Lab Dx Mycology Flashcards
It is recommended that specimens should be stored under refrigeration at what temperature?
4degreesC
All specimens should be collected _______ and placed in sterile containers.
aseptically
This should be stored at 30-37degreesC
Blood and CSF
This should be stored at 15-30degreesC
Dermatologic specimens
Collection notes for BLOOD
Wright’s or Giemsa stain bottles
Isolation media for BLOOD
Sodium polyethanol sulfonate (SPS)
Collection notes for BONE MARROW
Heparin as anticoagulant and collect 0.5 ml of marrow
Isolation media for BONE MARROW
BHI broth, SDA
Collection notes for CSF
> 2ml: centrifugation
<2ml: uncentrifuged specimen
Isolation media for CSF
SDA, BHI with blood
Collection notes for HAIR
Hairs that fluoresce or are broken and scaly
Isolation media for HAIR
SDA, SDA-CC
Collection notes for NAILS
Scrape dissolved or hyperkeratotic areas
Isolation media for NAILS
SDA, SDA-CC
Collection notes for SKIN
Scrape outer edge of ring in ringworm infections
Isolation media for SKIN
SDA, SDA-CC, SDA with oil for Malassezia
Collection notes for MUCOCUTANEOUS
Scraping plaque with tongue depressor if Candida is suspected
Isolation media for MUCOCUTANEOUS
SDA, SDA-CC
Collection notes for SUBCU TISSUE, LESIONS AND ABSCESSES
Biopsy or needle aspiration and examine presence of granules
Isolation media for SUBCU TISSUE, LESIONS AND ABSCESSES
SDA, SDA-CC, anaerobic BHI with blood
Collection notes for SPUTUM, BRONCHIAL WASHINGS AND TRANSTRACHEAL ASPIRATES
Early morning sputum for 3 consecutive days
Isolation media for SPUTUM, BRONCHIAL WASHINGS AND TRANSTRACHEAL ASPIRATES
SDA, BHI with blood and CC, anaerobic BHI with blood
Collection notes for THROAT
2 sterile swabs
Isolation media for THROAT
SDA, SDA-CC
Collection notes for URINE
Midstream clean catch and detect fungal elements
Isolation media for URINE
SDA, SDA-CC
Collection notes for VAGINAL, CERVICAL
2 swabs examine with KOH
Isolation media for VAGINAL, CERVICAL
SDA, SDA-CC
Source of culture media
Nitrogen and carbon
What does fungi prefer for its growth?
Moisture and increased humidity
How many weeks should a culture be incubated?
2-4 weeks
Yeasts grow within _______ while H. capsulatum require _________ weeks to grow
24 to 72 hours… 10-12
Give the four Primary Isolation Media
SDA, BHI, DTM, Mycosel/Mycobiotic Agar
General isolation medium and it contains peptone and glucose
Sabouraud’s Dextrose Agar (SDA)
Primary recovery of saprobic and pathogenic fungi
SDA
Isolation of saprophytic and pathogenic fungi from sterile sites especially SYSTEMIC MYCOSES
BHI
Useful for pathogenic fungi exclusive for dermatophytes
BHI
For the recovery of fungi from BLOOD and BONE MARROW
BHI Biphasic Culture Bottles
Isolation of dermatophytes from hair, skin and nail specimens
DTM
Indicator that it has changed to alkaline pH
Yellow to red
Inhibitory agents: cycloheximide and chloramphenicol. This is similar to DTM
Mycosel/Mycobiotic Agar
This is a differential culture media wherein it shows stimulation of conidiation and chlamydospore production in Candida spp
Cornmeal Agar with Tween 80
Useful for spp ID of Candida
Cornmeal Agar with Tween 80
Cornmeal agar: numerous chlamydospores with flight clusters of blastoconidia
C. albicans
Cornmeal agar: fewer blastoconidia and no chlamydospores present
C. tropicalis
Cornmeal agar: colonies appear as “spiders”
C. parasilopsis
Cornmeal agar: elongated blastoconidia in a “log in a stream” arrangement
C. pseudotropicalis
Differential culture media for the isolation of C. neoformans
Birdseed/Niger seed Agar
This production breaks down the medium resulting to melanin forming black brown colonies
Phenol Oxidase
Differential culture media useful in slide cultures
Potato Dextrose Agar
Differential culture media which demonstrates pigment production of T. rubrum
PDA
Differential culture media for the detection of Urease producrion by C. neoformans
Urea Agar
Differenti culture media which differentiates T. rubrum from T. mentagrophytes
Urea agar
They can grow as white patches with glossy surface
Candida
They often appear whitish grey with fuzzy edges
Molds
Used in screening for keratinized tissue
KOH mount
Most accurate method to preserve and observe fungal microstructure
Slide culture
Slide culture should not be performed on ______, _______, and ________.
Coccidioides, Histoplasma, Blastomyces
To identify the capsule of C. neoformans
India ink
Used to visualize microscopic fungal morphology by imparting a blue color to the cell walls
LPCB
A brightening agent can bind to the chitin in the fungal cell wall providing contrast when examined under fluorescence xscope
Calcofluor white
Used for the detection of Intracellular Histoplasma capsulatum; C. neoformans also stains quite well in this mtd
Giemsa or Wright’s stain
Used to screen fungi in histologic spx; fungi is outlined black against pale blue background
Methenamine-Silver Nitrate Stain
Stains hyphae of molds and some yeasts
PAS
Hydrolyzes CHO of cell walls of the org to form aldehydes and then react w fuchsin dye to form pink-purple complex
Periodic Acid
Differential test specific for C. albicans
Germ tube test
Differential test for specie ID of some yeasts; INOSITOL:C. Neoformans vs Rhodotorula
CHO Assimilation Test for Yeast
Differential test specific for Cryptococcus spp
Rapid Urease Test