Mycology Flashcards
Heterotrophs
Digest complex organic material (plant/animal) food internally
Heterotrophs may be what?
Parasitic or Saprophytic
Parasitic
Cause harm to the plant/animal host it is using for food
Saprophytic
Feed on dead/dying material
Where may you see saprophytic fungi?
Fallen trees
Yeast
Single-celled and reproduces by budding
Hyphae
Multicellular fungal organisms
Microscopic
Mycelium
Large branched webbings
Composed of hyphae
What are the supplies needed for collection & examination of fungal samples
- Forceps
- Swabs
- Lactophenol cotton blue
- Potassium hydroxide solution
- Culture media (DTM and/or Sabouraud agar)
Sabouraud Dextrose
Commonly found in most clinics
Does not contain an indicator
What stain confirms identity of fungal organisms?
Lactophenol cotton blue
What are the common fungal species?
Microsporum canis
Microsporum gypseum
Trichophyton mentagrophytes
Microsporum canis
Spores look like canoes and are pointed at the end
Microsporum gypsum
Similar to Microsporum canis but is more rounded does nit have the point at the end
Trichophyton mentagrophytes
Large and small spores
What percentage of cases with Microsporum canis show evidence of fluorescence?
50%
How long should a Woods lamp be warmed up for?
5 mins
What are the 3 ways to test for Dermatophyte testing?
Wood’s lamp
Dermatophyte test Medium
Rapid sporulation medium
Wood’s lamp
Infected hairs will glow in a dark room using fluorescence light
Dermatophyte Test Medium (DTM)
Culture media will turn in red in the presence of most dermatophytes
Rapid Sporulation medium (RSM)/Enhanced sporulation medium (ESM)
Culture media will turn teal in the presence of most dermatophytes
What color does a positive result for DTM yield?
Red
If the color change occurs is that 100% positive?
No. Confirm with microscopic examination
What agar types are used for non-dermatophytes typically?
Bismuth-Glucose-Glycine Yeast (Biggy)
Blood agar
Sabouraud dextrose agar
How do you do prepare a slide for microscopic evaluation of fungi?
Collect mycelium from the media with sticky side of clear cellophane tape
What stain do you place on the slide for microscopic evaluation?
Lactophenol cotton blue
How do you do evaluate fungus microscopically?
After placing the lactophenol cotton blue onto the slide, place the tape onto the stain and examine on 10x and 40x
