Factors Predicting the Need for Intravenous Calcium Infusion in Patients With Advanced Primary Hyperparathyroidism Undergoing Parathyroidectomy.

BACKGROUND: A substantial proportion of patients with primary hyperparathyroidism (PHPT) presenting with advanced skeletal manifestations develop "hungry bone syndrome" following parathyroidectomy (PTx). This study aimed to identify predictors of the need for intravenous (IV) calcium (Ca) infusion in the postoperative period. METHODS: This retrospective study (January 2000-December 2024) included 554 symptomatic PHPT patients undergoing PTx. Patients were divided into two groups: Group 1 (n = 96), who required IV Ca infusion, and Group 2 (n = 458), who did not. Clinical, biochemical, and operative parameters were compared. RESULTS: Overall, 17% of patients required IV Ca infusion. On univariate analysis, Group 1 patients were significantly young (p < 0.001) and had a higher incidence of bed-ridden status (p = 0.001), bony symptoms (p < 0.001), skeletal fractures (p < 0.001), and osteoporosis (p = 0.025). Serum parathyroid hormone (PTH; p = 0.001) and alkaline phosphatase levels (p < 0.001) were significantly higher, whereas bone mineral density at the spine (p = 0.001), hip (p < 0.001), and distal radius (p = 0.001) was significantly lower. Bilateral neck exploration (BNE; p = 0.047) as well as resected gland size (p < 0.001) and weight (p = 0.007) were higher in Group 1. On multivariable analysis, age (p = 0.006), bony symptoms (p = 0.016), PTH (p = 0.041), BNE (p = 0.014), and parathyroid weight (p = 0.005) remained significant predictors. CONCLUSIONS: Young age, bony symptoms, BNE, and higher PTH levels and gland weight are significant predictors of the need for IV Ca after PTx in advanced PHPT. However, most patients can be effectively managed with oral Ca and vitamin D supplementation.