A case of generalized scleromyxedema that responded to IVIG monotherapy
J Am Acad Dermatol
A 49-year-old African-American female presented with a mildly pruritic rash with an initial biopsy showing changes suggestive of interstitial granuloma annulare versus papular mucinosis. Despite treatment, her lesions continued to disseminate, and a second biopsy finally confirmed the clinical diagnosis of scleromyxedema. Further work-up revealed elevated serum kappa chains, and a subsequent bone marrow biopsy demonstrated a silent 10-15% plasma cell myeloma. She was started on IVIG 2 g/kg spread contiguously over five days once a month for six months. She received three cycles so far, which has resulted in dramatic improvement of her cutaneous lesions and associated pruritus. Scleromyxedema is an idiopathic cutaneous mucinosis that affects middle-aged adults. Patients present with a symmetrical distribution of 2-3 mm waxy or lichenoid papules coalescing to form thick plaques with sclerodermoid changes. These patients also have concurrent IgG monoclonal gammopathy and elevated lambda light chains, but the role of this gammopathy remains a debate. While these patients do have evidence of plasma cell dyscrasia, serum levels of these proteins do not correlate with disease progression or severity. In actuality, only 10% of these patients progress to develop frank multiple myeloma. Patients with scleromyxedema can develop internal manifestations, involving a number of systems such as neurologic, rheumatologic, muscular, cardiac, respiratory, and renal organs. Treatment for this condition is disappointing, because multiple agents have been tried with limited success. Main treatments include agents such as melphalan, systemic steroids, intravenous immunoglobulins (IVIGs), plasmapheresis, and various other chemotherapies.