Palmoplantar Keratoderma, Punctate Type Ii

Nomenclature

Stevens et al. (1996) classified this disorder as type II punctate PPK (PPKP2), type I being the Buschke-Fischer-Brauer disorder (see PPKP1A; 148600), and type III being acrokeratoelastoidosis (PPKP3; 101850). The designation PPPP was proposed by Chernosky (1986).

Clinical Features

This condition was first described by Brown (1971) as punctate keratoderma.

Schiff and Hughes (1974) described a family in which many members, both male and female, had palmoplantar lesions that became manifest at or around puberty. Male members of the family also presented with facial sebaceous hypoplasia. The keratosis was described as 'acuminata,' or spiny.

Sakas and Gentry (1985) reported a 60-year-old man of Korean origin who presented with a 15-year history of numerous asymptomatic 1- to 3-mm pits with keratotic plugs on the plantar aspects of both feet and on the palms of both hands. Histologic studies showed distinct epidermal depressions containing cornoid lamellae. The authors noted that cornoid lamellation represents a disordered progression of epidermal keratinocytes to cornification. There was no family history of the disorder in their Korean patient.

Lestringant and Berge (1989) reported a Saudi family in which 7 members in 3 generations had porokeratosis punctata palmaris et plantaris. All 7 affected members were male, and consanguinity was denied. Spinous keratoses were limited to the volar aspects of the hands and feet. Nails, teeth, and sweating were normal. Lesions were said to have appeared on the hands in the early twenties and on the feet a bit later. The elementary lesion was a tiny keratotic spine. Histologic study showed columnar parakeratosis that resembled the cornoid lamella of porokeratosis.

Inheritance

Stevens et al. (1996) indicated that PPKP2 is an autosomal dominant disorder.