Hypercalcemic Encephalopathy as the Initial Presentation of Primary Hyperparathyroidism in the Elderly

Abstract

Primary hyperparathyroidism (pHPT) refers to the parathyroid gland's unregulated excess parathyroid hormone production, leading to calcium metabolism impairment. Parathyroid adenomas are the leading cause of pHPT, which the sestamibi scintigraphy can detect with 95% sensitivity. While pHPT has diverse presentations, osteoporosis and asymptomatic vertebral fractures are the most common. Here we present a case of a 70-year-old female with worsening delirium secondary to pHPT, which the sestamibi scan did not pick up.