DESCRIPTIONS OF MEDICAL FUNGI

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Descriptions of Medical Fungi
Candida Berkhout
The genus Candida is characterised by globose to elongate yeast-like cells or
blastoconidia that reproduce by narrow-based multilateral budding. Pseudohyphae and
occasionally true hyphae may also be present. Colony pigmentation is usually absent.
Ballistoconidia are not formed. Arthroconidia may be formed, but not extensively.
Sexual reproduction is absent. Glucose may be fermented. Nitrate may be assimilated.
Starch-like compounds are not produced. The diazonium blue B reaction is negative.
The genus is highly polyphyletic, as it comprises mitosporic species that are devoid of
special distinguishing features (Lachance et al. 2011).
Recently, several taxonomic rearrangements have been made and many well-known
Candida species have been renamed and moved to other genera, notably Pichia
kudriavzevii (formerly Candida krusei), Meyerozyma guilliermondii (formerly Candida
guilliermondii), Clavispora lusitaniae (formerly Candida lusitaniae), Kluyveromyces
marxianus (formerly Candida kefyr) and Wickerhamomyces anomalus (formerly
Candida pelliculosa). C. glabrata and C. parapsilosis are now recognised as species
complexes (Tavanti 2005; Correia 2006; Alcoba-Florez 2005).
Several species may be aetiological agents, most commonly Candida albicans, followed
by C. parapsilosis, C. glabrata, C. tropicalis and Pichia kudriavzevii. Altogether, these
five species account for >95% of human infections. However a number of other species
may also be isolated. All are ubiquitous and occur naturally on humans.
a
b
10 μm
Candida albicans showing (a) typical cream-coloured, smooth surfaced, waxy
colonies and (b) narrow based budding spherical to ovoid blastoconidia.