Phakomatosis pigmentokeratotica is a rare neurocutaneous condition characterized by the combination of an organoid sebaceous nevus and speckled lentiginous nevus.James, William; Berger, Timothy; Elston, Dirk (2005). Andrews' Diseases of the Skin: Clinical Dermatology. (10th ed.). Saunders. .Freedberg, et al. (2003). Fitzpatrick's Dermatology in General Medicine. (6th ed.). McGraw-Hill. . It is an unusual variant of epidermal naevus syndrome. It was first described by Happle et al. It is often associated with neurological or skeletal anomalies such as hemiatrophy, dysaesthesia and hyperhidrosis in a segmental pattern, mild mental retardation, seizures, deafness, ptosis and strabismus.
Signs and symptoms Phakomatosis pigmentokeratotica consists of a speckled lentiginous naevus arranged in a checkerboard pattern and an organoid (epidermal) naevus associated with sebaceous differentiation. Other abnormalities are prevalent; these are usually neurological or skeletal and include hemiatrophy, segmental dysaesthesia and hyperhidrosis, mild intellectual disability, seizures, deafness, ptosis, and strabismus.
Causes Phakomatosis pigmentokeratotica is brought on by a multipotent progenitor cell's postzygotic HRAS mutation.
See also Skin lesion List of cutaneous conditions associated with increased risk of nonmelanoma skin cancer
References
Further reading
External links VisualDx