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Occupation-related pigmented macules on the sole with parallel-ridge pattern on dermatoscopy
M Tanioka1, Y Matsumura, A Utani
1Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan. mtanioka@kuhp.kyoto-u.ac.jp
Abstract:
27-year-old man presented with pigmented macules on the right sole, which showed a parallel-ridge pattern on dermatoscopy. His work for a chemical company involved handling para-phenylenediamine. Histological examination of a biopsy from a lesion did not find any proliferation of atypical melanocytes. Shaving the cornified layer of the lesions with a surgical knife resulted in the disappearance of macules. We speculate that para-phenylenediamine on the sole of the patient's work boot might have become blotted to the cornified layer of the cutis. This report adds a new occupation-related differential diagnosis for skin diseases showing a parallel-ridge pattern on dermatoscopy.
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