Pretibial myxedema in a euthyroid patient.

Pretibial myxedema (PM) is a rare extrathyroidal manifestation of Graves' disease (GD), usually during the hyperthyroid state, coexisting with orbitopathy. We describe a rare case of a biopsy-proven PM in a euthyroid patient, without history of GD or Hashimoto's thyroiditis. Assessment of commonly reported thyroid autoantibodies, such as thyroid peroxidase and thyroglobulin autoantibodies, thyroid stimulating immunoglobulins and thyroid binding inhibitory immunoglobulins, was negative.