What is the management and dosage for hyperparathyroidism?

Management of Hyperparathyroidism

Surgical excision of abnormal parathyroid tissue is the only definitive cure for primary hyperparathyroidism, with minimally invasive parathyroidectomy (MIP) being the preferred approach for single adenomas and bilateral neck exploration (BNE) for suspected multigland disease. 1

Types of Hyperparathyroidism and Initial Management

Primary Hyperparathyroidism

• Surgical management is indicated for all symptomatic patients and should be considered for most asymptomatic patients as it is more cost-effective than observation or pharmacologic therapy 2
• Indications for parathyroidectomy include:
  • Presence of symptoms
  • Age ≤50 years
  • Serum calcium >1 mg/dL above upper limit of normal
  • Osteoporosis
  • Creatinine clearance <60 mL/min/1.73m²
  • Nephrolithiasis or nephrocalcinosis
  • Hypercalciuria 3

Secondary Hyperparathyroidism

• Initial treatment includes:
  • Dietary phosphate restriction
  • Phosphate binders
  • Correction of hypocalcemia
  • Vitamin D supplementation (target 25-OH vitamin D levels >20 ng/mL) 1, 4
• For CKD-related secondary hyperparathyroidism:
  • Control serum phosphorus through dietary restriction and phosphate binders
  • Target serum phosphorus within normal range 4

Surgical Approaches

Primary Hyperparathyroidism

• Two main surgical options:
  • Minimally invasive parathyroidectomy (MIP) - preferred for single adenomas with positive preoperative imaging
  • Bilateral neck exploration (BNE) - gold standard, especially for suspected multigland disease or nonlocalizing imaging 5, 6
• Preoperative imaging with ultrasound and/or dual-phase 99mTc-sestamibi scintigraphy with SPECT/CT is recommended for localization 1
• Intraoperative parathyroid hormone monitoring is recommended for MIP to confirm successful removal 2

Secondary/Tertiary Hyperparathyroidism

• Surgical options include:
  • Subtotal parathyroidectomy
  • Total parathyroidectomy with autotransplantation
  • Total parathyroidectomy without autotransplantation 7, 4
• Total parathyroidectomy may be superior to total parathyroidectomy with autotransplantation regarding recurrent secondary hyperparathyroidism 4

Medical Management

Primary Hyperparathyroidism

• For patients who are not surgical candidates:
  • Ensure adequate calcium intake
  • Vitamin D supplementation for deficiency
  • Increase fluid intake to achieve urine volume of at least 2.5 liters daily for those with renal stones 1
• Bisphosphonates may be considered for bone protection 8

Secondary Hyperparathyroidism

• Vitamin D therapy:
  • Intermittent intravenous calcitriol or paricalcitol for hemodialysis patients (more effective than oral administration) 4
  • Adjust vitamin D sterol dosage according to severity of hyperparathyroidism 4
• Calcimimetics (Cinacalcet):
  • For persistent secondary hyperparathyroidism despite vitamin D therapy 4
  • Starting dose: 30 mg once daily
  • Titrate dose every 2-4 weeks through sequential doses of 30,60,90,120, and 180 mg once daily
  • Measure iPTH levels no earlier than 12 hours after most recent dose 9

Post-Treatment Monitoring

Post-Surgical Care

• Monitor ionized calcium every 4-6 hours for the first 48-72 hours after surgery, then twice daily until stable 1, 7
• Initiate calcium gluconate infusion if calcium levels fall below normal 1, 7
• Provide oral calcium carbonate and calcitriol when oral intake is possible 7

Medical Management Monitoring

• For patients on cinacalcet:
  • Monitor serum calcium approximately monthly for patients with secondary HPT
  • Monitor serum calcium every 2 months for patients with primary HPT 9
• For vitamin D therapy:
  • Reduce or temporarily discontinue if serum calcium rises above normal range 4

Common Pitfalls and Caveats

• Preoperative parathyroid biopsy should be avoided 2
• Devascularized normal parathyroid tissue should be autotransplanted during surgery 2
• Do not delay surgical intervention in patients with recurrent renal stones and hyperparathyroidism, as this can lead to progressive renal damage 1
• Cinacalcet tablets should always be taken whole and not divided, and should be taken with food or shortly after a meal 9
• Surgeons who perform a high volume of parathyroidectomies have better outcomes 2