Successful treatment of lichen myxoedematosus with PUVA photochemotherapy.

Lichen myxoedematosus is an unusual disorder of unknown etiology and pathogenesis. Although several treatments have reportedly been tried, therapeutic efficacies are variable and unsatisfactory. A patient with severe skin changes of this disease was successfully treated with PUVA photochemotherapy. PUVA therapy was carried out using 30 mg of 8-methoxypsoralen orally, and subsequent exposure to UVA starting at 4 J/cm2. The eruption disappeared almost completely after 35 treatments at a cumulative dose of 202 J/cm2. Histologically, mucin deposition was greatly diminished after the therapy. The photochemotherapy may exert its effect directly by inhibiting proliferation of fibroblasts and synthesis of mucopolysaccharides, and also indirectly by immunomodulating action.