Creeping hair: an isolated hair burrowing in the uppermost dermis resembling larva migrans

A 55-year-old Japanese male presented with a slowly moving linear erythema that looked like an eruption of creeping disease, or cutaneous larva migrans. The eruption extended linearly along Langer's line of the lateral side of the abdomen to the lower back, leaving wave-like erythema. In the top third of the erythematous eruption, close examination demonstrated a black thin line, which was revealed to be a hair shaft by a shallow incision of the skin. After removal of the hair, the eruption diminished immediately, leaving a slight pigmentation. An ingrown pubic hair seemed to have migrated with the lower end forward along Langer's line, because of the arrangement of hair cuticle and the force of body motion. Linearly moving erythematous eruptions that look like that of larva migrans should be differentiated from creeping hair by close examination detecting burrowing hair.