Effects of Photodynamic Therapy on the Growth and Antifungal Susceptibility of Scedosporium and Lomentospora spp.

Scedosporium and Lomentospora species are the second most frequent colonizing, allergenic, or invasive fungal pathogens in patients with cystic fibrosis, and are responsible for infections varying from cutaneous and subcutaneous tissue infections caused by traumatic inoculation to severe systemic diseases in immunocompromised patients. The clinical relevance of fungal airway colonization for individual patients harboring Scedosporium and Lomentospora species is still an underestimated issue. The high resistance of Scedosporium and Lomentospora species to antifungal drugs has highlighted the need for alternative treatment modalities, and antimicrobial photodynamic therapy may be one such alternative. In this study, methylene blue was applied as a photosensitizing agent to 6 type strains of Scedosporium and Lomentospora species, and we irradiated the strains using a light-emitting diode (635 ± 10 nm, 12 J/cm2). We evaluated the effects of photodynamic therapy on strain growth and on the in vitro susceptibility of the strains to itraconazole, voriconazole, posaconazole, and amphotericin B. A colony-forming unit reduction of up to 5.2 log10 was achieved. Minimal inhibitory concentration ranges also decreased significantly with photoinactivation. Photodynamic therapy improved both the inactivation rates and the antifungal susceptibility profile of all fungal isolates tested.

Synergistic effects of tetrandrine on the antifungal activity of topical ketoconazole cream in the treatment of dermatophytoses: a clinical trial.

OBJECTIVE: To evaluate the synergistic effects of tetrandrine (TET) on the antifungal activity of topical ketoconazole (KCZ) in the treatment of dermatophytoses. METHODS: The minimum inhibitory concentrations (MICs) for KCZ and combined KCZ and TET were compared in vitro. A randomized, double-blind trial was conducted among 97 patients with dermatophytoses who were assigned to 3 groups and received: treatment with combination of 2% KZC and 2% TET cream (KCZ + TET group), or only 2% KZC cream (KCZ group), or 2% TET cream (TET group). Patients with tinea corporis and/or tinea cruris were treated for 2 weeks, separately. The patients with tinea pedis and/or tinea manuum were treated for 4 weeks. RESULTS: Compared with KZC alone, combined use of KZC and TET showed lower MICs against clinical isolates of dermatophytes (P<0.05 for all). In the patients with tinea corporis and/or tinea cruris, the rates of overall cure (clinical cure plus mycologic clearance) were 81.25% vs. 33.33% for combined treatment and KZC monotherapy, respectively, after 4 weeks. All clinical indices were significantly different between the combination therapy and only KCZ therapy groups (P<0.05). Among the patients with tinea pedis and/or tinea manuum after 4 weeks treatment, the overall cure rates in the KCZ + TET group and KCZ group were 75.00% vs. 40.00%, respectively. In the KCZ + TET group, all the clinical indices were significantly better than those in the KCZ group and TET group (P<0.05). The rates of overall efficacy in the TET group were all zero. No local skin redness or itching was observed during TET treatment. No clinically significant changes were found in post-treatment routine blood, urine, or stool tests, ECG, or tests for liver and kidney function; no serious adverse events occurred. CONCLUSION: TET synergistically enhanced the clinical efficacy of topical KZC cream in the treatment of dermatophytoses.