Diagnosis of Graves' Disease and Methimazole-Induced Lupus Erythematosus in an Adolescent Male During the COVID-19 Era: A Case Report.

Graves' disease is the most common form of hyperthyroidism in the pediatric population. Methimazole is the recommended regimen that is well-tolerated in most patients. Treatment with methimazole leading to drug-induced lupus erythematosus (DILE) is not well reported in the pediatric population, especially in the COVID-19 era. We present a case of a 14-year-old Caucasian male who presented with concerns of long COVID due to shortness of breath, hypertension, and fatigue. He was not noted to have significant weight loss, exophthalmos, or sleeping difficulties. He was followed by his general pediatrician, pediatric endocrinologist, cardiologist, and rheumatologist. Laboratory tests confirmed the diagnosis of Graves' disease, and treatment was initiated with methimazole and atenolol. One month into treatment, the patient developed polyarthritis, urticarial rash, and difficulty with gait. Based on clinical suspicion and antibody panels, he was diagnosed with DILE secondary to treatment with methimazole. The patient was then started on a potassium iodide (Lugol) solution to promote the euthyroid state and proceed with total thyroidectomy. Post surgery, the patient developed hypothyroidism, which was managed with oral levothyroxine, to which the patient responded well. By discussing the clinical presentation and treatment of this patient, the goal is to raise awareness and increase clinical suspicion in diagnosing Graves' and DILE in adolescents with upper respiratory presentations.