47
Keratodermas
• Three major types of involvement.
– Diffuse PPK: confluent over the entire palmoplantar surface; onset by early childhood in hereditary forms, with initial erythema evolving into thick, yellow hyperkeratosis that may be waxy or verrucous (Fig. 47.1).
Fig. 47.1 Diffuse palmoplantar keratoderma. A Non-epidermolytic keratoderma with sharp demarcation at the wrist and side of the thumb. B Non-epidermolytic keratoderma with greater thickness in sites of pressure. C Epidermolytic keratoderma with prominent erythema at the border. In general, epidermolytic and non-epidermolytic forms cannot be distinguished clinically. A, Courtesy, Julie V. Schaffer, MD; B, C, Courtesy, Alfons L. Krol, MD, and Dawn Siegel, MD.
– Focal PPK: primarily in areas of friction or pressure; the areata/nummular (oval) pattern affects the soles (Fig. 47.2A) > palms; the striate (linear) pattern extends from the palms to the volar fingers (Fig. 47.2B).
Fig. 47.2 Focal palmoplantar keratoderma. A Areata type on the soles. B Striate type on the palm. A, Courtesy, Alfons L. Krol, MD, and Dawn Siegel, MD.
– Punctate PPK: small (≤1 cm) keratotic papules on the palms and soles; onset is usually in adolescence or early adulthood, with initial pinhead-sized translucent papules that may become larger and callus-like (Fig. 47.3).
Fig. 47.3 Punctate palmoplantar keratoderma. Keratotic papules, some coalescing to form plaques, on the palm (A) and sole (B). A, Courtesy, Kalman Watsky, MD.
• Other possible features include hyperhidrosis, an erythematous border (see Fig. 47.1C), extension beyond the palmoplantar skin (e.g. onto dorsal hands/feet; ‘transgrediens’), digital constriction bands (pseudoainhum; see Fig. 47.4B
