Photodynamic therapy

BACKGROUND: We aimed to evaluate the efficacy of alternative therapies rather than the current antifungal conventional therapy and with assessing the hypothesis of photoactivation of citrus essential oil, fluconazole and Indocyanine green to treat two common mucocutaneous fungal infections.

METHODS: Suspensions of Candida albicans and Tricophyton rubrum containing 10(6)cells/ml was prepared. Equal samples were treated with infrared (IR) laser irradiation (810 nm, 55 J/cm(2)) in the presence of Indocyanine green (Emundo, 1 mg/ml) (IRLE), photoactivated Citrus aurantifolia essential oil (EO) with sequential exposure to natural and tungsten lights (CE), control non-activated essential oil (CC), laser alone (IRL), indocyanine green alone (E) and neither of treatments as the control group (C). Additional fluconazole (FL, 25.6μg/ml) and IR activated fluconazole (IRLFL) groups were designed for T. rubrum fungi. Inoculums were serially diluted to 10(-2) and 10(-4) and streaked on Sabouraud dextrose agar plates. Final outcomes were assessed as the percent of reduction.

RESULTS: Cell reduction rates (%) in C. albicans groups were 99.99 (CE), 91.67 (IRLE), 86.67 (CC), 72.37 (E) and 67.27 (RL). Whereas, a 99.99 (CE), 89.99 (CC), 74.5 (IRLE), 64.5 (E), 38.5 (IRLF), 37.5 (RL), and 31 (FL) percent eradication was achieved in T. rubrum groups.

CONCLUSION: Photoactivation of Citrus EO increased the killing capability by 10-13%. A modest 7.5% augmented effect was observed with IR activation of Fluconazole. Both Citrus EO and photothermal-photodynamic therapy with ICG and IR diode laser exhibited remarkable lethal effect on fungal cells. Candida viable cells are more susceptible to laser only and ICG only treatments than Tricophyton cells.