REPORT OF A CASE
A 4-year-old white girl presented with a patch of abnormal hair on the posterior part of her scalp that had been present since birth. There was some difficulty in brushing the affected area. On examination, a well-defined, 10-cm-diameter patch of abnormal hair was seen in the occipital region. The abnormal hair was tightly curled, and appeared thinner and lighter than the rest of the scalp hair (Figure 1). There were no skin or ocular abnormalities, nor any family history of hair abnormality. The light microscopic appearance of the hair shaft is shown in Figure 2.What is your diagnosis?DIAGNOSIS: Woolly hair nevus.
Woolly hair nevus is a rare condition that usually appears at birth or during the first 2 years of life. Both sexes are equally affected.1,2 In most of the cases, woolly hair is a nongenetically determined condition; however, hereditary cases have also been reported. Woolly hair nevi
Amichai B, Grunwald MH, Halevy S. A Child With a Localized Hair Abnormality. Arch Dermatol. 1996;132(5):579-580. doi:10.1001/archderm.1996.03890290113016