A 52-year-old woman comes to the office to discuss an elevated calcium level. Mild hypercalcemia was recently noted on a serum chemistry panel performed to manage her chronic antihypertensive therapy. The patient has no musculoskeletal symptoms other than occasional low back pain, and she walks 2-3 miles every day. She experienced menopause 2 years ago but has minimal vaginal dryness and no hot flashes. Current medications include lisinopril and a daily over-the-counter calcium and vitamin D supplement. Her mother suffered a hip fracture at age 60, and her father died of prostate cancer. The patient does not use tobacco, alcohol, or illicit drugs. Blood pressure is 144/91 mm Hg and pulse is 68/min. BMI is 25 kg/m². Physical examination is unremarkable. Laboratory results are as follows: Repeat serum calcium is 10.9 mg/dL and parathyroid hormone level is 89 pg/mL (normal: 10-65). X-rays of the thoracic and lumbar spine reveal no fractures. DXA reveals T-scores as follows: Which of the following is the most appropriate next step in management of this patient?

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11ec193a_97a0_d450_853d_5348d66e278e_MD0002_00 This patient has primary hyperparathyroidism (PHPT), which is characterized by persistent hypercalcemia with an elevated serum parathyroid hormone (PTH) level. Most patients are asymptomatic, and PHPT is diagnosed incidentally with elevated serum calcium levels on routine laboratory testing. However, patients with PHPT are at risk for long-term complications, including osteoporosis, nephrolithiasis, and chronic kidney disease. Definitive treatment for PHPT is surgical parathyroidectomy. Patients with symptomatic hypercalcemia or established complications of PHPT (eg, osteoporosis, chronic kidney disease) should be referred for surgery. Young patients (age <50) are likely to develop complications later in life and should also undergo parathyroidectomy. Other patients at elevated risk for complications include those with moderate to severe hypercalcemia (serum calcium >1 mg/dL above normal) or excessive urinary calcium loss (>400 mg/day). This patient has no confirmed complications of PHPT but should have a 24-hour urine calcium measurement to determine the need for parathyroidectomy. (Urine calcium measurement can also identify the occasional patient with familial hypocalciuric hypercalcemia, which also can cause PTH-dependent hypercalcemia.) (Choice B) Bisphosphonates increase bone density in PHPT, but there are no conclusive data on fracture prevention. They may be considered for PHPT patients with osteopenia who do not meet surgical criteria or who do not want to undergo parathyroidectomy. (Choices C and D) If this patient has urinary calcium excretion <400 mg/day, she does not require surgery but should be monitored with measurement of serum calcium and creatinine every year and DXA every 1-2 years. (Choice E) Localization of parathyroid adenoma with neck ultrasound, technetium-99m sestamibi, and/or 4-dimensional CT (which includes perfusion information) is typically performed if surgery is required. Educational objective: Indications for parathyroidectomy in primary hyperparathyroidism include age <50, symptomatic hypercalcemia, complications of hyperparathyroidism (osteoporosis, nephrolithiasis/calcinosis, chronic kidney disease), or elevated risk of complications (calcium >1 mg/dL above normal, urinary calcium excretion >400 mg/day). __________ References: Guidelines for the management of asymptomatic primary hyperparathyroidism: summary statement from the Fourth International Workshop. (http://www.ncbi.nlm.nih.gov/pubmed/25162665) Should 'mild primary hyperparathyroidism' be reclassified as 'insidious': is it time to reconsider? (http://www.ncbi.nlm.nih.gov/pubmed/21848908)

A 52-Year-Old Woman Comes to the Office to Discuss an Elevated