Efficacy of Lasers for the Management of Dermatophyte Toenail Onychomycosis.

ABSTRACT

BACKGROUND: Onychomycosis is a chronic fungal nail infection caused predominantly by dermatophytes, and less commonly by nondermatophyte molds and Candida species. Onychomycosis treatment includes oral and topical antifungals, the efficacy of which is evaluated through randomized, double-blind, controlled trials for US Food and Drug Administration approval. The primary efficacy measure is complete cure (complete mycologic and clinical cure). The secondary measures are clinical cure (usually ≤10% involvement of target nail) and mycologic cure (negative microscopy and culture). Some lasers are US Food and Drug Administration approved for the mild temporary increase in clear nail; however, some practitioners attempt to use lasers to treat and cure onychomycosis. METHODS: A systematic review of the literature was performed in July of 2020 to evaluate the efficacy rates demonstrated by randomized controlled trials of laser monotherapy for dermatophyte onychomycosis of the great toenail. RESULTS: Randomized controlled trials assessing the efficacy of laser monotherapy for dermatophyte toenail onychomycosis are limited. Many studies measured cure rates by means of nails instead of patients, and performed only microscopy or culture, not both. Only one included study reported mycologic cure rate in patients as negative light microscopy and culture (0%). The combined clinical cure rates in short- and long-pulsed laser studies were 13.0%-16.7% and 25.9%, respectively. There was no study that reported the complete cure rate; however, one did report treatment success (mycologic cure [negative microscopy and culture] and ≤10% clinical involvement) in nails as 16.7%. CONCLUSIONS: The effectiveness of lasers as a therapeutic intervention for dermatophyte toenail onychomycosis is limited based on complete, mycologic, and clinical cure rates. However, it may be possible to use different treatment parameters or lasers with a different wavelength to increase the efficacy. Lasers could be a potential management option for older patients and onychomycosis patients with coexisting conditions such as diabetes, liver, and/or kidney diseases for whom systemic antifungal agents are contraindicated or have failed.