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Updated: Jun 11, 2026

Flat Mount Imaging of Mouse Skin and Its Application to the Analysis of Hair Follicle Patterning and Sensory Axon Morphology
Published on: June 25, 2014
[Cutaneous pili migrans]
1MMS, Service de dermatologie, Huangpu Hospital of The First Affiliated Hospital, Sun Yat-sen University, 183, Huangpu Road E., Guangzhou 510700, P. R. China. luodq@mail.sysu.edu.cn
Introduction:
Cutaneous pili migrans, caused by a hair shaft or fragment embedded in the superficial skin, and occasionally in the middle dermis, is a rare condition characterized by creeping eruption with a black line at the advancing end, which resembles the lesion associated with cutaneous larva migrans.
Case Report:
We present the case of a 38-year-old Chinese housewife with a 30-day history of painfully and slowly moving black linear eruption on the dorsal aspect of her left foot. The more she walked, the further the line extended and the more pain she felt, particularly on walking rapidly. A black hair shaft was removed from the lesion, which healed completely.
Discussion:
Pili migrans is an extremely rare condition with only 22 cases being reported to date. The hair shaft penetrates into the superficial layers of the epidermis following injury or occasionally for no known reason. The spectacular clinical picture is similar to that seen in the interdigital spaces of hairdressers in whom there are only small hair fragments on occasion, with no movement of the lesion.
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