School of Molecular & Biomedical Science
THE UNIVERSITY OF ADELAIDE
AUSTRALIA 5005

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Australasian Mycology QAP.

This page will provides results and information regarding the Australasian Mycology QAP Program.

To access further information about the Microbiology QAP go to Microbiology QAP.

Reports may be downloaded as pdf files and you will need Adobe Acrobat Reader to view these files.

List of QAP fungi [download pdf file].

2004 QAP Report [download pdf file].

2003 QAP Report [download pdf file].

2002 QAP Report [download pdf file].

2001 QAP Report  [download pdf file].

2000 QAP Report [download pdf file].

1999 QAP Report [download pdf file].

1998 QAP Report [download pdf file].

Practical Identification of Dermatophytes [download pdf file].

Notice to Laboratories [issued 20/10/98].

Laboratories should take note that Terbinafine (Lamisil) will be re-listed on the PBS for the treatment of laboratory proven onychomycosis from 1 November, 1998. This will mean an increase in the number of nail specimens received for both direct microscopy and culture.

The key element for the diagnosis of onychomycosis are the collection of an adequate specimen and the correct processing and interpretation of both microscopy and culture results. Clinicians and laboratory staff alike often have a misconception that the diagnosis of onychomycosis is easy; well in theory it should be, but in practice its not. It is important to stress that only 50% of dystrophic nails have a fungal aetiology and this is why laboratory proof of a dermatophyte infection is required before a prescription for Terbinafine may be issued on the PBS.

Specimen collection:

For a laboratory diagnosis, clinicians should be aware of the need to generate an adequate amount of material for the laboratory to perform both microscopy and culture. Quantity is the most important thing. Unfortunately many specimens submitted to the laboratory are either of an inadequate amount or are not appropriate to make a definitive diagnosis. A variety of collection tools have been used in attempts to gain better specimens and these include dental/engraving drills, household drills, punch biopsy instruments, bone curettes, tweezers, scissor blades and blunt scalpel blades. I prefer to use an old scalpel, but old dental instruments known as a "plastic' and a "spoon excavator" are also extremely useful [ask for one on your next visit to the dentist]. Basically, any blunt instrument that allows you to scrape out the debris from under a nail will do the job. A set of nail clippers is also essential.

L to R, Bone curette, blunt old type scalpel, old dental tools known as
a "spoon excavator" and a "plastic", scissors, forceps and nail clippers.

Clean the nail with an alcowipe. This helps to lower the contamination rate from other saprophytic moulds and yeasts that my overgrow a dermatophyte. Using a blunt scalpel, dental instrument, tweezers, or scissor blade firmly scrape under the nail plate until the crumbling white degenerating portion is reached. Collect all keratin debris from beneath the free edge of the nail directly onto a black collection card. This makes it easier to see how much material you have collected. Nail clippers should also be used to clip the distal portion of the nail. Remember, the greater the amount of specimen, the greater the chance of obtaining a positive result from both direct microscopy and culture.

Black collection cards showing a poor specimen on the left and a
good specimen on the right. It's important to collect enough
material for both direct microscopy and culture.

Interpretation of laboratory results:

Laboratory managers also need to recognise that the current diagnostic methods are labour intensive and require special interpretative skills, especially when examining direct microscopic slides of clinical material and in the identification of fungal cultures. Routine turn around times for direct microscopy should be less than 24 hours, however culture may take several weeks.

1. Direct Microscopy: This provides vital information, often a presumptive diagnosis is possible, which is of particular importance if laboratory proof is required before treatment may commence. However, recognition of fungal elements in skin and nail specimens is a technique which requires considerable experience and expertise. Fungal elements within the specimen may be scanty in number, and thus be missed by the inexperienced, resulting in false negatives. The presence of hyaline, septate fungal hyphae, often forming arthroconidia should be considered significant and is presumptive of a dermatophyte infection. The presence of budding yeast cells and pseudohyphae is also significant and is presumptive of a Candida infection. Some non-dermatophytic fungi such as Scopulariopsis, Aspergillus, Fusarium and Hendersonula may also cause rare infections of the nail. However, with Scopulariopsis characteristic conidia are usually seen within the nail body and with Hendersonula the presence of thick walled, dematiaceous brown pigmented septate hyphae can be detected by direct microscopy.

2. Culture: The growth of any dermatophyte is a significant culture result. Table 1 gives the relative incidence of dermatophytes isolated from different sites; the principle causative agents of onychomycosis are T. rubrum and T. mentagrophytes var. interdigitale. Interpretation of other culture results in onychomycosis is often more problematic. Dystrophic nails also harbour a large flora of saprophytic fungi, yeasts and bacteria associated with a non-sterile site, therefore the isolation of a yeast or other mould without a supporting microscopic result is not significant. For example, the isolation of Candida albicans is not significant without seeing budding yeast cells and pseudohyphae in the direct microscopy. Contaminant fungi may be isolated from two-thirds of patients examined (Table 2), but successive sampling of the same nail will rarely demonstrate the same contaminant.

Table 1. Incidence of dermatophytes causing Tinea cruris, Tinea pedis and Onychomycosis.

Table 2. Incidence of contaminant moulds and yeasts from nail specimens [note Scopulariopsis and Candida are often isolated as contaminants from a non-sterile site].

For more information see "Dermatophytosis" under the Mycoses section and Descriptions of Fungi section for culture identification.

Fungal Jungle

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