Abstract: PO0365
A Rare Case of Hyperthyroidism Presenting with Symptomatic Hypercalcemia
Session Information
- Biochemical Aspects of Mineral and Bone Disease
October 22, 2020 | Location: On-Demand
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Report
- 402 Bone and Mineral Metabolism: Clinical
Authors
- Lodhi, Sameed Khalid, Carle Foundation, Urbana, Illinois, United States
- Jasti, Sravan, Carle Foundation, Urbana, Illinois, United States
- Ghazanfar, Hareem, King Edward Medical University, Lahore, Pakistan
Introduction
Primary hyperparathyroidism and hypercalcemia are by far the most common causes of hypercalcemia in clinical practice. Asymptomatic hypercalcemia with minimally raise calcium levels have been documented in 20% of cases of hyperthyroidism as well and is related to increased bone resorption by osteoclasts and subsequent release of calcium into circulation. We describe a rare case of hyperthyroidism with symptomatic hypercalcemia as the first clinical manifestation.
Case Description
A 60 year old male with a history significant for chronic kidney disease, stroke and hypertension was admitted to the hospital following a syncopal event. Physical examination and baseline investigations were normal other than elevated calcium levels of 12.1 mg/dl. PTH levels and PTHrP levels were normal ruling out hyperparathyroidism and paraneoplastic related hypercalcemia. Vitamin D levels were also found to be normal. Workup for multiple myeloma was negative. Thyroid panel was done which showed extremely low levels of TSH (<0.005 mIU/L) with elevated T3 and T4 levels (12.9 ng/dL and 5.52 ng/dL respectively). Thyroid scan was performed which showed significant thyroiditis. Thyrotropin receptor antibody test also came positive. The patient was diagnosed with Graves’ disease based on the laboratory investigations and subsequently started on 5 mg methimazole TID. He also received one dose of zolendronic acid in the hospital. His calcium levels stabilized, falling from 12.4 to 9-10 mg/dL within 1 month. Patient received methimazole for a total of 7 months after which it was discontinued as his TSH levels (1.38 mIU/mL), T3 levels (2.19 ng/dL) and T4 (0.78ng/dL) normalized. Patient further underwent radioiodine ablation for the treatment of Graves’ disease.
Discussion
In past, multiple cases have been reported of concurrent hyperparathyroidism or vitamin D deficiency in hyperthyroid patients. This case is unique as the patient presented with symptomatic hypercalcemia in the absence of other causes and in the absence of other more common symptoms of hyperthyroidism. To our knowledge, only 2 cases of hyperthyroidism have been reported previously with hypercalcemia as the first clinical manifestation. Clinicians should be aware of association of hypercalcemia with hyperthyroidism as it will facilitate early diagnosis and appropriate intervention.