The effect of antifungal medications on the sensitivity of dermatophyte culture

Recently, there has been an increase in the incidence of dermatophyte infections and increasing resistance to antifungal drugs. The current study aimed to highlight the effects of antifungal medications on culture sensitivity. This was a case-control study of patients with clinically evident dermatophyte infection and positive KOH microscopic examination. The culture was performed using Dextrose Sabouraud Agar (DSA). Patients were divided according to their treatment status at the time of presentation: patients on antifungal drugs, patients who stopped antifungal drugs, patients using topical steroids and patients not using any form of treatment (the control group). The number of enrolled patients was 133. Patients who did not receive any type of treatment showed the highest percentage 18/33 (54.5%) of fungal growth on culture media. Patients who were using systemic with or without topical antifungal drugs at the time of presentation or stopped them within one month, had statistically significant lower culture success rates (10.0% and 10.5%), respectively. Systemic ± topical antifungal drugs stopped more than one month before sampling had no significant effect on culture results with a success rate (33.3%). Patients with topical antifungal drugs had high positive culture rates (33.3%) for those continuing on topical, 50.0% for stopped < 2 weeks, 57.1% for stopped > 2 weeks). Patients on topical corticosteroids had low positive culture rates (28.6%) as compared to control, but not statistically significant. In conclusion, systemic antifungal medications alone or with topical formulation can significantly affect culture sensitivity, while topical antifungal drugs alone and topical corticosteroids have no significant effect.