Is Graves' Dermopathy a Generalized Disorder?

The pathogenesis of the extrathyroidal manifestations of Graves' disease—ophthalmopathy and pretibial myxedema (Graves' dermopathy)—involves fibroblast activation and increased mucin (glycosaminoglycan) production. It is unclear why fibroblasts are activated at these sites and evidence for site-specific and generalized fibroblast activation is conflicting. One previous report has demonstrated an increase in glycosaminoglycan deposition in the forearm skin of patients with Graves' disease but without pretibial myxedema. We have sought to confirm the existence of subclinical dermopathy in the forearm tissue from patients with untreated (UG) and treated (TG) Graves' disease and compared the histological changes with normal controls (C), treated toxic nodular goiter (MNG) and Graves' dermopathy specimens (PTM), using stains for mucin, elastin, glycosaminoglycans (GAGs), and HLA-DR molecules. Four of 4 PTM specimens stained positive for mucin, with varying sparse, fragmented, or dense elastin fibers. Four of 5...