What is the most appropriate next step in management for a patient with symptomatic primary hyperparathyroidism (fatigue, recurrent ureteric stones, bone pain), serum calcium 3.5 mmol/L, phosphate 0.6 mmol/L, parathyroid hormone 6.5 pmol/L, and a 2‑cm parathyroid adenoma?

Parathyroidectomy is the Most Appropriate Next Step

This patient requires urgent parathyroidectomy—surgery is the only definitive curative treatment for symptomatic primary hyperparathyroidism with documented target-organ damage (recurrent kidney stones, bone pain) and a confirmed 2-cm parathyroid adenoma. 1, 2

Why Surgery is Indicated Now

This patient meets multiple absolute indications for immediate surgical intervention:

• Symptomatic disease with target-organ involvement: Recurrent ureteric stones and bone pain represent clear end-organ damage from prolonged hypercalcemia 1, 2
• Severe hypercalcemia: Calcium of 3.5 mmol/L (approximately 14 mg/dL) is more than 0.25 mmol/L above the upper limit of normal, indicating severe disease 3
• Confirmed anatomic source: The 2-cm parathyroid adenoma identified on imaging confirms the source of autonomous PTH overproduction and enables minimally invasive surgical planning 1, 2
• Biochemical confirmation: Elevated PTH (6.5 pmol/L) with hypercalcemia and low phosphate (0.6 mmol/L) definitively confirms primary hyperparathyroidism 3

Delaying surgery for medical management is not recommended when patients have symptomatic disease with clear target-organ damage. 1, 2

Why the Other Options Are Incorrect

A. Bisphosphonates – Temporizing Only, Not Definitive

• Bisphosphonates serve only as temporizing agents for acute hypercalcemia management and do not address the underlying autonomous PTH secretion 2
• They may be used acutely to lower calcium before surgery but are not a substitute for definitive treatment 3

B. Calcimimetics – Not Standard for Primary HPT

• Calcimimetics are not mentioned in guidelines as standard therapy for primary hyperparathyroidism due to parathyroid adenoma
• They do not remove the source of disease and would leave the patient with ongoing target-organ damage

C. Increased Calcium Diet – Absolutely Contraindicated

• Increasing calcium intake is completely contraindicated in hypercalcemia, as it would worsen the patient's already dangerously elevated calcium levels 1, 2
• Dietary recommendations for primary hyperparathyroidism call for normal calcium intake (1000-1200 mg/day), not restriction or supplementation 3

Surgical Approach and Planning

Preoperative Localization

• The identified 2-cm adenoma enables minimally invasive parathyroidectomy (MIP) rather than bilateral neck exploration 1, 2
• Preoperative imaging with sestamibi scan and/or ultrasound facilitates accurate localization for focused surgery 1

Intraoperative Monitoring

• Intraoperative PTH monitoring should be employed to confirm complete excision of the hyperfunctioning tissue 2, 4
• A drop in PTH of >50% from baseline within 10-15 minutes confirms successful removal 4

Surgeon Selection

• Referral to a high-volume, experienced parathyroid surgeon is critical—surgeons performing >100 thyroid/parathyroid procedures annually have 4 times fewer complications than low-volume surgeons 5, 1

Critical Postoperative Management

Hungry Bone Syndrome Monitoring

This patient is at high risk for hungry bone syndrome given:

• Severe preoperative hypercalcemia (3.5 mmol/L)
• Bone pain indicating significant bone demineralization
• Large adenoma (2 cm) suggesting prolonged disease

Mandatory postoperative protocol:

• Monitor ionized calcium every 4-6 hours for the first 48-72 hours 1, 2
• If ionized calcium falls below 0.9 mmol/L, immediately start calcium gluconate infusion at 1-2 mg elemental calcium/kg/hour 1, 2
• Transition to oral calcium carbonate 1-2 g three times daily plus calcitriol up to 2 µg/day once oral intake is tolerated 1, 2

Common Pitfall to Avoid

Do not wait for calcium to become symptomatic before treating—proactive replacement based on laboratory values prevents tetany and seizures in the setting of rapid bone remineralization 1

Expected Outcomes

• Cure rate exceeds 95% with experienced surgeons for single adenoma 6, 4
• Resolution of bone pain and prevention of further kidney stones 1
• Normalization of calcium and PTH within hours to days 7
• Improvement in quality of life and prevention of long-term complications of hypercalcemia 1

The answer is D. Parathyroidectomy.