1. Mycology – Introduction
Student Lab
Division of Medical Technology
Carol Larson MSEd, MT(ASCP)

2. Mycoses
Superficial
Subcutaneous
Systemic
Opportunistic

3. Characteristics of fungi
Eukaryotic
Growth requirements
Forms
Mold
Yeast

4. Hyphae
Septate
Aseptate

5. Hyphae
Hyaline
Dematiaceous

6. Mycelium Mass of branching intertwined hyphae Vegetative Aerial
Fertile

7. Vegetative types Favic chandeliers Nodular organs Racquet hyphae
Spiral hyphae

8. Reproduction Identify fungi by: Morphology of reproductive structures
Spores from vegetative mycelium or aerial fruiting bodies

9. Asexual Reproduction
Conidia
Conidiophore
Arthroconidia

10. Asexual Reproduction Blastoconidia Pseudohyphae Chlamydoconidia
Chlamydospores

11. Asexual Reproduction
Macroconidia
Microconidia
Phialoconidia
Phialide

12. Asexual Reproduction Annelloconidia Annellide Sporangiospores
Sporangium
Sporangiophore

13. Sexual Reproduction Perfect Fungi – has a sexual stage
Fungi Imperfecti – no know sexual stage
Spores

14. Sexual Reproduction
Ascospores
Ascus
Ascocarp
Basidiospores
Zygospores

15. In review … Mycoses – fungal diseases Characteristics of fungi
Growth requirements
Forms (mold, yeast)
Structures
Reproduction
Asexual
Sexual

16. Fungal Culture Process
Specimen collection and transportation
Direct examination of specimen
Selection and inoculation of media
Evaluation of fungal growth
Serological testing
Antifungal susceptibility testing

17. Specimen Collection Specimen types
Collect from area most likely infected
Use sterile technique
Keep specimen moist
Label container properly
Transport right away
Process right away

18. Direct Examination Provides preliminary report
Guides MD in treatment of patient
Observe yeast phase of dimorphic
Gives clues to id causative agent
Inoculate special media
May require more than one direct examination method

19. Direct Examination Saline wet mount Lactophenol cotton blue wet mount
10% KOH preparation
Gram stain
Acid fast stain
India ink stain

20. Direct Examination Calcofluor white stain Wright’s stain
Gomori Methenamine Silver stain
Periodic Acid Schiff stain

21. Specimen Processing Safety Tube media preferred over plate media
Work in safety hood
Wear gloves and lab coat
Autoclave specimens and media
Disinfect work area daily

22. Specimen Processing Primary isolation media
Goal: isolate potential pathogens
Use non-selective and selective media
Proper ingredients
Incubation temperature
Incubation time
Incubation atmosphere

23. Non-selective Media Sabouraud dextrose agar
Brain heart infusion (BHI) with/without 5% blood and 1% glucose

24. Selective Media Mycosel agar Inhibitory mold agar
Dermatophyte test medium

25. Subculture / Identification Media
Neutral Sabouraud dextrose agar (Emmon’s)
Cornmeal-Tween 80 agar
Niger seed agar (Birdseed agar)
Tween 80 / Oxgall / caffeic acid agar
Potato dextrose agar

26. Examination of Culture Growth
Potential pathogens
Slow growers
Growth on Mycosel
Color: dull buff, brown, mousy gray
Dimorphic

27. Examination of Culture Growth
Growth rate
Rapid growers: 1-5 days
Intermediate growers: days
Slow growers: >10 days

28. Colony Morphology – Appearance
Rugose
Umbonate
Verrucose
Flat

29. Colony Morphology – Texture
Cottony
Glabrous
Granular
Velvety

30. Colony Morphology – Pigmentation
Surface
Reverse

31. Microscopic Morphology
Definitive means of identification
Evaluate:
Shape
Method of production
Arrangement of conidia/spores
Size and color of hyphae

32. Microscopic Techniques
Tease mount
Scotch tape preparation
Slide culture

33. Serological Diagnosis
Immunodiffusion
Complement fixation
EIA
Latex agglutination

34. Antifungal Susceptibility
Determine appropriateness
Standardization of testing
Methods
Predictability in vivo
Antifungal agents

35. In Summary … Specimen collection and transport
Specimen processing and culture
Direct examination of specimen
Examination of culture
Serological testing
Antifungal susceptibility