The high efficacy of luliconazole against environmental and otomycosis Aspergillus flavus strains

Luliconazole is currently confirmed for the topical therapy of dermatophytosis. Moreover, it is found that luliconazole has in vitro activity against some molds and yeast species. The aim of the present study was to evaluate the efficacy of luliconazole in comparison to routine used antifungals on clinical and environmental isolates of Aspergillus flavus.

Thirty eight isolates of A. flavus (18 environmental and 20 clinical isolates) were detected based on morphological and microscopic features and also PCR-sequencing of β-tubulin ribosomal DNA gene. All the isolates were tested against luliconazole, voriconazole, amphotericin B and caspofungin. Minimum inhibitory concentration (MIC), MIC50, MIC90 and MIC Geometric (GM) were calculated using CLSI M38-A2 protocol for both environmental and clinical isolates.

Luliconazole with extremely low MIC range, 0.00049-0.00781 μg/mL and MICGM 0.00288 μg/mL showed very strong activity against both clinical and environmental A. flavus isolates. Moreover, voriconazole inhibited 100% of isolates at defined epidemiological cutoff values (ECV ≤ 2 µg/ml). 50% and 27.8% of clinical and environmental isolates of A. flavus, were resistant to caspofungin, respectively. Whereas, all the isolates were found to be resistant to amphotericin B.

The analysis of our data clearly indicated that luliconazole (with MICGM 0.00244 µg/ml for clinical and 0.00336 μg/ml for environmental isolates) had the highest in vitro activity against A. flavus strains.