Hungry bone syndrome after parathyroid surgery

INTRODUCTION: Data on the incidence rates of hungry bone syndrome after parathyroidectomy in patients on dialysis are inconsistent, as the published rates vary from 15.8% to 92.9%.

METHODS: Between 2009 and 2019, 120 hemodialysis patients underwent parathyroidectomy for secondary hyperparathyroidism at the Chang Gung Memorial Hospital. The patients were stratified into two groups based on the presence (n = 100) or absence (n = 20) of hungry bone syndrome after parathyroidectomy.

FINDINGS: Subtotal parathyroidectomy was the most common surgery performed (76.7%), followed by total parathyroidectomy with autoimplantation (23.3%). Pathological examination revealed parathyroid hyperplasia. Hungry bone syndrome developed within 0.3 ± 0.3 months and lasted for 11.1 ± 14.7 months. After surgery, compared with patients without hungry bone syndrome, patients with hungry bone syndrome had lower levels of nadir corrected calcium (P < 0.001), as well as lower nadir (P < 0.001) and peak (P < 0.001) intact parathyroid hormone levels. During 59.3 ± 44.0 months of follow-up, persistence and recurrence of hyperparathyroidism occurred in 25 (20.8%) and 30 (25.0%) patients, respectively. Furthermore, patients with hungry bone syndrome had a lower rate of persistent hyperparathyroidism than those without hungry bone syndrome (P < 0.001). Four patients (3.3%) underwent a second parathyroidectomy. Patients with hungry bone syndrome received fewer second parathyroidectomies than those without hungry bone syndrome (P < 0.001). Finally, a multivariate logistic regression model revealed that the preoperative blood ferritin level was a negative predictor of the development of hungry bone syndrome (P = 0.038).

DISCUSSION: Hungry bone syndrome is common (83.3%) after parathyroidectomy for secondary hyperparathyroidism in patients undergoing hemodialysis, and this complication should be monitored and managed appropriately.