MLSCI340 Mycology

Question 1

Discuss collection and submission of specimens for fungal examination

Question 2

Discuss media used for isolation and/or ID of fungi

Question 3

Discuss clinical significance of organisms listed in lab

Question 5

List the dimorphic forms of fungi

Answer 5

Smooth, creamy OR fluffy, powdery

Question 6

Discuss respiratory specimen collection/ handling in mycology

Answer 6

• collected immediately in the morning
• cough deeply from lungs (NOT SALIVA) = THICK, not watery
• sputum must arrive in lab within 2 hours of collection

Question 7

What temp are respiratory mycology specimens stored if not immediately sent to lab ?

Answer 7

4°C in fridge

Question 8

Describe blood specimen collection/ handling in mycology ?

Answer 8

• 70% alcohol antiseptic
• 2 bottles (aerobic and *) at 2 sites
• If dimorphic, 10 mL in SPS or isolator tube = held RT for 4 weeks

SPS - Sodium polyanethole sulfonate

Question 9

Discuss tissue collection / handling in mycology

Answer 9

• sterile technique + gauze moistened w/ sterile saline

Question 10

Discuss CSF/ sterile body fluid collection/ handling in mycology

Answer 10

• 2 sterile 10 mL tubes (2nd tube is submitted to micro)
• Fungal culture includes cryptococcal Ag testing + calcofluor white stain
• India ink stain used to ID large capsules seen with Cryptococcus

Question 11

Discuss MSU collection/ handling in mycology

Answer 11

• first morning collection
• ensure proper disinfection to remove normal flora
• urine into toilet before and after collection
• grey top vacutainer is okay at RT; 4°C in fridge if >20 min

Question 12

Discuss hair specimen collection/ handling in mycology

Answer 12

• fungal collection kit (envelope, black paper)
• forcep >10 hair (uncut)
• clean scalp not required

Hx:
- anti-fungal therapy
- travel
- predisposing factors (animal contact, immunodeficiency)

Question 13

Discuss skin specimen collection/ handling in mycology

Answer 13

• fungal collection kit (envelope, black pepper)
• disinfect with 70% alcohol
• scrape with sterile scalpel

Hx:
- anti-fungal therapy
- travel
- predisposing factors (animal contact, immunodeficiency)

Question 14

Discuss nail specimen collection/ handling in mycology

Answer 14

• fungal collection kit (envelope, black paper)
• clean w/ 70% alcohol
• use scalpel to remove debris from under nail
  Hx:
• anti-fungal therapy
• travel
• predisposing factors (animal contact, immunodeficiency)

Question 15

SDA use and selective ingredients

Answer 15

Sabouraud Dextrose Agar

Use: ENRICHED; primary recovery of saprobes (including dermatophytes)

Ingredients: sabouraud dextrose + brain-heart infusion agar

Question 16

What is SDA with anti-microbials used for ?

Answer 16

Selective between different saprobes

Question 17

BHI Agar use and ingredients

Answer 17

Brain-Heart Infusion Agar

Use: primary recovery of saprobes (bacteria, yeast, fungi)
Ingredients: Brain-heart infusion, enzymatic digest of animal tissue, casein, dextrose, NaCl

Question 18

Why may BHI be used with anti-microbials?

Answer 18

It is a rich medium for saprobes

Question 19

WIP What is the difference between saprobes and dermatophytes ?