Light and electron microscopic findings in a model of human cutaneous candidosis based on reconstructed human epidermis following the topical application of different econazole formulations

The effects of two commercially available econazole formulations (econazole nitrate cream, econazole liposome gel) on uninfected reconstructed human e pidermis and on a model of human cutaneous candidosis were investigated. Th e morphological alterations of the reconstructed epidermis after infection and treatment were analysed with light and electron microscopy. The most im portant Candida albicans-specific alterations of the recently established i n vitro model of human cutaneous candidosis were scaling, hyperkeratosis, p arakeratosis, dyskeratosis and spongiosis, A single application of the crea m to the uninfected reconstructed epidermis caused more epidermal barrier d amage and irritative toxic effects than the liposome gel. Treatment of the modelled human cutaneous candidosis with the cream also resulted in increas ed toxic effects, e.g., enhancement of scaling with invasion of Candida alb icans blastospores into the stratum corneum and intracellular vacuoles. Aft er application of the liposomal preparation invasion of Candida albicans in the stratum corneum could not be detected and toxic effects were reduced. Some of the Candida albicans-specific alterations such as hyperkeratosis, f ocal thickening of the stratum corneum, dyskeratosis and parakeratosis were completely eliminated. The liposomal formulation increased slightly the mo rphological alterations of the blastospores. Remnants of the cream formulat ion could be detected only very rarely in the stratum corneum or the blasto spores. The liposomal preparation showed a strong affinity for the Candida albicans cells and the stratum corneum, Intact liposomes could even be obse rved in the intercellular spaces of the upper stratum corneum. As successfu l treatment depends on the ability to target the liposomal agent to the wan ted site of action, this might be useful for more effective treatment of cu taneous candidosis.