Treatment of palmoplantar psoriasis with topical methoxsalen plus long-wave ultraviolet light

Fourteen patients with chronic plaque-type psoriasis involving the palms and soles and 14 patients with palmoplantar vesiculopustular dermatosis, including three cases of localized pustular psoriasis, were treated with topical application of methoxsalen, followed by exposure to long-wave ultraviolet energy (topical PUVA). Approximately two thirds of the patients with palmoplantar plaque-type psoriasis and half of those with vesiculopustular dermatosis responded with considerable improvement, as evidenced by flattening of plaques, decreased scaling and erythema, and decreased vesicle and pustule formation after 15 to 40 treatments. Complete clearing of the treated areas was achieved in five patients with palmoplantar psoriasis, three of whom had the pustular variety. Most patients required continued maintenance therapy with topical PUVA. The condition of the patients with palmoplantar vesiculopustular dermatosis, especially those with severe involvement, was more labile and more difficult to control with PUVA therapy than in those with chronic scaling plaques.