For additional information, particularly about fungal species mentioned in the subsequent text, also refer to the paperback, Medically Important Fungi: A Guide to Identification by Larone.
Superficial Infections

Cellular response of host usually absent - no pathology elicited by fungus

  1. Organism remote from living tissue (primarily in the stratum corneum - compact dead layer of skin).
  2. Infection is insignificant and ignored by bodies defenses.
Identification accomplished several ways
  1. Visual Inspection
  2. Wood's lamp - U.V. lamp to look for presence of fluorescence.
  3. Scraping off cells onto a slide and clearing tissue with 10% KOH and flaming the slide.  Look for fungal tissue (e.g., mycelial fragments, yeast cells, spores).  These slides are not permanent because the KOH causes cells to breakdown over time - too caustic!
  4. Stripping tape - Scotch tape is pulled of skin, mounted on a slide,  and stained with crystal violet, methylene blue, or iodine.
  5. Isolation and subculturing of fungus.



Fungal Growth in the Ear Canal

Fungal Growth in Culture (Aspergillus niger)


Scopulariopsis, (S. brevicaulis)





PIEDRA     White piedra (Trichosporon beigelii)

    Black piedra (Piedraia hortae or P. hortai - Refer to Figures 34-36 on page 53 in the textbook)

Identification Both types of piedra are easy to treat!




TINEA NIGRA          Treatment - readily treated, over several weeks


Internet Links for additional information