Synonym: keratosis follicularis
Inheritance: autosomal dominant
Chromosome: 12q23-q24.1
Gene affected: ATP2A2
Mechanism of defect: impaired adhesion between keratinocytes
Clinical features:
(1) reddish-brown pruritic crusted papules in a seborrheic distribution
(2) nail changes (V-shaped nicking, longitudinal ridging, longitudinal bands)
(3) mucosal lesions
(4) verruciform (wart-like) flat papules on the dorsal surface of the feet and hands
(5) punctate keratosis on the soles and palms (palmoplantar keratoderma)
The skin lesions may become worse following:
(1) exposure to heat
(2) after sweating
(3) following sunlight exposure
(4) during pregnancy.
The keratotic papules may have a foul odor during the summer.
