A recent study published in Medical Mycology investigated viability of pathogenic fungi during topical administration of 1% luliconazole (LLCZ). 

This study assessed 13 tinea pedis patients found to be positive on KOH examination by mycological examinations and quantitative real-time polymerase chain reaction (PCR) targeted internal transcribed spacer (ITS) in ribosomal RNA gene, at the initial visit and after 2 and 4 weeks of treatment.

The results revealed that the average copy number of ITS DNA had significantly decreased to 22.9% at 2 weeks and to 4.8% at 4 weeks, compared with the initial visit. Moreover, LLCZ topical treatment could defeat most pathogenic dermatophytes in the scales within 4 weeks.

The findings indicated that the application of antifungal agents can lead to complete cure by eliminating pathogenic fungi – assumed to be in hyphae form, in the lesion site. Furthermore, antifungal agents can aid in renewal of the infected stratum corneum and nail if surviving pathogenic fungi remain in a dormant state—that is alive but not growing. Hence, topical or oral antifungal treatment should be continued until desquamation of the infected site because dermatophytosis can recur by germination of surviving arthroconidia.

The findings demonstrated the cure mechanism of tinea pedis by LLCZ topical treatment. Approximately 95% of pathogenic dermatophytes in the scale were eliminated after 4 weeks of 1% LLCZ topical treatment, and this therapy rendered approximately 5% of surviving dermatophytes in the dormant state, until desquamation of the infected scales.

Source: Medical Mycology. 2020 Apr; 58(3): 401-403. doi: 10.1093/mmy/myz056