Microscopy Flashcards
A differential staining technique based on bacterial cell wall structure
Gram stain
A differential staining technique based on bacterial cell wall structure Classifies bacteria as:
GRAM-POSITIVE
GRAM-NEGATIVE
Primary stain of Gram stain
Crystal violet
Mordant of Gram stain
Grams Iodine
Decolorizer of Gram stain
Acetone-alcohol
Counter stain of gram stain
Safranin
Fungal elements appear as
Gram-positive or Gram-variable
Examine for —- to confirm if yeast cells and not bacteria or
artifact
budding cells
India ink is used for
Cerebrospinal fluid
stain is the background, yeast cells remain unstained
Negative stain (india ink)
India ink results
Findings:
Encapsulated yeast cells - present
Positive for encapsulated yeast cell/s
India ink results
Findings:
Encapsulated yeast cells - absent
No encapsulated yeast cell/s seen
Direct examination of specimen for rapid detection of fungal elements
KOH Wet Mount
Direct examination of specimen by using a
CLEARING AGENT (KOH Potassium Hydroxide)
How many percent of KOH utilized for skin scrapings and other specimens
10% KOH (Potassium Hydroxide)
How many percent of KOH utilized for tissue, nails, hair
20% KOH (Potassium Hydroxide)
is a compound that stains the fungal cell wall, can be helpful in revealing fungal elements in wet mounts when examined under a fluorescence microscope.
Calcofluor White
Not to use KOH reagent if is
old or already crystallized
KOH Wet Mount - Results
Findings
Positive of Yeast cells and Hyphae
Reporting
Positive for yeast cells and hyphae
KOH Wet Mount - Results
Findings:
Present of Yeast Cells, absent of hyphae
Positive for yeast cells
KOH Wet Mount - Results
Findings:
Absent of Yeast Cells, present of hyphae
Reporting:
Positive for hyphae
KOH Wet Mount - Results
Findings:
Absent of Yeast Cells, absent of hyphae
Reporting:
No fungal elements seen
The polysaccharide capsule of Cryptococcus spp. exclude the ink particles giving a
—- around the organism
in a semi-opaque background
“clear halo”
