LAUSR

chophyton rubrum was isolated in culture. The patient was diagnosed with TI and treated with a 4-week course of terbinafine (250 mg/day) with full recovery. The previous incorrect treatment with corticosteroid or immunosuppressant agents makes TI a very challenging diagnosis, because it develops clinical features resembling cutaneous inflammatory diseases, such as eczema and psoriasis. In our experience, TI mostly affects elderly people probably because misdiagnosis is more common at this age as cutaneous dermatophyte infections are more frequent in younger patients. In this context, dermoscopy could play a key role in helping clinicians for differential diagnosis. In particular, there is a high confidence with dermoscopy for common inflammatory cutaneous diseases that may be confused with tinea incognito, such as psoriasis and eczema. As a matter of fact, the former typically shows at dermoscopy a prevalence of regularly distributed dotted vessels and white scales (Fig. 2a), while the latter often reveals yellowish crusts as a result of vesicle rupture (Fig. 2b). Concerning dermoscopy of TI, only one paper was published so far indicating that Morse code hair, as well as found in tinea capitis, could be seen in TI too, probably resulting from localized areas of ‘perforating’ fungal invasion of vellus hair also visible with direct microscopy. Conversely, the detection of black dots surrounded by a white halo as a consequence of vellus hair involvement has been previously described as a possible dermoscopic finding in tinea corporis, and it has been indicated as a marker of necessity of systemic antifungal treatment. TI could be considered as a misdiagnosed and severe tinea corporis, where the infection severity allows the deep penetration of dermatophyte in the skin and the secondary invasion of vellus hair. For that reason, although never described in literature so far, TI is supposed to frequently show at dermoscopy vellus hair involvement, although this assertion should be confirmed by larger studies.