Dermopathy of Graves disease (pretibial myxedema). Review of 150 cases.

Pretibial myxedema is an uncommon manifestation of Graves disease, and little information is available regarding its natural course and its relation to other manifestations of Graves disease. We reviewed 150 consecutive cases with the diagnosis of pretibial myxedema over a 20-year period in a referral center. Only 1 patient in this group did not have ophthalmopathy, whereas 88% had significant proptosis and 30% required orbital decompression surgery. Dermopathy was a late manifestation of Graves disease, and its onset usually followed the diagnosis of hyperthyroidism and ophthalmopathy. In a few patients, dermopathy preceded diagnosis of hyperthyroidism or onset of ophthalmopathy. Fourteen patients were never clinically hyperthyroid; spontaneous hypothyroidism had developed in 11 in this group. All cases involved the lower extremities, with only 1 patient having combined upper and lower extremity involvement. The most common form of thyroid dermopathy was nonpitting edema, followed by nodular and plaque forms, which occurred with equal frequency. The polypoid form occurred in 1 patient and the elephantiasic form in another; 7.3% had thyroid acropachy. Follow-up was available for 120 patients (range, 3 mo to 19 yr; mean, 3.2 yr), and complete remission was observed in only 12 patients. Topically applied corticosteroid therapy was used in 76 patients, and in this group 38% had sustained long-term partial remission, as opposed to 18% in the group receiving no corticosteroid therapy.