Curly hair nevus Q82.5

Rare ectodermal abnormality with circumscribed, congenital, permanent growth disorder of the hair shaft. Formation of an area of frizzy hair, possibly multilocular occurrence. Remarkably, the malformation postnatally shows up as a less hairy area at first, so that initially, an aplasia cutis congenita is more likely.

Thin, light, finely curled, non-combed hair in areas of varying size and configuration. These areas stand out clearly from the healthy environment (colour [light hair colour], structure, consistency). The hair has axial twists of 180 degrees and is structurally similar to sheep's wool. The hairs are elliptical or oval and have a reduced diameter. In 50% of cases there are associations with linear epidermal nevi. Other associated malformations (eye malformations, disorders in speech development, tooth anomalies, delayed bone growth) are known (Behle V et al. 2014).

Naevoid bundle hair; Pili torti; Pili canaliculi.

Acquired curly hair (see curly hair, acquired)

1. al-Harmozi SA et al (1992) Woolly hair nevus syndrome. J Am Acad Dermatol 27(2 Pt 1): 259-260
2. Behle V et al(2014) Developmental abnormalities and nevi of the scalp. Dermatologist 65:1022-1029.
3. Gosain AK et al (2001) Giant congenital nevi: a 20-year experience and an algorithm for their management. Plast Reconstr Surgery 108: 622-636
4. Stieler W et al (1992) Multiple woolly hair nevi with linear epidermal nevus and persistent pupillary membrane. dermatologist 43: 441-445
5. Tay YK et al (1996) Epidermal nevus syndrome: association with central precocious puberty and woolly hair nevus. J Am Acad Dermatol 35(5 Pt 2): 839-842
6. Wise F (1927) Wooly hair nevus. A peculiar Form of birthmark of hair of the scalp, hitherto undescribed, with report of two cases. Med J Rec 125: 545-547