Abstract
Primary aldosteronism (PA) is a rare disorder. The majority of patients with PA present with typical features and are easily diagnosed. This disorder is usually diagnosed with hypokalemia, hypertension or an adrenal mass. However, patients with atypical symptoms may present a challenge for diagnosis and treatment. In the present study, a case of PA is described that presented with hypokalemic myopathy simulating polymyositis. The patient was a 44-year-old woman who presented with weakness and difficulty walking. The patient was initially suspected to have PM and was treated with methylprednisolone. The patient was found to have hypokalemia which persisted despite high-dose supplementation of potassium. Adrenal computed tomography revealed a right adrenal mass. Surgical adrenalectomy was conducted. The final pathological diagnosis was benign adrenocortical adenoma. The serum tests remained normal and the patient's symptoms were resolved during the 8-month follow-up.