Follicular spicules of the nose: a peculiar cutaneous manifestation of multiple myeloma with cryoglobulinemia.

We describe a patient with multiple myeloma and cryoglobulinemia who had spicules with a horny appearance in the follicular openings of the face, particularly on the nose. Histopathologic study demonstrated that these spicules consisted of eosinophilic homogeneous deposits in the intercellular spaces between keratinocytes in the upper layers of the follicular infundibulum. Direct immunofluorescence, ultrastructural, and biochemical investigations revealed that these eosinophilic deposits were cryoprecipitates composed of IgG-kappa with electrophoretic characteristics identical to those of the paraprotein present in the serum of the patient. Hence we believe that these lesions are best referred to as pseudohyperkeratotic spicules of the nose, and that they are a characteristic cutaneous manifestation of patients with multiple myeloma and cryoglobulinemia.