Dermoscopy revealing a case of Tinea Nigra.

Dermoscopy has being used over the past twenty years as a noninvasive aid in the diagnosis of innumerable skin conditions, including infectious diseases and infestations (Entodermoscopy).Tinea nigra is a superficial phaeohyfomycosis that affects mainly the glabrous skin of palms and soles. We describe a 14 year-old girl with a three-month history of an enlarging brown patch of her hand diagnosed as Tinea Nigra following clinical and dermoscopy examination.These images emphasize the importance of dermoscopy as a diagnostic tool in the daily routine of dermatologists.

The term Entodermoscopy was coined by Zalaudek et al. for the use of dermoscopy as an aid in the in vivo diagnosis of skin infections and infestations.[1] Specific dermoscopic patterns have been recently described for several of these conditions with a view to facilitating their diagnosis.

One of these conditions is Tinea nigra. First identified in 1891 by Alexandre Cerqueira, in Bahia, Brazil, and described in 1916 by his son as Keratomycosis nigricans Palmaris; this superficial phaeohyphomycosis is caused by the mould Hortae werneckii that occurs mainly in tropical or subtropical areas.[1-5] The condition is characterized clinically by a gradually enlarging, irregularly pigmented macula on the palms and soles, which can be confused with melanocytic lesions.[1,6,7]

Our report concerns a 14 year-old girl who presented with a 3-month history of a slow-growing asymptomatic pigmentation on her palm. Clinical examination revealed a well-demarcated, nondesquamative, irregularly pigmented macula on her left palm (Figure 1). Dermoscopy of the lesion showed superficial fine, wispy pigmented spicules. These spicules did not respect the dermatoglyphic lines, thus confirming the Tinea nigra diagnosis (Figure 2). The patient was treated with ciclopirox olamine 1% cream, twice daily, with complete clinical resolution after three weeks of treatment.

FIGURE 1

Tinea nigra: A well-demarcated, nondesquamative, irregularly pigmented macula on the left hand

FIGURE 2

Dermoscopy 10X: Superficial fine, wispy pigmented spicules

The characteristic Tinea nigra dermoscopic pattern was first described by Gupta et al. in 1997 as 'pigmented spicules', which form an almost reticulated patch, as in our case described above.[8]

Our report emphasizes the importance of dermoscopy in the diagnosis of Tinea nigra.