Waldenström Macroglobulinemia With an IgM-? Antiepidermal Basement Membrane Zone Antibody

Abstract

<h3>• Background.—</h3> Waldenström macroglobulinemia, a lymphoplasmacytoid cell malignant neoplasm associated with a monoclonal IgM paraprotein, has been associated with a number of cutaneous manifestations. On rare occasions, IgM deposits have been demonstrated in the epidermal basement zone of patients with WM. <h3>Observations.—</h3> We report the case of a patient with Waldenström macroglobulinemia and IgM-κ paraprotein who had development of an eruption of pruritic papules and demonstrated the following unusual immunopathologic findings: (1) deposits of IgM-κ in the epidermal basement membrane zone of lesional and nonlesional skin; (2) a circulating IgM-κ antiepidermal basement membrane zone antibody; and (3) binding of this circulating IgM-κ antiepidermal basement membrane zone antibody to both sides of 1 mol/L sodium chloride split skin. The cutaneous eruption cleared completely with oral psoralen with long-wave UV radiation in the A range (PUVA) therapy. <h3>Conclusions.—</h3> We present a patient with Waldenström macroglobulinemia who had a distinctive papular eruption and immunopathologic findings suggesting that his paraprotein has specificity for the epidermal basement membrane zone. (<i>Arch Dermatol.</i>1992;128:372-376)