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The in vivo efficacy of terbinafine was compared to lanoconazole and luliconazole in the topical treatment of dermatophytosis caused by Trichophyton mentagrophytes using a guinea pig model. Topical antifungal treatment commenced three days post-infection, and each agent was applied once daily for seven consecutive days. Upon completion of the treatment period, evaluations of clinical and mycological efficacies were performed, as was scanning electron microscopy (SEM) analyses. Data showed that while all tested antifungals demonstrated significant mycological efficacy in terms of eradicating the fungi over untreated control, terbinafine and luliconazole showed superior clinical efficacy compared to lanoconazole (P-values < 0.001 & 0.003, respectively). Terbinafine demonstrated the highest clinical percent efficacy. SEM analysis revealed hairs from terbinafine and lanoconazole-treated animals had near complete clearance of fungi, while samples from luliconazole-treated animals were covered with debris and few conidia. This study demonstrates that, in general, terbinafine possessed similar efficacy to lanoconazole and luliconazole in the treatment of dermatophytosis. Terbinafine tended to have superior clinical efficacy compared to the azoles tested, although this difference was not statistically significant against luliconazole. This apparent superiority may be due to the fungicidal activity of terbinafine compared to the fungistatic effect of the other two drugs.

Dermatomycoses are among the world's most common diseases and their incidence has increased over recent years, particularly in immunosuppressed patients. In previous studies, the saponin CAY-1 from cayenne pepper (Capsicum frutescens), has shown antifungal activities against Candida albicans and Aspergillus spp. We therefore studied the in vitro antifungal activity of CAY-1 against non-germinating conidia and hyphae of clinical isolates of the dermatophytes Trichophyton mentagrophytes, T. rubrum, T. tonsurans and Microsporum canis. We used a microdilution method to assess the growth inhibitory activities of CAY-1 against conidia (CLSI document M38-A) and a colorimetric procedure (XTT method) to investigate the metabolic inhibitory activity of CAY-1 against hyphae. The minimal inhibitory concentrations (complete visual growth inhibition) of CAY-1 against non-germinating conidia ranged from 10-20 microg/ml for all dermatophyte isolates included in this investigation. In addition, we found >90% inhibition of hyphal metabolic activity of these same isolates with 10-20 microg/ml of CAY-1. Results indicate that CAY-1 merits further investigation as a potential agent for the treatment of dermatomycoses.

Research on fungi that cause opportunistic infections has increased dramatically during the past few years, largely because these organisms cause significant morbidity and mortality. Most of this research has focused on defining the virulence factors produced by these pathogens, as well as developing methods for the diagnosis of fungal diseases. With regard to studies on the biology of Candida albicans, it is now possible to isolate genes, disrupt their expression, and observe the specific effects of gene disruption on virulence and growth of the organism. Moreover, growth and virulence of this pathogen is also being studied and the effect of environmental factors on gene expression investigated. This subject is especially important in view of the fact that C. albicans can colonize and invade a number of sites in the human body. Thus, its ability to grown in the oral and vaginal tracts, as well as in blood, requires the organism to adapt to a variety of environmental stresses. Here we present observations on the growth, morphogenesis and virulence of the opportunistic fungi C. albicans and Aspergillus fumigatus.