Determination of susceptibility of onychomycosis agents isolated in Sakarya province to octenidine dihydrochloride and hypochlorous acid

INTRODUCTION AND AIM: In this study, it was aimed to examine the susceptibility of onychomycosis agents isolated in Sakarya province to Octenidine dihydrochloride and Hypochlorous Acid by agar dilution, tube dilution and flow cytometry. MATERIALS AND METHODS: In the study, dermatophytes (Trichophyton, Microsporum, Candida etc.), which are the causative agents of onychomycosis in the culture collection, and Aspergillus niger, Fusarium soloni, which are the secondary causative agents, were cultured in SDA medium to make them ready for the study. MALDI-TOF MS was used to identification them according to their types. The minimum inhibitory concentration (MIC) values for Octenidine Dihydrochloride (OCT-D), Hypochlorous Acid (HOCl) and Terbinafine of the dermatophytes in the growing plaques were determined by the agar dilution method and the tube dilution method with reference to the broth microdilution method specified by the European Committee on Antimicrobial Susceptibility Testing (EUCAST). After MIC evaluations, the minimum fungicidal concentration (MFC) was evaluated. According to the MFC results, flow cytometry analysis was performed using SYTO 9 and PI dyes to examine the effects of OCT-D, HOCl and Terbinafine on cell viability. RESULTS: As a result of antifungal susceptibility tests performed on onychomycosis agents, the approximate MIC value for the agar dilution test was found to be 250 mg/l, 128 mg/l and 0,064 mg/l for OCT-D, HOCL and Terbinafine, respectively. As a result of the tube dilution test, the approximate MIC values were found to be 62,5 mg/l, 64 mg/l and 0,032 mg/l for OCT-D, HOCL and Terbinafine, respectively. As a result of viability analyzes performed by flow cytometry, it was observed that the values found using the tube dilution test could be more consistent. CONCLUSION: Since OCT-D and HOCl have MIC values much lower than commercially available concentrations and their lethality rates are high, it is thought that they can be a strong alternative for topical treatment with the tests to be performed.