A 62-year-old woman with non-pitting leg oedema

A patient presented with non-pitting lymphoedema of the legs and finger clubbing. A skin biopsy showed epidermal hyperkeratosis and abundant mucinous material (Alcian blue positive) in reticular dermis. Treatment (radioactive iodine) for Grave's disease (with exophthalmus) 20 years ago, raised suspicion of thyroid dermopathy. Together, these three extrathyroidal manifestations of Graves' disease are typical of the EMO syndrome. In addition, the patient had elevated serum concentrations of thyroid-stimulating hormone receptor autoantibodies. Autoimmune mechanisms are involved in the stimulation of fibroblasts and the production of large amounts of mucin. Pretibial myxoedema relates to scars, mechanical factors, and dependent position. Lack of steroid treatment during radioactive iodine therapy and smoking, may have exacerbated the thyroid dermopathy in this case. Awareness of pretibial myxoedema as a late autoimmune manifestation of Graves' disease, may contribute to earlier diagnosis and correct treatment.