Dermoscopic features in fungal melanonychia

Summary Background Data on the dermoscopic features of fungal melanonychia are limited. Aim To identify the dermoscopic features of fungal melanonychia. Methods We reviewed patient files, clinical history and dermoscopic images of all cases with a diagnosis of fungal melanonychia seen at our dermoscopy unit within the past year. Results In total, 14 cases with 20 involved nails were reviewed. The most common type of melanonychia was melanonychia striata (7/20). Multicoloured pigmentation was observed in 19 of the nails. The main dermoscopic pattern was homogeneous pigmentation; however, black pigmented aggregates, presenting as either coarse granules or pigmented clumps, accompanied this homogeneous pigmentation in 16 lesions. Matt black pigmentation, matt white pigmentation, yellow to brown pigmentation, black reverse triangle (wider at the distal than the proximal end), superficial transverse striation and blurred appearance were the other features. Conclusions We have identified a number of dermoscopic features appearing in fungal melanonychia, which should help in diagnosis of this disease.