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Photoletter to the editor: Exogenous pigmentation after Diplopoda exposure leading to a dermatoscopic parallel ridge
Tainá Scalfoni Fracaroli1, Ludmilla Queirós Miranda2, Juan Piñeiro Maceira3
1Department of Dermatology, Hospital Central do Exército, Rio de Janeiro, RJ, Brazil;
Abstract:
The millipedes (also known as "gongolos") are arthropods characterized by a cylindrical body consisting of rings. When threatened, they release chemicals that can cause erythema and hyperpigmentation. We report the case of a patient who developed a darkened macule on the plantar region after stepping on a millipede. Dermatoscopic examination showed a parallel-ridge pattern, which is considered typical for acral melanoma. A detailed history was essential for the diagnosis, as the clinical and dermatoscopic features suggested a malignant melanocytic lesion.

