Indications for Surgery in Hyperparathyroidism
Primary Hyperparathyroidism
Surgery is indicated for all symptomatic patients with primary hyperparathyroidism and should be considered for most asymptomatic patients, as it is more cost-effective than observation or pharmacologic therapy. 1
Specific Surgical Indications
For asymptomatic patients, parathyroidectomy is indicated when any of the following criteria are met:
- Age ≤50 years 2
- Serum calcium >1 mg/dL above the upper limit of normal 2
- Creatinine clearance <60 mL/min/1.73 m² 2
- Presence of osteoporosis (by dual-energy x-ray absorptiometry) 1, 2
- Nephrolithiasis or nephrocalcinosis 2
- Hypercalciuria (>400 mg/24 hours) 2
Symptomatic Disease
Any patient with symptoms attributable to hypercalcemia or hyperparathyroidism should undergo surgery regardless of biochemical thresholds. 1 These symptoms include osteitis fibrosa cystica, kidney stones, or severe hypercalcemia requiring urgent intervention. 3
Quality of Life Considerations
While neuropsychological symptoms (fatigue, depression, cognitive impairment) are common in primary hyperparathyroidism, the evidence for improvement after surgery in truly asymptomatic patients is mixed. One study showed no significant improvement in neuropsychological symptoms in mild, incidentally detected cases 4, while another demonstrated significant improvement in mental health scores and reduction in depression and anxiety at 12 months postoperatively, particularly in patients with preoperative calcium levels >11.2 mg/dL (2.8 mmol/L). 5 This suggests that symptomatic patients with higher calcium levels benefit more from surgery in terms of quality of life outcomes.
Secondary Hyperparathyroidism (CKD-Related)
Parathyroidectomy should be recommended in patients with severe secondary hyperparathyroidism defined as persistent intact PTH >800 pg/mL (88.0 pmol/L) associated with hypercalcemia and/or hyperphosphatemia that are refractory to medical therapy. 6
Medical Therapy Must Fail First
Before considering surgery, patients must have failed adequate trials of: 6
- Dietary phosphate restriction
- Phosphate binders
- Correction of hypocalcemia
- Vitamin D sterols (calcitriol, paricalcitol, or doxercalciferol)
Additional Surgical Indication: Calciphylaxis
Parathyroidectomy is indicated for calciphylaxis with elevated PTH levels (>500 pg/mL or 55.0 pmol/L), as clinical improvement has been reported after surgery. 6 However, do not perform parathyroidectomy in calciphylaxis patients without documented hyperparathyroidism, as not all calciphylaxis cases have elevated PTH. 6
Critical Caveat for Transplant Candidates
Avoid total parathyroidectomy without autotransplantation in patients who may subsequently receive a kidney transplant, as postoperative calcium control becomes problematic. 6, 7 Subtotal parathyroidectomy or total parathyroidectomy with autotransplantation are preferred in this population. 6
Preoperative Preparation
Essential Workup Before Surgery
- Measure 25-hydroxyvitamin D and supplement if deficient 1
- Obtain 24-hour urine calcium measurement 1
- Perform dual-energy x-ray absorptiometry 1
- Measure serum calcium and intact PTH simultaneously to confirm diagnosis 8
Imaging Strategy
Preoperative localization imaging is essential for planning minimally invasive parathyroidectomy but is NOT required to establish the surgical indication. 8 The diagnosis of hyperparathyroidism is biochemical only. 8
Appropriate imaging modalities include: 8
- 99Tc-sestamibi scan
- Cervical ultrasonography
- 4-D parathyroid CT
- MRI
Patients with nonlocalizing or discordant imaging remain surgical candidates and should undergo bilateral neck exploration. 1
Reoperative Cases
For persistent or recurrent hyperparathyroidism, preoperative imaging with 99Tc-Sestamibi, ultrasound, CT, or MRI is mandatory prior to re-exploration. 6, 7 Reoperations have lower cure rates and higher complication rates than first-time surgery. 8
Common Pitfalls to Avoid
- Never use imaging to confirm or exclude the diagnosis of primary hyperparathyroidism—diagnosis is biochemical only. 8
- Never perform preoperative parathyroid biopsy. 1
- Be aware that PTH assays vary significantly between laboratories—use assay-specific reference values. 8
- Assess vitamin D status, as deficiency can complicate PTH interpretation and cause secondary hyperparathyroidism. 8
- In severe hypercalcemia with osteitis fibrosa cystica, consider normalizing calcium preoperatively with saline, calcitonin, and bisphosphonates, as this may reduce PTH levels, facilitate easier postoperative calcium management, and begin resolution of bone disease before surgery. 3