A 31-year-old man with a history of renal failure, joint pain, weakness, and persistently elevated serum calcium recently underwent a 3.5-gland parathyroidectomy followed by a neck reexploration and retrieval of the remaining para-thyroid for persistent hypercalcemia.

Ninety percent of patients with hypercalcemia have either primary hyperparathy-roidism or malignancy. Primary hyperparathyroidism may be due to solitary adenomas or multiple endocrine neoplasia. In the case of malignancy, hypercalcemia is a serum abnormality found during the clinical evaluation for the patient’s symptoms associated with the malignancy. These symptoms may include weight loss, fatigue, and night sweats. Malignancies that may cause hypercalcemia include metastatic breast cancer and solid tumors such as lung and renal cancers. Additionally, hematologic malignancies, such as lymphoma, leukemia, and multiple myeloma, may also cause hypercalcemia.

Less common causes for hypercalcemia include vitamin D intoxication, idiopathic hypercalcemia of infancy, hyperthyroidism, thiazide diuretics, and vitamin A intoxication. When associated with renal failure, etiologies for hypercalcemia include severe secondary hyperparathyroidism, aluminum intoxication, and milk-alkali syndrome.