Abstract
Hypercalcemia (HC) is a common clinical problem. Among all causes of HC, primary hyperparathyroidism (HPT) and malignancy are the most common, accounting for >90 % of cases. We present a case of HC in a patient attributed to long-standing history of Sarcoidosis (SC) and later found to also have HPT with Parathyroid Adenoma (PA) and Vitamin D Deficiency.
A 64-year-old female presented to the emergency room for social needs. She had not received medical care for the past 10 years and had known history of SC, previously treated with prednisone and methotrexate. She also noted a long-standing history of elevated calcium (Ca) up to 11 mg/dL. She was fasting for the past 1 month for spiritual reasons and was not taking any medications or supplements. Initial labs were significant for Ca of 13.2 mg/dL, Albumin 4.4 g/dL, ionized Ca 1.43 mmol/L. Creatinine was 1.1. EKG revealed T-wave inversions in V1, 2, 3. She received IV fluids and Ca improved to 11 mg/dL. HC was attributed to known history of SC. However further evaluation revealed parathyroid hormone (PTH) level high at 156 pg/mL, 25-OH Vit D level low at 8.5 ng/mL with normal 1,25 hydroxy Vit D levels at 46 pg/mL. Parathyroid sestamibi scan revealed a left parathyroid adenoma. Surgery was deferred because patient was asymptomatic and did not meet criteria for parathyroidectomy. On discharge, Ca levels remained stable and she was started on Ergocalciferol 50,000 units weekly.
HC can be either parathyroid mediated, non-parathyroid mediated, or due to medications. In primary HPT, the elevated PTH levels cause increased bone resorption through activated osteoclasts and increased intestinal Ca absorption. Malignancies involving solid tumors and leukemias can lead to HC through osteolysis and osteoclasts or PTH-related peptide. Thiazide diuretics increase renal Ca absorption that lead to mild HC which can be reversed when the medication is discontinued. Other endocrine disorders that can lead to HC include thyrotoxicosis-induced bone resorption, adrenal insufficiency and pheochromocytoma.
Management of hypercalcemia depends upon the level of Ca. Mild HC (Ca < 12mg/dL) is usually asymptomatic and improves with hydration. Asymptomatic or mildly symptomatic patients with chronic moderate HC (Ca 12-14 mg/dL) may not require immediate treatment. Severe HC (Ca >14mg/dL) is treated with IV hydration with normal saline (NS), calcitonin and zolendronic acid. Administration of calcitonin and NS results in substantial reduction in Ca within 12-48 hours.
Although, HC was initially attributed to SC, primary HPT and low 25-OH Vit D levels also contributed to HC in this patient. Thus, it is important to evaluate patients with known HC from sarcoid for other etiologies.
Rare Case of Severe Hypercalcemia Secondary to Atypical Sestamibi Negative Parathyroid Cystic Adenoma