Poorly growing hair in a child

A healthy 5-year-old Caucasian girl presented to the pediatric dermatology clinic for poor hair growth. The patient's father described slow hair growth and finely textured hair since birth. The patient had her first haircut 1 month before presentation. The family denied bald areas on the scalp, significant hair shedding, and sores on the scalp. The child did not scratch at her scalp or pull her hair. She are a normal diet and had normal growth and development otherwise. She was not taking any medications or over-the-counter supplements. There was no family history of hair disorders. On physical examination, the patient had short, fine, reddish blond hair that was of different lengths (Figure 1). There were no papules, pustules, scale, or crust on her scalp. Lymphadenopathy was absent. She had normal eyelashes and eyebrows. There were no lesions on her oral mucosa. No tooth or nail abnormalities were present. The rest of the physical examination was normal. The hair pull test resulted in 4 easily pulled hairs (3 anagen and 1 telogen). A hair mount was performed (Figure 2). The hair mount analysis revealed anagen hairs with distorted bulbs and ruffled cuticles extending a short distance distally from the bulb, consistent with loose anagen hair (Figure 2). All of the anagen hairs on the pull test demonstrated the above findings. Based on the patient's clinical presentation and the findings seen on light microscopy of the hair mount preparation, the patient was diagnosed with loose anagen syndrome.