A 3-year-old girl with thin hair.

CME EDUCATIONAL OBJECTIVES: 1.Identify the clinical features of loose anagen syndrome.2.Distinguish between loose anagen syndrome and other types of alopecia in a young child.3.Understand the natural history of loose anagen syndrome. A healthy 3-year-old white girl presented to the pediatric dermatology clinic for evaluation of thin hair. She was born with little hair and slowly grew thin blond hair. Her hair has always remained short, and she has only had one haircut. The patient's mother never noted any scalp abnormalities such as scale or dermatitis. The child does not seem to play with her hair. Her mother notes times when clumps of hair pull out without discomfort. A laboratory work-up prior to presentation revealed normal thyroid studies and an incidental iron deficiency anemia for which she was on oral iron replacement. There was no family history of alopecia, thin hair, or autoimmune disorders.