What is marginal keratoderma?
Marginal keratoderma is a form of papular palmoplantar keratoderma in which there are small firm warty or pearly papules on the sides of the hands and, in some cases, feet.
How is marginal keratoderma classified?
There are inherited and acquired forms of marginal keratoderma.
Inherited marginal keratoderma
The inherited form of marginal keratoderma is acrokeratoelastoidosis, which was first described by Costa in 1953; hence, it is sometimes called Costa acrokeratoelastoidosis. It affects both hands and feet.
Focal acral keratosis is a variant of acrokeratoelastoidosis.
Acquired marginal keratoderma
The acquired form of marginal keratoderma is often called keratoelastoidosis marginalis and is more common than acrokeratoelastoidosis.
Keratoelastoidosis marginalis is characterised by keratotic papules on the sides of the index fingers and thumbs in patients who have had a lot of exposure to the sun.