not MX
- Mal - MC only
- Lac - neither
- Suc - neither |
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Term
Moraxella catarrhalis
- growth and differentiation |
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Definition
- growth on NA, without CO2 incr
- sugar degradation test - NEG for all
- GC, MC and MX are all oxidase POS |
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Term
Strep pneumo
- hemolysis?
- Bile Solubility?
- Abx resistant / susceptible |
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Definition
- ALPHA hemolysis
- bile SOLUBLE
- optochin SUSCEPTIBLE |
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Term
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Definition
Urease Test
- L to R: POS, NEG, NEG or not inoc
- tests for organisms ability to produce urease; urease hydrolyzes urea and releases NH3, raising pH of medium
- pH raised = more alkaline = pink result (POS)
- we use to differentiate between GPRs:
- C. pseudodiphtheria is Urease POS
- C. diphtheria & L. monocytogenes are Urease NEG |
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Term
Enterococcus vs. Group D Strep
- tests? |
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Definition
Enterococcus is bile-esculin POS + grows in 6.5% NaCl.
Group D Strep is bile-esculin POS, but does NOT grow in NaCl. |
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Term
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Definition
Not inoculated
NG
A - C diph and L mono
AG
NC
- C. diphtheria is (A) for Glu and Mal
- C. pseudo is (NC) for all
- L. mono is (A) for Glu and Mal |
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Term
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Definition
- tests an orgs ability to reduce nitrate to nitrite, NO, N2O, N2
- nitrate A/B detect nitrite
- red color change after adding reagents A/B indicates (+) result.
- If no (+) result, add zinc, which tests for remaining nitrate
- if red color change results after adding zinc, we can conclude a (-) test
- Orgs that are (+) C. diph and C. pseudo (L. mono is negative) |
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Term
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Definition
- can be visualized using methylene blue
- spirillum volutans
- C. diphtheria |
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Term
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Definition
- used to see the capsule on bacteria
- Cryptococcus (yeast)
- Klebsiella |
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Term
Staph aureus infections?
Toxins? |
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Definition
- abscesses, wound infx, septicemia/bacteremia, pneumonia (rare)
- often nosocomial
Toxin-producing strains:
- food poisoning, TSS, SSSS |
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Term
Latex agglutination serogroups spp. |
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Definition
- Strep A/B
- N. meningitidis
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Term
C. diphtheria - where found? (is it normal) - tests? |
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Definition
- throat in lesions (few carriers, and some strains are non-toxigenic) - diptheroids themselves are very common, so lab should be looking specifically for diphtheria. - beta-hemolytic (though can't always see it) - GPR? Check for Listeria or Corynebacterium Use four different tests: - sugar ferments (Glu and Mal only w/acid) - motility (-) - urease (-) - nitrate (+) |
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Term
Listeria monocytogenes - where found? - tests? |
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Definition
- blood or possibly CSF - if seen, lab must R/O Listeria - GPR seen, colonies CAN be beta-hemolytic - Use 4 tests to distinguish between other GPR: - sugar fermentation (+) - motility (+) - urease (-) - nitrate (-) (LISTERine at NITe is NEGATIVE because you have no one to spend it on) |
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Term
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Definition
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