In-Office Diagnosis of Cutaneous Mycosis: A Comparison of Potassium Hydroxide, Swartz-Lamkins, and Chlorazol Black E Fungal Stains

Cutaneous mycosis represents the most common type of skin infection and accounts for up to 17% of dermatology office visits. Wet-mount examination using direct microscopy is routinely used in the office to rapidly and cost-effectively detect fungal elements in dermatophytosis, pityriasis versicolor, and candidiasis. Three commonly used solutions for fungal preparation are potassium hydroxide (KOH), Swartz-Lamkins, and chlorazol black E. Although many experienced clinicians support a favorite stain, no analysis has been conducted to illustrate the differences between these stains. We present 3 photomicrographs of the fungal preparation from a patient with tinea corporis and highlight the characteristic features of each reagent.