Hypercalcemia

About Hypercalcemia

Hypercalcemia is an elevated serum calcium level above 10.5 mg dL 2.6 mmol L with normal albumin, or corrected calcium. Severe hypercalcemia above 14 mg dL is a medical emergency. The two most common causes are primary hyperparathyroidism, most common in people outside hospital, and malignancy, most common in hospitalized patients. Hyperparathyroidism is usually caused by a single parathyroid adenoma. Malignancy associated hypercalcemia occurs through parathyroid hormone related peptide PTHrP production squamous cell cancers, breast cancer, or direct bone destruction multiple myeloma, metastatic cancer. Other causes include thiazide diuretics, vitamin D intoxication, sarcoidosis and other granulomatous diseases, immobilization in young growing patients or Paget disease, hyperthyroidism, and milk alkali syndrome excessive calcium and antacid intake. Symptoms, often remembered by the mnemonic stones, bones, abdominal groans, and psychic moans, include kidney stones nephrolithiasis from hypercalciuria, bone pain and osteoporosis from increased bone resorption, abdominal pain, nausea, constipation, and peptic ulcers from calcium stimulated gastrin, and psychiatric symptoms depression, confusion, anxiety, fatigue, and in severe cases coma. Severe hypercalcemia causes shortened QT interval on ECG. Severe hypercalcemia is treated in hospital, starting with intravenous isotonic saline to promote renal calcium excretion. Bisphosphonates zoledronic acid, pamidronate inhibit osteoclast activity but need 2 to 4 days for full effect. Calcitonin provides faster but temporary reduction. Denosumab is an alternative for malignancy associated hypercalcemia. Glucocorticoids work for granulomatous and vitamin D mediated hypercalcemia. Dialysis removes calcium in renal failure. Definitive treatment of hyperparathyroidism is parathyroidectomy.