Abstract
Palmoplantar keratodermas are a heterogeneous group of disorders characterized by abnormal thickening of the palms and soles.
Autosomal recessive and dominant, X-linked, and acquired forms have all been described.
Types
Clinically, three distinct patterns of palmoplantar keratoderma may be identified: diffuse, focal, and punctate.
Types | Diffuse
Diffuse palmoplantar keratoderma is a type of palmoplantar keratoderma that is characterized by an even, thick, symmetric hyperkeratosis over the whole of the palm and sole, usually evident at birth or in the first few months of life. Restated, diffuse palmoplantar keratoderma is an autosomal dominant disorder in which hyperkeratosis is confined to the palms and soles. The two major types can have a similar clinical appearance:
- "Diffuse epidermolytic palmoplantar keratoderma" (also known as "Palmoplantar keratoderma cum degeneratione granulosa Vörner," "Vörner's epidermolytic palmoplantar keratoderma", and "Vörner keratoderma") is one of the most common patterns of palmoplantar keratoderma, an autosomal dominant condition that presents within the first few months of life, characterized by a well-demarcated, symmetric thickening of palms and soles, often with a "dirty" snakeskin appearance due to underlying epidermolysis.
- "Diffuse nonepidermolytic palmoplantar keratoderma" (also known as "Diffuse orthohyperkeratotic keratoderma," "Hereditary palmoplantar keratoderma," "Keratosis extremitatum progrediens," "Keratosis palmoplantaris diffusa circumscripta," "Tylosis," "Unna–Thost disease", and "Unna–Thost keratoderma") is inherited as an autosomal dominant condition and is present from infancy, characterized by a well-demarcated, symmetric, often "waxy" keratoderma involving the whole of the palms and soles.
Types | Focal
Focal palmoplantar keratoderma, a type of palmoplantar keratoderma in which large, compact masses of keratin develop at sites of recurrent friction, principally on the feet, although also on the palms and other sites, a pattern of calluses that may be discoid (nummular) or linear.
- " Focal palmoplantar keratoderma with oral mucosal hyperkeratosis" (also known as "Focal epidermolytic palmoplantar keratoderma," "Hereditary painful callosities," "Hereditary painful callosity syndrome," "Keratosis follicularis," "Keratosis palmoplantaris nummularis", and "Nummular epidermolytic palmoplantar keratoderma") is an autosomal dominant keratoderma that represents a clinical overlap syndrome with pachyonychia congenita type I but without the classic nail involvement.
Types | Punctate
"Punctate palmoplantar keratoderma" is a form of palmoplantar keratoderma in which many tiny "raindrop" keratoses involve the palmoplantar surface, skin lesions which may involve the whole of the palmoplantar surface, or may be more restricted in their distribution.
- Type 1: "Keratosis punctata palmaris et plantaris" (also known as "Autosomal-dominant hereditary punctate keratoderma associated with malignancy," "Buschke–Fischer–Brauer disease," "Davis Colley disease," "Keratoderma disseminatum palmaris et plantaris," "Keratosis papulosa," "Keratoderma punctatum," "Keratodermia punctata," "Keratoma hereditarium dissipatum palmare et plantare," "Palmar and plantar seed dermatoses," "Palmar keratoses," "Papulotranslucent acrokeratoderma," "Punctate keratoderma," "Punctate keratoses of the palms and soles," and "Maculosa disseminata") is a skin condition, an autosomal dominant palmoplantar keratoderma with variable penetrance, characterized clinically by multiple, tiny, punctate keratoses over the entire palmoplantar surfaces, beginning over the lateral edge of the digits. It has been linked to 15q22-q24.
- Type 2: "Spiny keratoderma" (also known as "Porokeratosis punctata palmaris et plantaris," "Punctate keratoderma," and "Punctate porokeratosis of the palms and soles") is an autosomal dominant keratoderma of late onset that develops in patients aged 12 to 50, characterized by multiple tiny keratotic plugs, mimicking the spines on a music box, involving the entire palmoplantar surfaces.
- Type 3: "Focal acral hyperkeratosis" (also known as "Acrokeratoelastoidosis lichenoides," and "Degenerative collagenous plaques of the hand") is a late-onset keratoderma, inherited as an autosomal dominant condition, characterized by oval or polygonal crateriform papules developing along the border of the hands, feet, and wrists. It is considered similar to Costa acrokeratoelastoidosis.
Genetics
Epidermolytic palmoplantar keratoderma has been associated with keratin 9 and keratin 16.
Nonepidermolytic palmoplantar keratoderma has been associated with keratin 1 and keratin 16.
Treatment
Usually, a common form of treatment for the condition is a type of hand cream which moisturises the hard skin. However, currently the condition is incurable.