Optimizing Topical Antifungal Therapy for Superficial Cutaneous Fungal Infections: Focus on Topical Naftifine for Cutaneous Dermatophytosis

November 2013 | Volume 12 | Issue 11 | Supplement Individual Articles | 165 | Copyright © November 2013


James Q. Del Rosso DO FAOCDa and Leon H. Kircik MDb

aTouro University College of Osteopathic Medicine, Henderson, NV;
Las Vegas Skin and Cancer Clinics/West Dermatology Group, JDRx Dermatology LLC, Henderson, NV
bMount Sinai Medical Center, New York, NY; Indiana University School of Medicine, Indianapolis, IN;
Physicians Skin Care, PLLC, Louisville, KY

Abstract
Superficial cutaneous fungal infections (SCFIs) are commonly encountered in clinical practice in the United States, and comprise infections of the skin by dermatophytes and yeasts. The most common organisms causing SCFI are dermatophytes, especially Trichophyton spp. With the exception of onchomycosis and tinea capitis, most cases of SCFIs are amenable to properly selected topical antifungal therapy used over an adequate period of time.

A variety of topical antifungal agents are available for the treatment of SCFIs, and they encompass a few major chemical classes: the polyenes (ie, nystatin), imidazoles (ie, ketoconazole, econazole, oxiconazole, etc), allylamines (ie, naftifine, terbinafine), benzylamines (ie, butenafine), and hydroxypyridones (ie, ciclopirox). The 2 major classes that represent the majority of available topical antifungal agents are the azoles and the allylamines. Overall, the allylamines are superior to the azoles in activity against dermatophytes, although both are clinically effective. The reverse is true against yeasts such as Candida spp and Malassezia spp, although topical allylamines have proven to be efficacious in some cases of tinea versicolor and cutaneous candidiasis.

Naftifine, a topical allylamine, is fungicidal in vitro against a wide spectrum of dermatophyte fungi and has been shown to be highly effective against a variety of cutaneous dermatophyte infections. Rapid onset of clinical activity and favorable data on sustained clearance of infection have been documented with naftifine. The more recent addition of naftifine 2% cream has expanded the armamentarium, with data supporting a clinically relevant therapeutic reservoir effect after completion of therapy.

J Drugs Dermatol. 2013;12(suppl 11):s165-s171.

INTRODUCTION

Superficial cutaneous fungal infections (SCFIs) are commonly encountered in clinical practice in the United States.1 The majority of etiologic fungal organisms associated with the common SCFIs are caused by dermatophytes, including Tricophyton spp (especially Trichophyton rubrum), Microsporum spp, and Epidermophyton floccosum.1-3 Dermatophyte infections can affect both children and adults, and demonstrate an affinity for keratin with the ability to infect glabrous skin, hair-bearing skin, hair shaft, and the nail unit.3 Specific dermatophyte infections will be discussed in more detail later and are a primary focus of this article. The most common SCFIs induced by yeasts are tinea versicolor, which is caused by a variety of Malassezia spp, and cutaneous candidiasis, most often caused by Candida albicans.4-9

Overview of Superficial Cutaneous Fungal Infections

Although this article will focus on cutaneous dermatophyte infections, an overview of the common SCFIs is very relevant as there can be overlap in the differential diagnosis and available therapeutic options.
Cutaneous Yeast Infections

Tinea versicolor

Tinea versicolor, also referred to as pityriasis versicolor, predominantly affects predisposed adults of either gender, who periodically experience conversion of the commensal saprophytic yeast form (Pityrosporum spp such as Pityrosporum ovale) to its mycelial (hyphal) form (Malassezia spp), with subsequent proliferation most commonly on the trunk, proximal extremities, and lower neck.4,5 Among the more common mycelial forms identified on patients with tinea versicolor are Malassezia globosa (50%-60%), Malassezia sympodialis (3%-59%), Malassezia furfur (1%-10%) and Malassezia sloofiae (1%-10%), although the involved species may vary geographically, and the prevalence is markedly increased in tropical climates with high ambient humidity.4,5 Patients presenting with tinea versicolor are generally immunocompetent, and the factors that incite initial emergence and subsequent recurrences are usually inexplicable.4,5 However,immunocompromised patients, such as those with human immunodeficiency virus (HIV) infection, are predisposed to the development of tinea versicolor, tend to exhibit more widespread