Palmoplantar keratodermas (PPK) comprise a heterogeneous group of keratinization disorders with hyperkeratotic thickening of palms and soles. Sporadic or acquired forms of PPKs and hereditary forms exist. The causes of acquired PPK vary, and include exposure to certain chemicals, side effects of certain drugs, and metabolic disorders. There is as yet no cure for hereditary PPK. In patients with acquired PPK, the cause should be treated or eliminated, if possible. In both instances, optimized treatment can lead to a significant improvement in symptoms. Topical therapy with urea-based ointments improves the skin's absorption of moisture and has keratolytic effects. Topical vitamin D therapy is another option.
Hereditary PPK are divided morphologically into four types; diffuse, focal, striate and punctate. PPK can be further subdivided histologically into epidermolytic and nonepidermolytic PPK.
