Hypercalcemic crisis in the era of targeted parathyroidectomy

Hypercalcemic crisis patients are appropriately treated by expeditious parathyroidectomy. Previous studies have suggested that crisis patients may have lower operative success rates compared to non-crisis patients. This study reviews the outcomes for hypercalcemic crisis in the era of targeted parathyroid surgery.

The records of 839 patients with primary hyperparathyroidism who underwent parathyroidectomy at a single institution from 1993 to 2009 were reviewed. From this group, 34 patients were surgically treated for hypercalcemic crisis, defined as having signs and symptoms of acute calcium intoxication and serum calcium levels≥14 mg/dL. All patients underwent parathyroidectomy guided by preoperative localization studies and intra-operative PTH hormone monitoring (IPM). Pre- and postoperative symptoms and laboratory values and rates of operative failure and recurrence were compared to 805 patients without crisis.

Mean preoperative serum calcium (15.8 versus 11.6 mg/dL) and parathyroid hormone (PTH) (719 versus 175 pg/mL) levels were significantly higher among patients presenting with hypercalcemic crisis (P<0.0001). Postoperatively, the mean calcium and PTH levels were similar (9.4 versus 9.4 mg/dL, P=0.7) and (82 versus 51 pg/mL, P=0.1), respectively. Alteration in mental status as a presenting symptom was significantly more prevalent among those in crisis (24% versus 3%, P<0.0001), as was pancreatitis (6% versus 0.2%, P=0.001). The crisis patients were more likely to have an ectopic gland in the mediastinum (15 versus 2%, P<0.0001), significantly larger glands (2.4 versus 1.8 cm, P=0.001), and parathyroid carcinoma (6% versus 0.3%, P=0.015). Crisis patients had similar rates of operative success 34/34 (100%), compared with 787/805 (97.8%) non-crisis patients (P=0.9). There was no difference in recurrence rates (3% versus 1.4%, P=0.3). Mean overall follow-up was 36 mo.

Despite presenting with more ectopic glands and parathyroid cancer, crisis patients have similar parathyroidectomy success rates compared with non-crisis patients. The high rate of success in the era of targeted parathyroidectomy may be due to the widespread use of localization studies and IPM.