What is scleromyxedema?
Scleromyxedema (papular mucinosis) is characterized by a wide-spread eruption of small (2–3 mm), nonpruritic, waxy papules on the face, neck, upper trunk, distal forearms, and dorsal surface of the hands (sparing the palms). Involvement of skin overlying the eyebrows and forehead can give rise to leonine facies. Over 80% of individuals have an IgG monoclonal protein (usually IgG lambda), with 10% developing multiple myeloma. Thyroid studies are normal. The typical age of onset is 30 to 80 years and men and women are affected equally. Skin biopsies reveal a normal epidermis, a perivascular mononuclear cell infiltrate, mucin deposition in the papillary dermis, fibroblast proliferation, and fibrosis. Extracutaneous disease can be common, with concurrent myopathy, arthralgia/arthritis, and dysphagia, as well as neurologic, cardiac, pulmonary, and renal involvement. A severe form of neurologic involvement known as dermato-neuro syndrome consists of fever, seizure, and coma following a flu-like prodrome. Of interest, the etiology of extracutaneous disease is uncertain and cannot be solely explained by excessive mucin deposition in target organs.
