COLONIAL CHARACTERISTICS Flashcards
Age:
young or maturity
Rate of Growth:
Rapid Growers
Intermediate Growers
Slow Growers
Matures in less than 5 days
Rapid Growers
Saprobes: uses organic matter but doesn’t harm the host
Rapid Growers
Examples: Aspergillus and Ganoderma
Rapid Growers
6-10 days
Intermediate Growers
Dermatophytes and most opportunistic fungi
Intermediate Growers
Examples: Candida, Microsporum, Trichophyton
Intermediate Growers
11 days or more
Slow Growers
Systemic and subcutaneous fungi
Slow Growers
Example: Blastomyces, Coccidioides, Histoplasma
Slow Growers
both the obverse (front) and reverse (back)
PIGMENT
most are dematiaceous (olive green) - causes an infection in both
immunosuppressed and immunocompetent individuals
PIGMENT
how colonies look
TEXTURE
leathery/ waxy
Glabrous
with little mycelia
Glabrous
short aerial hyphae
Velvety/Suede
bacteria-like in appearance
Yeast-like
(coagulase negative Staphylococcus)
Yeast-like
no aerial mycelium
Yeast-like
wooly, floccose
Cottony
long aerial hyphae
Cottony
Powdery
Granular
fungi that conidiate heavily
Granular
colony surface arrangement
TOPOGRAPHY
“lay of the land”
TOPOGRAPHY
o with radial grooves from center to the rim
Rugose
o like a bicycle wheel
Rugose
o parallel at right angles
Folded
o volcano-like
Crateriform
o wart-like
Verrucose
o rough knobs at the surface
Verrucose
o with elaborate folds and convolutions
Cerebriform
M. MACROSCOPIC EXAMINATION
NOTE FOR:
Caseous material
Purulent exudate
Necrotic material
Granules
Punch biopsies
Layers of skin that are broken vertically (fissures)
CLINICAL SIGNIFICANCE
Provide an immediate presumptive diagnosis
Aid in the selection of appropriate culture media
Aid in decision of what’s best inoculation technique to use
PREPARATION FOR MICROSCOPIC EXAMINATION
Mince or grind hard specimens
Centrifuge for 3-5 mins fluid specimens
Pulverize nail clippings
Volume for fluid specimens: 0.5 ml
Assemble a wet chamber for incubation
- distorts colonial morphology
TEASE MOUNT
- rapid method
TEASE MOUNT
- may cause widespread dispersion of conidia
CELLULOSE TAPE SWAB
- morphology is preserved
CELLULOSE TAPE SWAB
- cannot be preserved for long periods
CELLULOSE TAPE SWAB
- substitute for wet mount
CELLULOSE TAPE SWAB
- 95% ethanol
CELLULOSE TAPE SWAB
- Applicator stick and tape
(disadvantage: not sterile)
CELLULOSE TAPE SWAB
- needs tease-mount first
MICROSLIDE/AGAR BLOCK