Treatment of Hyperparathyroidism
Parathyroidectomy is the only curative treatment for primary hyperparathyroidism and should be performed in all symptomatic patients and most asymptomatic patients, while secondary hyperparathyroidism requires initial medical management with dietary phosphate restriction, phosphate binders, and vitamin D sterols, reserving surgery for severe refractory cases. 1, 2
Primary Hyperparathyroidism
Surgical Indications
Surgery is indicated for: 2, 3
- All symptomatic patients (kidney stones, bone pain, fractures, neuromuscular symptoms) 2
- Asymptomatic patients meeting any of these criteria: 2, 3
- Age ≤50 years
- Serum calcium >1 mg/dL above upper limit of normal
- GFR <60 mL/min/1.73 m²
- Osteoporosis on DEXA scan
- Hypercalciuria
- Nephrolithiasis or nephrocalcinosis
Surgical Approach Selection
Minimally invasive parathyroidectomy (MIP) is preferred when a single adenoma is confidently localized preoperatively, offering shorter operating times, faster recovery, and lower costs compared to bilateral neck exploration. 1, 2
- Confident preoperative localization of single parathyroid adenoma
- Intraoperative PTH monitoring to confirm removal
- Appropriate for approximately 80% of patients
Bilateral neck exploration (BNE) is necessary for: 1, 4
- Discordant or nonlocalizing preoperative imaging
- Suspected multigland disease
- Patients with PTH ≤50 pg/mL (58.9% have multigland disease)
Preoperative Imaging
Sestamibi (99Tc-Sestamibi) scan has the highest sensitivity for localizing parathyroid adenomas. 2 Additional imaging options include ultrasound, CT scan, or MRI, particularly for reoperative cases. 1
Common pitfall: Avoid preoperative parathyroid biopsy, as it is not recommended. 5
Secondary Hyperparathyroidism
Initial Medical Management
Start with this stepwise approach for CKD patients on dialysis: 1, 2
- Dietary phosphate restriction 1
- Phosphate binders 1
- Correction of hypocalcemia with calcium supplementation 2
- Vitamin D sterols (calcitriol, paricalcitol, doxercalciferol) with dosage adjusted to severity 1, 2
Dosing for peritoneal dialysis patients: 1
- Calcitriol: 0.5-1.0 μg orally 2-3 times weekly
- Doxercalciferol: 2.5-5.0 μg orally 2-3 times weekly
Monitoring During Medical Treatment
Strict monitoring schedule: 1, 2
- Serum calcium and phosphorus: Every 2 weeks for 1 month after initiation or dose increase, then monthly
- PTH: Monthly for at least 3 months, then every 3 months once target levels achieved
Calcimimetics (Cinacalcet)
For persistent secondary hyperparathyroidism despite initial therapy, cinacalcet may be considered. 1, 2, 6
Dosing: Start at 30 mg once daily, titrate no more frequently than every 2-4 weeks to target iPTH levels of 150-300 pg/mL 2
Critical caution: Monitor closely for hypocalcemia and increased QT interval. 1, 2
FDA indication: Cinacalcet is indicated for secondary hyperparathyroidism in adult CKD patients on dialysis, but NOT for CKD patients not on dialysis due to increased hypocalcemia risk. 6
Surgical Indications for Secondary Hyperparathyroidism
Parathyroidectomy is recommended for severe hyperparathyroidism with: 1
- Persistent iPTH >800 pg/mL
- Associated hypercalcemia and/or hyperphosphatemia
- Refractory to medical therapy
Surgical options: 1
- Subtotal parathyroidectomy
- Total parathyroidectomy with parathyroid tissue autotransplantation
- Total parathyroidectomy
Critical caveat: Total parathyroidectomy is NOT recommended for patients who may subsequently receive a kidney transplant, as calcium control becomes problematic. 1
Postoperative Management
Monitor ionized calcium: 1
- Every 4-6 hours for first 48-72 hours
- Twice daily until stable
- Initiate calcium gluconate infusion as needed
- Adjust phosphate binders based on serum phosphorus levels
Devascularized normal parathyroid tissue should be autotransplanted during surgery. 5
Primary Hyperparathyroidism in Non-Surgical Candidates
For patients unable to undergo parathyroidectomy, cinacalcet is FDA-approved for treating hypercalcemia in primary hyperparathyroidism when surgery would be indicated based on calcium levels but cannot be performed. 6