What is the best course of action for hyperparathyroidism due to an abnormal right inferior parathyroid gland?

Management of Hyperparathyroidism Due to Right Inferior Parathyroid Gland Abnormality

Surgical parathyroidectomy is the recommended treatment for hyperparathyroidism with a PTH level of 116 pg/mL from an abnormal right inferior parathyroid gland. 1

Diagnostic Confirmation

Before proceeding with surgery, confirm the diagnosis with:

• Serum calcium levels (to determine if hypercalcemic)
• Phosphate levels
• Vitamin D status
• Imaging to localize the abnormal gland:
  • 99mTc-sestamibi scan (highest sensitivity)
  • Ultrasound of the neck
  • Consider 4D-CT for precise localization if planning minimally invasive approach

Surgical Approach

The two main surgical options are:

1. Minimally Invasive Parathyroidectomy (MIP):

   • Preferred for single adenoma cases
   • Requires confident preoperative localization
   • Benefits: shorter operating time, faster recovery, decreased costs 1
   • Use intraoperative PTH (IOPTH) monitoring to confirm complete removal 2
   • IOPTH should decrease >50% from baseline and return to normal range 3

2. Bilateral Neck Exploration:

   • Consider if imaging is discordant or non-localizing
   • Necessary when multiglandular disease is suspected 1

Postoperative Management

After parathyroidectomy:

• Monitor ionized calcium every 4-6 hours for first 48-72 hours, then twice daily until stable 1
• If calcium drops below normal (<0.9 mmol/L or <3.6 mg/dL):
  • Start calcium gluconate infusion (1-2 mg elemental calcium per kg body weight per hour) 1
  • Gradually reduce infusion when calcium levels stabilize 1
• When oral intake is possible, provide:
  • Calcium carbonate 1-2g three times daily
  • Calcitriol up to 2μg/day 1
• Adjust phosphate binders based on serum phosphorus levels 1

Special Considerations

• Multiglandular disease: IOPTH monitoring is crucial to detect possible double adenomas that may not be identified preoperatively 2
• Recurrence risk: Complete removal of all abnormal tissue is essential to prevent recurrence
• Imaging limitations: Ultrasound and sestamibi have 70-80% sensitivity for single adenomas but much lower sensitivity for multiglandular disease 3

Pitfalls to Avoid

1. Missing multiglandular disease: Rely on IOPTH monitoring to confirm adequate resection
2. Inadequate preoperative localization: Use multiple imaging modalities when results are discordant
3. Incomplete follow-up: Monitor calcium and PTH levels postoperatively to ensure cure
4. Overlooking ectopic glands: Be aware that parathyroid glands can be located in unusual positions, including behind the cricoid cartilage 4

By following this approach, successful treatment of hyperparathyroidism can be achieved with minimal complications and low recurrence rates.