, Volume 171, Issue 4, pp 235–250

A Review of the Ultrastructural Features of Superficial Candidiasis



Commensal yeast Candida causes opportunistic infections ranging from superficial lesions to disseminated mycoses in compromised patients. Superficial candidiasis, the commonest form of candidal infections, primarily affects the mucosa and the skin where Candida lives as a commensal. Conversion of candidal commensalism into opportunism at the fungal–epithelial interface is still ill-defined. Nevertheless, fungal virulence mechanisms such as adhesion to epithelia, morphogenesis, production of secretory hydrolytic enzymes, and phenotypic switching are thought to contribute in the process of pathogenesis. On the other hand, host responses in terms of immunity and local epithelial responses are actively involved in resisting the fungal challenge at the advancing front of the infection. Ultrastructural investigations using electron microscopy along with immunohistochemistry, cytochemistry, etc. have helped better viewing of Candida–host interactions. Thus, studies on the ultrastructure of superficial candidiasis have revealed a number of fungal behaviors and associated host responses such as adhesion, morphogenesis (hyphae and appresoria formation), thigmotropism, production and distribution of extracellular enzymes, phagocytosis, and epithelial changes. The purpose of this review is to sum up most of the ultrastructural findings of Candida–host interactions and to delineate the important pathological processes underlying superficial candidiasis.


Candidiasis Candida species Cytochemistry Electron microscopy Histopathology Immunohistochemistry 



Chick chorio-allantoic membrane


Human immunodeficiency virus


Intracytoplasmic membrane structures


Intracytoplasmic membrane tubules




Phospholipase B


Polymorphoneuclear leukocytes


Secretory aspartyl proteinase


Scanning electron microscope


Transmission electron microscope


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© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  1. 1.Division of Microbiology, Department of Oral Medicine and Periodontology, Faculty of Dental SciencesUniversity of PeradeniyaPeradeniyaSri Lanka

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