Common Dermatophyte Infections Tinea Pedis and Onychomycosis

A 50-year-old man had a long-standing rash on both soles. The patient’s toenails were yellow and dystrophic. These physical findings strongly suggested moccasin- variety tinea pedis and onychomycosis (also called tinea unguium)—two often concurrent infections.

A potassium hydroxide examination confirmed the suspected diagnoses.

Moccasin-variety tinea pedis is virtually impossible to cure; however, it can be controlled with topical antifungals. Onychomycosis can be treated with oral terbinafine, 250 mg bid, for the first 7 days of 4 consecutive months.

This infection is potentially curable but difficult to treat, because therapy is expensive, associated with rare but potentially dangerous side effects, and ineffective in at least 35% of patients.¹ In addition, most older patients with onychomycosis are susceptible to the infection, as they are to tinea pedis.

Even with adequate treatment, reexposure is inevitable because the organism is ubiquitous in the environment.