[Loose anagen hair].

We report on a 5-year-old girl whose hair could be pulled out with no effort and without causing pain. Occipital alopecia in a patchy pattern and with no sign of scalp inflammation or scarring was noted. A trichogram from the clinically involved area disclosed a striking predominance of anagen hair with absence of external root sheaths. Histological examination of the hair suggests abnormal premature keratinization of the inner root sheath, resulting in the loss of its anchoring function between the hair shaft and the follicle. Zaun first reported this new type of hair loss in children in 1984. The name loose anagen hair of childhood has recently been suggested for this disease. The differential diagnosis includes alopecia areata, trichotillomania, and congenital hypotrichosis.