GPB - Coryne, Lacto, Bacillus Flashcards
s/ small curved gpb, test catalase negative - a cause of pharyngitis in young adults
Arcanobacterium haemolyticum
Which Bacillus is penicillin: S?
B. anthracis
Motility of B. anthracis vs Bacillus spp.?
B. anthracis = non-motile
Bacillus spp. = motile
Erysipelothrix TSI result?
A/A H2S+
TINS: black colony with brown halo
Urease: POS
Corynebacterium ulcerans
granulomatosis infantiseptica is one of the severe manifestations of ______ - ________ disease seen with in utero infection by Listeria
EARLY-ONSET
entry via penetrating eye injury leading to endophthalmitis
B. cereus
Elek plate test purpose
Confirmation that an isolate is toxigenic
Used in conjunction w/ PCR for toxigenicity testing
Toxin from organism + anti-toxin (from inoculated strip) diffuse towards each other, forming lines of precipitation
Organism that may be AH, catalase neg, TSI is A/A H2S (+)
Erysipelothrix rhusiopathiae
Listeria macroscopic and microscopic characteristics
- BH narrow-band (may be delayed)
- sm
- wh-gr
- trans
Small regular gpb
This Bacillus species is non-motile, NH and not resistant to penicillin
ANTHRACIS
dormant resting stage of Bacillus and Clostridium
ENDOSPORE
The 3 organisms that will grow as black colonies with a brown halo on TINS
- C. diptheriae
- C. ulcerans
- C. pseudotuberculosis
Clinical significance of B. cereus (3 things)
Food borne - emetic
Food borne - diarrheal
Ocular - endophthalmitis
Purpose of Loeffler’s serum slant
Enhance growth and morphology of C. diptheriae
may be added to artificial culture for the recovery of lipophilic organisms
TWEEN 80
Corynebacterium that is associated w/ UTIs
C. urealyticum
Skin test that used to be administered to determine immune status against diptheria using an intradermal injection of diptheria toxin
Schick test
TINS: black colony, no halo; urease POS
Corynebacterium urealyticum
Media made as needed to screen for C. diphtheriae
TINS
Due to short shelf life
Can have tox+ virulence factor
C. diptheriae
C. ulcerans
Bacillus undergoes _______ in adverse conditions such as heat, drying and nutritional deprivation
SPORULATION
Corynebacterium atmospheric requirements?
Facultative ANO2, some obligate aerobes
Phosphate energy storage granules (Volutin granules, Babes-Ernst granules)
Metachromatic granules
Term for the use of 4 degree incubation to select for Listeria from a heavily mixed specimen
COLD ENRICHMENT
3 Corynebacteria biotypes
Gravis
Intermedius
Mitis
Abbrev. for a nutritionally-rich fermentation detection media that supports small pH changes (weak acid production)
CTA
Often isolated in combination w/ S. aureus and S. pyogenes
Cutaneous diphtheria
Some species of Corynebacterium will grow poorly or not at all on CHOC b/c they are __________
Lipophilic (need Tween 80 as supplement)
Corynebacterium catalase result?
Positive
one of two forms of food borne disease caused by Bacillus cereus; short incubation, often associated with infant formula and fried rice, leading to vomiting and cramping
EMETIC
toxin that retains its antigenicity but not its virulence (used in immunization)
TOXOID
Media containing beef serum, egg, dextrose
Loeffler’s serum slant
Hemolysis of B. anthracis vs Bacillus spp.?
B. anthracis = NH
Bacillus spp. = BH
Role that immunization status and low socioeconomic status plays in maintaining a reservoir of C. diptheriae
Humans are only reservoir
Lower socioeconomic status = overcrowding in slum area, poor access to health care = easily spread
Biotype of C. diphtheriae causing the most severe disease
Gravis
Can often be a lab contaminant
Bacillus
What causes suffocation in diptheria infection?
Pseudomembrane (necrotic tissue, immune cells, C. dipth)
Lactobacillus:
- Atmospheric = ?
- Catalase = ?
- Normal flora sites = ?
- Atmospheric = microaerobic
- Catalase = NEG
- Normal flora sites = vaginal flora, mouth
2 words: one of the distinctive macroscopic morphologies often seen with B. anthracis
MEDUSA HEAD
L. monocytogenes - definitive ID is confirmed with which test?
Hippurate test
B. anthracis s/ ?
gpb large ch boxcars
May have central to subterminal spores that don’t swell cell
Most have capsule
Describes motility in a room temp SIM for Listeria
Umbrella motility
primarily an occupational hazard e.g. vets, the main pathogen in this genus, __________ , is E. rhusiopathiae, a NH ppt (24h) s/gpb (filaments) testing catalase neg
ERYSIPELOTHRIX
Immediate treatment of presumptive diptheria infection?
Diptheria anti-toxin
Why is Listeria a facultative intracellular parasite?
- Can survive within monocytes
- Invades and multiplies in macrophages
Resemble viridans streptococci on BAP, but s/gpb slender or spiral or Cs
Catalase NEG
Lactobacilli
Presumptive ID of C. diphtheriae?
- Halo on Tinsdale
- Coryneform in colony smear
- Urease NEG
Corynebacterium that is very ABX resistant
C. jeikeium
Least fatal disease form associated with B. anthracis, even if untreated
Cutaneous
C. ulcerans on BAP (hemolysis)?
Weak BH, otherwise similar to C. diptheriae
Active immunization against three pathogens including, C. diphtheriae
DTAP vaccine
2 media useful in identification of Corynebacteria?
- Tinsdale
- Cystine Tellurite Blood Agar (CTBA) = selective and differential for it
on this plate test, lines of identity confirm a toxigenic strain of C. diphtheriae
ELEK
Corynebacterium that is multi-resistant to most antibiotics, but vancomycin: S
C. jeikeium
Term used for Corynebacterium species that are typically considered as commensals
DIPHTHEROIDS
Process used to sterilize Loeffler’s serum slant?
Coagulation-sterilization or inspissation or fractional sterilization
A positive in this test moves an isolate presumptively ID’d as Listeria monocytogenes by rapid ID from blood, CSF or prodcuts of conception to a definitive ID
Hippurate
hippurate POS
- Streptococcus agalactiae
- Listeria monocytogenes
Media used to biotype Corynebacteria
Cystine-Tellurite Blood agar (CTBA)
C. diptheriae
Cystinase = ?
Urease = ?
Cystinase POS (halo on TINS) Urease NEG
AH, ppt, s/long slender gpb
Catalase NEG
Lactobacilli
Describes the motility of Listeria at room temp in a HANGING DROP test
Tumbling motility
Corynebacterium species that is never considered normal flora
C. diphtheriae
Erysipelothrix disease
Localized cellulitis (occupational hazard due to contact w/ infected animals)
Typical diptheroids BAP morphology
NH, wh, dry/waxy/crumbly (friable), very op
Looks like dry wax
Cause of alkaline encrusted cystitis
C. urealyticum
IMMEDIATE treatment for a patient presumptively diagnosed with diphtheria
Diphtheria anti-toxin
s/ gpb small regular
Catalase WEAK POS
Listeria monocytogenes