Wooly hair nevus

Abstract

Woolly hair nevus is a rare condition characterized by a structural anomaly of the hair, restricted to certain areas of the scalp. The hair becomes coiled and slightly hypopigmented. The term woolly hair refers to changes that affect all the scalp and has a hereditary character. We present a case of woolly hair nevus, that developed at the age of 2 years, associated with dental diastema and verrucous epidermal nevus.

Isolated straight hair nevus in a White child

“…Our case is the first straight hair nevus in a White child without other anomaly at the age of 6 months. We suggest a postzygotic mutation causing a mosaic disorder like already suggested in isolated wooly hair nevus …”

Wooly hair nevus, Post's Type 2

“…This usually appears in the first few years of life, but cases occurring in adolescence have also been reported . Wooly hair nevus was classified into the following subtypes by Post‐Type 1—without any cutaneous involvement; Type 2—associated with linear verrucous epidermal nevus; Type 3—which occurs in young adults with scalp hair that resembles pubic hair . Like the index case, almost half of wooly hair nevus are associated with linear epidermal nevi located on ipsilateral face, neck, or trunk .…”

“…Dental abnormalities like recurrent cavities and diastema have been reported. Hemangiomas and café au lait macules may also be seen in association …”

“…It is often associated with extracutaneous features like arrhythmogenic cardiac abnormalities and palmoplantar keratoderma. Wooly hair can also be seen in cardiofaciocutaneous syndromes associated with facial dysmorphism …”

“…Hemangiomas and caf e au lait macules may also be seen in association. 4 This should not be mistaken with wooly hair syndrome, which is an inherited disorder (autosomal dominant and autosomal recessive variants have been described) characterized by the presence of generalized wooly hair all over the scalp. It is often associated with extracutaneous features like arrhythmogenic cardiac abnormalities and palmoplantar keratoderma.…”