Identification en bactériologie Flashcards
Donnez le résultat sur TSI pour S. typhi
K/A/H2S faible + (moustache)/Gaz -
Donnez les résultats de l’antigène O et Vi pour S.typhi.
O = D9 ou D12
Vi = positif
In what Salmonella species the heat labile capsular Vi antigen can be detected?
Mainly in S.typhi and S.paratyphi C
What are the 3 species in the S.aureus complex?
- S.aureus
- S.argenteus
- S. schweitzeri
Prélèvement d’un liquide articulaire, BGP (sur la photo il semblait facilement décolorable), catalase +, indole +
Cutibacterium acnes
Nommez 3 BGN entéropathogènes au genre qui sont aérobiques, oxydase (+) et B-hémol
- Vibrio (fluvialis, mimicus et parfois cholerae)
- Aeromonas
- Grimontia (Grimontia hollisae est le seul “vibrio” qui ne pousse pas sur TCBS, il est beta-hémol et immobile)
M35 - which organisms can resemble Brucella on plates and are also urease positive?
- Bordetella bronchiseptica
- Oligella ureolytica
What temperature should be used for Campylobacter recovery?
42°C
M35 : Presence of a rosette structure (thin pleomorphic gram negative) in Gram stains made from positive blood culture broths is virtually pathognomonic for what organism?
Cardiobacterium hominis
M35 : This is the only MacConkey-negative,
catalase-negative, oxidase-positive, gram-negative rod that is ornithine positive.
Eikenella corrodens
M35 : Which of the HACEK organisms grows very well on blood sheep agar, producing large B-hemolytic colonies?
Kingella kingae
M35 : For gram-negative diplococci that are oxidase and catalase positive, and grow on both chocolate and BAP, what kind of rapid test (3) will identify M. catarrhalis?
- Positive rapid butyrate esterase
- Positive tributyrin test
- Positive indoxyl acetate test
M35 : What is the expected reaction for N.meningitidis for
1. γ-glutamyl-aminopeptidase
2. ß-galactosidase
- Positive
- Negative
M35 : What is the expected reaction for N.lactamica for
1. γ-glutamyl-aminopeptidase
2. ß-galactosidase
- Negative
- Positive (LACTamica - B-gaLACTosidase)
M35 : Describe indole reaction for -
1. P.mirabilis
2. P.vulgaris
- Negative
- Positive
M35 : Rare Aeromonas isolates may resemble
P. aeruginosa (lacking the typical smell), but can be distinguished by what test?
Indole test (Aeromonas will be positive, Pseudomonas negative)
M35 : Describe the expected reactions for Brucella
1. Oxidase
2. Catalase
3. MacConkey
4. Urea
5. Indole
6. Hemolysis on BAP
- Oxidase +
- Catalase +
- MacConkey No growth
- Urea +
- Indole -
- Hemolysis on BAP -
M35 : Describe the expected reactions for Campylobacter
1. Oxidase
2. Catalase
3. Motility
4. Hippurate reaction for C.jenuni
5. Indoxyl acetate reaction for C.jenuni/coli
- Oxidase +
- Catalase +
- Motility : Darting
- Hippurate reaction for C.jenuni : +(other species are negative)
- Indoxyl acetate reaction for C.jenuni/coli : +
M35 : Describe gram stain for Cadiobacterium hominis
Pleomorphic thin gram-negative rod
M35 : Describe the expected reactions for Cardiobacterium hominis
1. Oxidase
2. Catalase
3. Growth on MacConkey
4. Indole
5. Hemolysis on BAP
6. Nitrate
- Oxidase +
- Catalase -
- Growth on MacConkey -
- Indole +
- Hemolysis on BAP -
- Nitrate - (VS Pasteurella bettyae nitrate +)
M35 : Describe the expected reactions for Eikenella corrodens
1. Oxidase
2. Catalase
3. Indole
4. Hemolysis on BAP
5. Smell
6. ODC
- Oxidase +
- Catalase -
- Indole -
- Hemolysis on BAP -
- Smell : Bleach
- ODC +
M35 : Describe gram stain for Eikenella corrodens
Small gram negative rods
M35 : Describe the expected reactions for Escherichia coli
1. Oxidase
2. Indole
3. Hemolysis on BAP
4. PYR
5. MUG
- Oxidase -
- Indole +
- Hemolysis on BAP +
- PYR -
- MUG +
M35 : Describe the expected reactions for Francisella tularensis
1. Oxidase
2. Catalase
3. Growth on BAP
4. Satellites around S.aureus streak
5. B-lactamase
- Oxidase -
- Catalase - or weak
- Growth on BAP -
- Satellites around S.aureus streak on BAP -
- B-lactamase +
M35 : Describe the expected reactions for H.influenzae
1. Growth on BAP
2. Satellites around S.aureus streak
3. ALA test
- Growth on BAP -
- Satellites around S.aureus streak +
- ALA test -
M35 : Describe gram stain for Kingella kingae
Gram-negative coccoid rod
M35 : Describe the expected reactions for Kingella kingae
1. Oxidase
2. Catalase
3. Growth on MacConkey
4. Hemolysis on BAP
- Oxidase +
- Catalase -
- Growth on MacConkey -
- Hemolysis on BAP +
M35 : What test can help differentiate S.schleiferi and S.lugdunensis (both slide coagulase positive) from S.aureus?
S.chleiferi and S.lugdunensis are both strong PYR positive, S.aureus is PYR negative or weak reaction
M35 : Describe the expected reactions for S.lugdunensis
- Catalase
- Tube coagulase
- PYR
- Polymyxin B susceptibility
- Rapid ornithine
- Slide coagulase
- Catalase +
- Tube coagulase -
- PYR +
- Polymyxin B susceptibility : resistant
- Rapid ornithine +
- Slide coagulase +/clumping
M35 : Describe the expected reactions for Enterococcus
- Catalase
- Colony morphology on BAP
- PYR
- LAP
- Catalase -
- Colony morphology on BAP : Usually non-hemolytic, > 1mm
- PYR +
- LAP + ONLY required if alpha-hemolytic colony
M35 : Describe the expected reactions for Aerococcus viridans
- Gram stain
- Catalase
- Hemolysis on BAP
- PYR
- LAP
- Gram stain : GPC in tetrads and clusters
- Catalase -
- Hemolysis on BAP : alpha
- PYR +
- LAP -
M35 : Describe the expected reactions for Listeria monocytogenes
- Gram stain
- Catalase
- Hemolysis on BAP
- Motility pattern
- Hippurate
- Gram stain : tiny gram positive rod
- Catalase +
- Hemolysis on BAP : B-hemolytic, narrow zone
- Motility pattern : tumbling at room temp, non motile at 35
- Hippurate +
M35 : Describe the expected reactions for S.agalactiae
- Catalase
- Hemolysis on BAP
- Hippurate
- CAMP
- Lancefield group agglutination
- Catalase -
- Hemolysis on BAP : B-hemolytic, small zone
- Hippurate + ONLY if B-hemol strain
- CAMP +
- Lancefield group agglutination : B
M35 : Describe the expected reactions for S.anginosus group
- Catalase
- Colony morphology
- Odor
- Lancefield group agglutination
- Catalase -
- Colony morphology : <0.5mm diameter with variable hemolysis
- Odor : butterscotch
- Lancefield group agglutination : always group F, sometimes A, C, G
M35 : Describe the expected reactions for S.pneumoniae
- Gram stain
- Catalase
- Hemolysis on BAP
- Bile solubility
- Gram stain : GPC lancet shaped cocci in pairs
- Catalase -
- Hemolysis on BAP : alpha hemolysis
- Bile solubility positive
M35 : Describe the expected reactions for S.pyogenes
- Catalase
- PYR
- Hemolysis on BAP
- Colony type
- Lancefield group agglutination
- Catalase -
- PYR +
- Hemolysis on BAP : narrow B-hemol
- Colony type : always >0.5mm
- Lancefield group agglutination : A
M35 : Describe the expected reactions for S.viridans
- Catalase
- Hemolysis on BAP
- PYR
- LAP
- Bile solubility
- Catalase -
- Hemolysis on BAP : alpha or non hemol
- PYR -
- LAP +
- Bile solubility -
M35 : name 5 pathogens that can look like S.viridans on agars
- Pediococcus
- Leuconostoc
- Aerococcus
- Granulicatella
- Abiotrophia
M35 anaerobes gram negatives : Large (>1 mm diameter), convex colonies on anaerobic blood agar (eg Brucella agar) exhibiting similar-sized dark (gray or black) colonies on BBE, and seen as regular gram-negative rods on Gram stain, are identified as
Bacteroides fragilis group
M35 anaerobes gram negatives : Breadcrumb or opalescent colonies on aBAP that fail to grow on BBE; are spot indole positive; and exhibit thin, pointed, fusiform cells on Gram stain are identified as
F. nucleatum
M35 anaerobes gram negatives : Small (<1 mm diameter), translucent colonies on aBAP with corresponding tiny colonies on BBE after at least 48 hours incubation, often displaying a black dot in the center of the colony due to H2S production that are strongly catalase positive are identified as
Bilophila wadsworthia
M35 anaerobes gram negatives : On aBAPs and LKV, black-pigmented colonies (or those that fluoresce brick-red under long-wave ultraviolet light) with corresponding small, translucent or opaque colonies that consist of small
coccobacilli are identified as ___________. If they are spot indole positive, they can be identified as
_____________.
- Prevotella spp
- Prevotella intermedia
M35 anaerobes gram negatives : On aBAPs, black-pigmented colonies (or those that fluoresce brick-red under long-wave ultraviolet [UV] light) with corresponding small, translucent or opaque colonies that consist of small coccobacilli, no growth on LKV and indole positive are identified as
Porphyromonas
M35 anaerobes gram negatives : Flat, transparent colonies that pit the agar, are catalase negative, urease positive,
and fail to grow on BBE are
Bacteroides ureolyticus
M35 anaerobes gram negatives : Small (0.5- to 1-mm diameter) transparent-to-opaque colonies on aBAP that fluoresce red under UV light, fail to grow on BBE, and exhibit tiny, gram-negative diplococci on Gram stain are
Veillonella spp.
M35 anaerobes gram positive : Organisms with large (>2 mm diameter), irregular colonies exhibiting a double zone of beta hemolysis on aBAP; no growth on BBE; catalase negative; and large, boxcar-shaped, blunt-ended, gram-positive or gram-variable cells without spores on Gram stain are
Clostridium perfringens.
M35 anaerobes gram positive : An anaerobic organism that shows smoothly swarming growth over the surface of the aBAP that is negative for spot indole and catalase and displays thin gram-positive rods with swollen, subterminal spores on Gram stain is
C. septicum
M35 anaerobes gram positive : An anaerobic organism exhibiting slowly moving swarming
growth that is spot indole positive, catalase negative, and whose gram-positive cells exhibit swollen terminal spores (tennis racquet shaped) is
C. tetani
M35 anaerobes gram positive : Another swarming Clostridium species with serpentine-edged colonies and slowly spreading growth that is spot indole and rapid urease positive, catalase negative, with subterminal spores is
C.sordellii
Organisms with small (approximately 1 mm to 2 mm diameter), enamel-white, opaque colonies on aBAP that fail to grow on BBE, are spot indole positive, catalase positive, and reveal pleomorphic, coryneform rods on Gram stain are
Cutibacterium acnes
Nommer 3 Streptococcus, autre que le S. pyogenes, qui sont PYR +
S. porcinus
S. pseudoporcinus
S. iniae
Nommer 2 Streptococcus autre que le S. pyogenes, qui peuvent agglutiner dans le groupe A de Lancefield
S. anginosus group
S. dysgalactiae subsp. equisimilis
Nommer des tests biochimiques permettant de différencier le Listeria et l’Erysipelothrix (5)
Catalase (Listeria + / Erysipelothrix -)
H2S (Listeria - / Erysipelothrix +)
Esculine (Listeria + / Erysipelothrix -)
CAMP (Listeria + / Erysipelothrix -)
Mobilité (Listeria + / Erysipelothrix -)
Quels sont les géloses sélectives pour N.gonorrhoeae?
o Thayer-Martin : Chocolate agar + Vancomycin + Colistin + Nystatin
o Modified Thayer-Martin : Same as above + TMP to prevent swarming Proteus
o Martin-Lewis : Same as above, but has anisomycin instead of nystatin, which has increased activity against C.albicans. Also has higher concentrations of vancomycin.
o GC-Lect Agar : Additional lincomycin provides further control against Capnocytophaga species and vancomycin resistant gram positive. Is a good agar to inhibit oropharyngeal flora.
o NY city agar : Clear peptone-corn starch agar containing yeast dialysate, citrated horse plasma, lysed horse erythrocytes. Contains vancomycin, colistin, amphotericin-B and TMP.
À noter que N. meningitidis peut tout de même pousser sur ces milieux
3 tests qui permettent de différencier P.aeruginosa des autres Pseudomonas.
-P.aeruginosa est pyocyanine positif
-P.aeruginosa croit at 42°C
-P.aeruginosa hydrolyse l’acétamide
Principale façon de différencier Campylobacter de Arcobacter?
Arcobacter poussera seulement à 25-37°, ne poussera pas à 42° comme Campylobacter
Quelle bactérie sera A/A au TSI mais K/A sur Kligler?
Yersinia enterocolitica
Nomme 3 GPB non embranchés, aérobiques et catalase neg.
- Erysipelothrix
- Arcanobacterium
- Trueperella
Quels sont les tests pour différencier C. diphtheriae de C. ulcerans et C. pseudotuberculosis?
C.diphtheriae nitrate reduction positive (vs non pour les 2 autres)
C. ulcerans et C. pseudotuberculosis CAMP inhibition et urée positive (vs négatif pour C.diphtheriae)
Bactéries avec un reverse CAMP (avec strie de S.agalactiae) positif (2)
C.perfringens
Arcanobacterium haemolyticum (peut aussi faire un CAMP inhibé)
CBGN oxydase +, catalase +, ODC +, indol +, McConkey-
Pasteurella multocida (similar appearance to Brucella, but is indole positive and urease negative, Brucella is indole neg and urease pos)
Nommez 3 géloses pour culture de Bordetella.
Regan-Lowe agar, Bordet-Gengou agar, and Stainer- Scholte synthetic medium
4 espèces de Vibrio qui peuvent être BH
- V.cholera
- V.fluvialis
- V.mimicus
- V.damsela
Quelles sont les espèces dans le Enterobacter cloacae complex?
Enterobacter cloacae, Enterobacter asburiae, Enterobacter hormaechei, Enterobacter kobei, Enterobacter ludwigii
Quels Gram - anaérobes sont Indole + ? (3)
F. nucleatum
Porphyromonas spp.
Prevotella intermedia
Quels Gram + anaérobes sont Indole + ? (3)
C. sordellii
C. tetani
C. acnes
Peptostreptococcus
Quels sont les résultats attendus pour les disques de K, V et C pour les B. frag?
R
R
R
Quels sont les résultats attendus pour les disques de K, V et C pour les Fusobacterium spp?
S
R
S
Quels sont les résultats attendus pour les disques de K, V et C pour les Veillonella spp?
S
R
S
Quels sont les résultats attendus pour les disques de K, V et C pour les Porphyromonas spp?
R
S
R
Quelles bactéries ana sont R à la bile 20% ?
B. frag groupe
Bilophila wadsworthia
F. mortiferum
F. varium
Parabacteroides spp
Odoribacter denitrificans
Quels Clostridium sont aérotolérants?
C. tertium
C. histolyticum
C. carnis
Quels Clostridium sont immobiles?
C. ramosum
C. innocum
C. perfringens
Quels clostridium ont une zone de double hémolyse?
C. perfringens
C. noyvi
Quels Pseudomonas sont Oxydase - ?
P. oryzhabitans
P. luteola
Quelles bactéries sont H2S + au TSI ?
Citrobacter spp
Proteus vulgaris/mirabilis
Edwardsiella tarda
Salmonella enterica (typhi et paratyphi)
Quelles bactéries sont Oxydase + et poussent en présence de NaCl 6,5% ?
La liste est longue mais entre autre :
Vibrio vulnificus
Vibrio parahemolyticus
Vibrio algolyticus
Vibrio fluvialis
Quelle est la seule entérobactérie oxydase + ?
Plesiomonas shigelloides
À part les test phénotypiques, comment peut-on différencier un S. pneumo d’un S. viridans?
Le séquençage du gène rpoB ou tuf
MALDI-TOF et ARN16s incapables de les différencier
Quels Streptococcus sont CAMP + ?
S. agalactiae (gène cfd)
S. iniae
S. pseudoporcinus
S. porcinus
Quelles bactéries ont un CAMP inversé positif ? (2)
C. perfringens (phospholipase C)
Arcanobacterium haemolyticum
(parfois vu avec C. ulcerans et C. pseudotuberculosis aussi)
Quels sont les deux Enterococcus mobiles?
E. casseliflavus
E. gallinarum
** Aussi les 2 Enterococcus ayant une R intrinsèque à la Vanco (vanC)
Nommer 8 CGP, catalase - et anaérobie facultatif.
- Abiotrophia
- Granulicatella
- Gemella
- Leuconostoc
- Pediococcus
- Vagococcus
- Alliococcus
- Aerococcus
Quelles bactéries ont une forme d’épingle au Gram?
- Yersinia pestis (plus classique à la coloration Wright, Giemsa, Wayson)
- Burkholderia pseudomallei et mallei
- Vibrio parahemolyticus
- Haemophilus ducreyi
- Klebsiella granulomatis
Quels sont les groupes de Lancefield dans lesquels les Streptococcus groupe anginosus agglutinent.
Groupes A, C, F et G
Nommez 5 BGP aérobie qui peuvent être catalase négatif.
ELGA(R)
Erysipelothrix rhusiopathiae
Lactobacillus spp.
Gardnerella spp.
Arcanobacterium spp.
Rothia (peut être catalase + aussi)
Truepurella aussi
BGP aérobie qui sont CAMP positif.
- Listeria monocytogenes
- Rhodococcus equi
- Turicella otitidis
5 tests phénotypiques qui peuvent aider à l’identification de B.anthracis :
- Mobilité (non mobile)
- Capsule (encre de chine)
- Test de lyse par bactériophage Gamma
- PCR visant plasmide pOX1 et pOX2
- Test de ténacité + pour B. anthracis
Which species of Vibrio will appear yellow on TCBS?
- V.cholera
- V. alginolyticus
- V. fluvialis
(a few others but these are the important ones)
What is the test that can differentiate Vibrio from Aeromonas?
String test : In this test, organisms are emulsified in 0.5% sodium deoxycholate, which lyses Vibrio cells, but not those of Aeromonas spp.
What are the 2 species of Vibrio that do not require salt for growth?
- V.cholera
- V.mimicus
What are the factors needed by Granulicatella and Abiotrophia for growth?
Cysteine or pyridoxal
Name 2 species of Lactobacillus intrinsically resistant to vancomycin
L. casei
L. rhamnosus
Tests pour identification de S.maltophila.
- Oxydase
- Mobilité
- Maltose
- Indole
- DNAse
- Oxydase - (20% sont +)
- Mobilité +
- Maltose +
- Indole -
- DNAse +
Quel espèce de Burkholderia est non motile?
B.mallei
Quels sont les tests qui permettent de différencier les BGP partiellement acid fast / embranchés?
- Partially acid fast or not
- Apparence sur tap water agar (hyphen, branching)
- Lyzozyme resistance
- Urea hydrolysis
Name 2 aerobic GPB that can have extensive branching.
- Nocardia
- Streptomyces
Less extensive :
- Gordonia
Donner des tests, ou caractéristiques de croissance, qui permettent de différencier le N. gono du N. meningitidis.
- Superoxol = positif pour le N. gono
- Croissance faible/nulle du N. gono sur une GS, vs croissance normale du N. meningitidis
- Croissance possible du N. méningitidis sur MH au sang de mouton
- Méningo sur gélose choco: colonies grises avec décoloration verdâtre de la gélose (vs colonies plus blanches sans décoloration pour gono)
- Gono : R au colistin
- Méningocoque maltose +
Nommez les 5 Staphylococcus ayant un clumping factor positif
S. aureus
S. lugdunensis
S. schleiferi
S. sciuri
S. intermedius
Labo sentinel : Décrire les réactions attendues pour la motilité, l’hémolyse, et la sensibilité à la PNC pour :
- B. anthracis
- B. cereus
- B. cereus biovar anthracis
- Il n’y a pas de cas décrits d’infection chez les humains avec B.cereus biovar anthracis
Haemophilus can be confused with Brucella. What are 2 easy tests that can differentiate both?
- Growth on blood agar (oui pour Brucella, non pour Haemophilus influenzae)
- Satellite test with S.aureus streak
Germe?
Yersinia pestis
Quel supplément requiert F.tularensis pour pousser?
Cystéine
Nommer un Staphylococcus qui n’est pas différenciable du S. aureus par ARN16S
S. aureus sous espèce anaerobius
S.aureus, S.schleiferi and S.lugdunensis are slide coagulase positive. What rapid test can be done to identify S.aureus from the 2 others?
PYR. Will be negative (or weak positive) for S.aureus and strong positive for the other 2.
Apart from S.agalactiae, what other 2 Streptococcus species can agglutinate Lancefield B group?
S.pseudoporcinus (can also be B-hemol, but it PYR+)
S.halichoeri (usually non B-hemol, is PYR +)
M35 : What is the expected reaction for N.gonorrhea for
1. γ-glutamyl-aminopeptidase
2. ß-galactosidase
- Negative
- Negative