“Nail-Like Appearance”: Characteristic Feature of Hair Fracture Caused by Hair Dye under Dermoscopy
A 39-year-old-woman consulted for neatly-broken hair after reddening her hair on forehead margin of the scalp with a 1-day history (Figure 1). (a) The broken ends curled slightly downward under polarized light (b) Analogous to nails used in construction (c) Which has not been observed in previous trichoscopy. The reddish-brown amorphous plaque that resemble excoriated lesions on the scalp and the similar color of surrounding dyed hairs (d) Highly indicated the diagnosis of hair fracture caused by hair dye . This was confirmed considering the absence of high-temperature perm history and should be in differential diagnosis from tinea capitis and trichotillomania.