Tazarotene as alternative topical treatment for onychomycosis.
BACKGROUND
Distal and lateral onychomycoses are the most frequent forms of onychomycosis, causing subungual hyperkeratosis that usually limits local penetration of antimycotic drugs. Tazarotene exerts anti-inflammatory and immune-modulating activities toward both infective agents and damaged keratinocytes. Given the well-documented efficacy of tazarotene on hyperkeratotic nail psoriasis, we investigated its therapeutic use in onychomycosis.


METHODS
We designed a preliminary open clinical trial in patients affected by distal and lateral subungual onychomycosis of the toenails and verified the fungistatic activity of tazarotene in vitro. Fifteen patients were treated with topical tazarotene 0.1% gel once per day for 12 weeks. Mycological cultures and potassium hydroxide stains of nail samples were performed at the beginning and at the end of the study. Treatment was considered effective when clinical healing and negative mycological culture were obtained. Onycholysis, nail bed discoloration, and subungual hyperkeratosis were measured using standardized methodologies and analyzed by means of Mann-Whitney test and analysis of variance. Fungistatic activity of tazarotene was evaluated by disk diffusion assay.


RESULTS
Six patients (40%) reached a mycological cure on target nail samples already after 4 weeks of treatment. Complete clinical healing and negative cultures were reached in all patients at week 12, with a significant improvement of all clinical parameters of the infected nails. Disk diffusion assay after 48 hours of incubation with tazarotene solution showed a central area of inhibition in all examined fungal cultures.


CONCLUSIONS
Our results documented a good clinical outcome using topical tazarotene 0.1% gel in distal and lateral subungual onychomycosis and its fungistatic activity of tazarotene in vitro. The majority of patients appeared cured at a 6-month follow-up. The efficacy and safety of tazarotene must be confirmed on a larger number of patients, although already documented in nail psoriasis patients often affected by onychomycosis.
Department of Dermatology, Policlinic Tor Vergata, Rome, Italy.
Elena
E
Campione
Department of Biomedicine and Prevention, Policlinic Tor Vergata, Rome, Italy.
Evelin Jasmine
EJ
Paternò
Department of Biomedicine and Prevention, Policlinic Tor Vergata, Rome, Italy ; Department of Anatomic Pathology, Policlinic Tor Vergata, Rome, Italy.
Gaetana
G
Costanza
Department of Dermatology, Policlinic Tor Vergata, Rome, Italy.
Laura
L
Diluvio
Department of Dermatology, Policlinic Tor Vergata, Rome, Italy.
Isabella
I
Carboni
Department of Microbiology, University of Rome Tor Vergata, Rome, Italy.
Daniele
D
Marino
Department of Microbiology, University of Rome Tor Vergata, Rome, Italy.
Cartesio
C
Favalli
Department of Dermatology, Policlinic Tor Vergata, Rome, Italy.
Sergio
S
Chimenti
Department of Dermatology, Policlinic Tor Vergata, Rome, Italy.
Luca
L
Bianchi
Department of Biomedicine and Prevention, Policlinic Tor Vergata, Rome, Italy ; Department of Anatomic Pathology, Policlinic Tor Vergata, Rome, Italy.
Augusto
A
Orlandi
D000287:Administration, Topical; D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009539:Nicotinic Acids / Q000008:administration & dosage* / Q000627:therapeutic use*; D014009:Onychomycosis / Q000188:drug therapy*; D055815:Young Adult; D012176:Retinoids
D009539:Nicotinic Acids; C086827:tazarotene; D012176:Retinoids
antiproliferative agent; fungistatic activity; retinoids