Fungal Specimen Collection And Hand

Question 1

Sample Processing Time

Answer 1

Process samples within 2 hours from receipt.

Question 2

Refrigeration for Delayed Testing

Answer 2

Delay in testing of intravascular catheter tips, other medical devices (stents, surgical implants, replacement joints, etc.), lower respiratory tract or urine specimens -> Refrigerate at 4°C.

Question 3

Storage of Dermatologic Specimens

Answer 3

Dermatologic specimens (skin, hair, nails) are very sensitive to cold → Hold at room temperature (22-25°C).

Question 4

Incubation: Blood, Bone marrow, Tissue, Sterile fluids

Answer 4

30°C; TAT 21 days.

Question 5

Incubation: Hair, Skin, Nail scrapings

Answer 5

30°C; TAT 21 days.

Question 6

Incubation: Vaginal, Throat, Mouth samples

Answer 6

30°C; TAT 7 days.

Question 7

General purpose/Routine media for fungi

Answer 7

Sabouraud Dextrose Agar (SDA)

Question 8

Selective media for pathogenic fungi, inhibits saprophytic fungi (for clinically significant)

Answer 8

SDA with cycloheximide

Question 9

Primary recovery of saprobic and pathogenic fungi

Answer 9

Brain-Heart Infusion Agar (BHIA), Potato flake agar, Sabouraud dextrose with brain-heart infusion (SABHI) agar

Question 10

Primary recovery of pathogenic fungi not including dermatophytes (Antibiotics: chloramphenicol, cycloheximide, gentamicin)

Answer 10

Brain-Heart Infusion Agar (BHIA) with antibiotics, Yeast-extract phosphate agar with ammonia

Question 11

Enhances recovery and sporulation of Blastomyces and Histoplasma

Answer 11

Yeast extract phosphate

Question 12

Primary recovery of pathogenic, cycloheximide-sensitive fungi exclusive of dermatophytes

Answer 12

Inhibitory mold agar

Question 13

Primary recovery of dermatophytes; recommended as screening medium

Answer 13

Dermatophyte test medium

Question 14

Primary recovery of Dermatophytes (E.M.T species) = indicator phenol red

Answer 14

Mycosel/Mycobiotic agar

Question 15

Detection of ascospores in ascosporogenous yeasts (e.g., Saccharomyces spp.) = components of yeasts - compounds of yeasts.

Answer 15

Acetate Ascospore Agar

Question 16

Identification of Cryptococcus, Trichosporon, and Rhodotorula spp.; Separation of Trichophyton mentagrophytes from Trichophyton rubrum.

Answer 16

Christensen’s Urea Agar

Question 17

Differentiation of Candida spp. by chlamydospore production.

Answer 17

Cornmeal Agar with Tween 80 and Trypan Blue

Question 18

Differential identification of Aspergillus spp.

Answer 18

Czapek’s Agar / Czapek-Dox Agar

Question 19

Identification of Cryptococcus neoformans and Cryptococcus gattii (creatinine for enhanced melanization).

Answer 19

Niger Seed Agar (Birdseed Agar)

Question 20

Demonstration of conidia formation and the pigment production by Trichophyton rubrum; preparation of microslide cultures and sporulation of dermatophytes.

Answer 20

Potato Dextrose Agar

Question 21

Identification of yeasts by determining fermentation.

Answer 21

Yeast Fermentation Broth

Question 22

Identification of yeasts by determining carbohydrate assimilation.

Answer 22

Yeast Nitrogen-Base Agar

Question 23

Enhanced recovery of Malassezia furfur.

Answer 23

SDA with Olive/Mineral Oil

Question 24

For Trichophyton mentagrophytes.

Answer 24

Hair Baiting in Media

Question 25

Differentiates Microsporum canis (positive) from Microsporum audouinii (negative).

Answer 25

Rice Medium

Question 26

Purpose of Lactic Acid and Glycerol

Answer 26

Preservation of structure.