Thionamides are drugs frequently used for the treatment of hyperthyroidism in Basedow-Graves' disease (BGD), both as primary therapy and for the preparation of patients undergoing surgery or radioiodine therapy. Adverse reactions related to these drugs affect 3-12% of patients, varying from minor and transient reactions, more frequently, to uncommon, severe and potentially fatal ones. We describe a patient diagnosed with hyperthyroidism due to BGD, who developed polyarthralgia followed by ulcer-necrotizing cutaneous lesions in the distal extremities of the legs, after use of methimazole for about a month, with laboratory and histologic evaluation compatible with cutaneous leukocytoclastic vasculitis, a pattern found in hypersensitivity vasculitis. After withdrawal of the anti-thyroid drug and following prednisone treatment, patient’s skin lesions improved, with radioiodine therapy being performed thereafter.
Cutaneous vasculitis; Methimazole; Adverse reactions; Anti-thyroid drugs; Hyperthyroidism
