PPT 9-12

• A direct microscopic examination should be done of all specimens received for culture of fungi.
• Wet Preparations are microscopic examinations done before culture.
• Tease Mounts are microscopic examinations done from a mold colony after culture.
• Cellophane Tape Mount is an alternative to Tease Mount.
• Growth rate is a factor in the identification of fungi, with rapid growers taking less than 5 days, intermediate growers taking 6 to 10 days, and slow growers taking 11 or more days.
• Textures of fungi can be yeastlike, cottony, or granular.
• Topographies of fungi can be flat, cerebriform, or folded.
• The germ tube test is the most generally accepted and economical method used in the clinical laboratory for the identification of yeasts.
• Yeasts recovered from clinical specimens are C. albicans, and the germ-tube test usually provides a sufficient identification of this organism within 3 hours.
• Candida dubliniensis is a TRUE GERM TUBE.
• Candida tropicalis is a PSEUDO-GERM TUBE.
• A 10% to 20% solution of KOH is useful for detecting fungal elements embedded within skin, hair, nails, and tissue.
• Hair specimens should be collected using sterile forceps and placed directly into a sterile Petri dish.
• Skin specimens should be collected from a dermatophyte "ring" or scaling skin, and the skin must be cleaned with 70% alcohol before collection.
• Yeastlike is a bacteria like colonies texture
• Cottony a wooly texture
• Granular a powdery texture
• Flat- most common topography
• Cerebriform- colonies look loke a brain
• Folded- with random folds rather than grooves
• Germ tube has no constriction
• Pseudohyphae has constriction
• Nail specimens may be submitted as scrapings or or cuttings
• Nails are cleaned with 70% isopropyl alcohol befire the surface is scraped
• Deeper scrapings are necessary to prepare a KOH preparation and inoculate media
• Sterile scissors are used to cut complete nails into small thin strips, which are used to incoculate media