Porokeratotic eccrine duct and hair follicle nevus

Coskey RJ, 1982

Unilateral or bilateral congenital or acquired linear hamartoma of the skin characterized by the characteristic histological phenomenon of the"cornoid lamella". The clinical picture may be associated with skeletal anomalies or other complex malformations.

Extremities, preferably the lower extremity.

Linear, unilateral or bilateral clinical picture with grouped or confluent, brownish, keratotic papules or plaques partly with central corneal plugs.

A characteristic feature of the Porokeratotic eccrine duct and hair follicle nevus is the so-called cornoid lamella, a columnar parakeratosis within an epidermis that is keratinized orthokeratotically. The parakeratotic columnar formations are limited to dilated follicle ostia (but can also occur interfollically).

1. Coskey RJ et al (1982) Porokeratotic eccrine duct and hair follicle nevus. J Am Acad Dermatol 6:940-943.
2. Goddard DS et al (2009) Widespread porokeratotic adnexal ostial nevus: clinical features and proposal of a new name unifying porokeratotic eccrine ostial and dermal duct nevus and porokeratotic eccrine and hair follicle nevus. J Am Acad Dermatol 61:1060. https://www.ncbi.nlm.nih.gov/pubmed/19664847
3. Llamas-Velasco M et al,(2015) Porokeratotic adnexal ostial naevus: review on the entity and therapeutic approach. J Eur Acad Dermatol Venereol 29:2032-2037.
4. Schüürmann M et al (2016) Unilateral linear dermatosis. J Dtsch Dermatol Ges 12: 1310-1312