Abstract

Drug-Induced Lupus Erythematosus (DILE) is a rare drug-related reaction characterized by symptoms and laboratory findings similar to those of idiopathic lupus. We describe a case of DILE developed after methimazole administration. In this case, a man with a history of hyperthyroidism received methimazole for approximately two years. One year prior, he presented with a discoid rash, arthralgia, and intermittent fever. Routine laboratory examination revealed an elevated erythrocyte sedimentation rate and C-reactive protein levels, decreased complement levels, and abnormal autoantibodies. Histopathological examination revealed mucin staining, and the lupus band test was negative. The patient was diagnosed with DILE and treated with methylprednisolone and hydroxychloroquine after the immediate discontinuation of methimazole. In conclusion, this case report describes a distinctive discoid cutaneous lesion of methimazole-induced lupus erythematosus that is very rare in clinical practice. We hope that this will improve awareness of this disease in clinical practice.