A 39-year-old woman with Fitzpatrick skin phototype II and a history of melanoma in 2 first-degree relatives, was on digital dermoscopy follow-up for dysplastic nevus syndrome. She consulted for a rapid change in appearance and the onset of pruritus in a lesion that had been present on her back for years and that had been stable up to that time. She denied any history of trauma.

In the left lumbar region she presented a brown pigmented lesion of 5mm diameter, surrounded by an erythematous halo. Dermoscopy showed a melanocytic lesion with a homogeneous light-brown central area and peripheral network, with violaceous areas and scabs, surrounded by an erythematous-violaceous halo, from which it was separated by a band of healthy skin (Fig. 1).

Figure 1

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After 4 weeks of topical therapy with mupirocin, the halo disappeared (Fig. 1B), the pruritus resolved and after 2 years of follow-up the nevus remains unchanged.

Targetoid hemosiderotic nevus is a rare, benign self-resolving lesion that has been associated with trauma. Although clinically it can resemble melanoma, dermoscopy shows a nevus with a benign pattern, surrounded by an ecchymotic halo produced by the presence of dilated blood vessels, extravasation of red blood cells, and hemosiderin deposits in the papillary dermis.