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→Diagnosis of Fungal Infection
===Diagnosis of Fungal Infection===
===Diagnosis of Fungal Infection===
The main method used to determine the species of mycological infection is by culture. Any culturing procedures should be carried out in a biohazard cabinet due to the zoonotic effect of spores aerosols.
The main method used to determine the species of mycological infection is by culture. Any culturing procedures should be carried out in a biohazard cabinet due to the zoonotic effect of spores aerosols. Clinical signs and history may be sufficient to make a presumptive diagnosis, particularly when considering dermatophytoses. Any specimens taken for laboratory analysis can include hair and skin scrapings, biopsy or post-mortem (if the disease is a systemic mycosis).
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Direct examination of wet preparations via light microscope represents another method for diagnosis. Species that can be detected via this method include ringworm arthrospores around infected hairs, ''Cryptococcus neoformans'' within cerebrospinal fluid and spores taken from a colony cultured previously. In some cases an adhesive tape technique can be used to produce a slide for microscopic examination. This is performed by placing adhesive tape on the superficial site of infection and removing material attached to the tape.
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Where it is appropriate to use a culturing technique, fungi are usually isolated on a Sabouraud dextrose agar (pH 5.5) which inhibits the growth of most bacteria. In order to differentiate fungal species that may be implicated in mycotic disease a number of features are observed and utilised. These include the presence of absence of septa (internal cell walls), either colourless or pigmented hyaline structures or specific hyphal structures. The colonial characteristics may also be observed including size, appearance, colour and elevation.
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Yeasts are mainly differentiated based on colonial appearance and the size and shape of individual cells. There are also some biochemical tests that can be used for differentiation including ELISA.