Livedo reticularis: a rare manifestation of Graves hyperthyroidism associated with anticardiolipin antibodies.

Livedo reticularis is a common presentation of the anticardiolipin syndrome. Although the presence of anticardiolipin (aCL) antibodies was previously reported in association with both Graves disease and Hashimoto thyroiditis, I am aware of no previous report of livedo reticularis in patients with Graves disease. A 29-year-old woman presented with very active Graves thyrotoxicosis. Physical examination revealed, in addition to signs of very active hyperthyroidism, marked livedo reticularis on both her legs. Laboratory tests confirmed the clinical impression regarding her thyroid activity and revealed prolonged prothrombin time (and partial thromboplastin time) and elevated levels of both immunoglobulin G and immunoglobulin M aCL antibodies. After methimazole-induced remission, livedo reticularis completely disappeared and the levels of aCL antibodies decreased to within the low range of normal. The literature on aCL antibodies and autoimmune thyroid diseases is reviewed and the interaction between the occurrence of aCL antibodies, disease activity, and drug therapy in Graves disease is discussed.