Parathyroidectomy in Dialysis Patients with Secondary Hyperparathyroidism: Long-Term Biochemical Outcomes and Preoperative Imaging Performance

Background/Objectives: Secondary hyperparathyroidism (SHPT) is a major chronic kidney disease complication requiring parathyroidectomy in medically refractory cases. Limited data exist on imaging performance and metabolic outcomes, particularly uric acid metabolism, following parathyroidectomy in dialysis patients. Methods: This retrospective cohort study included 68 hemodialysis patients undergoing parathyroidectomy for SHPT. Biochemical parameters including iPTH, calcium, phosphorus, alkaline phosphatase, uric acid, hemoglobin, and erythropoiesis-stimulating agent doses were measured preoperatively and up to 36 months postoperatively. We evaluated the diagnostic accuracy of preoperative ultrasonography and dual-phase 123I/99mTc sestamibi scintigraphy for parathyroid localization. Surgical techniques included subtotal parathyroidectomy (70.6%) and total parathyroidectomy (29.4%). Results: Parathyroidectomy resulted in dramatic iPTH reductions at 12 months (p < 0.001). Hungry bone syndrome occurred in 89.7% of patients. Notably, uric acid levels showed no significant change (p = 0.280), while hemoglobin improved and erythropoiesis-stimulating agent requirements decreased. Ultrasonography demonstrated 45.5% sensitivity with 98.0% positive predictive value, while scintigraphy achieved 55.0% sensitivity with 99.2% positive predictive value. Combined imaging improved sensitivity to 60.0% while maintaining 97.8% positive predictive value. Concurrent thyroid pathology was identified in nine patients (13.2%), including multinodular goiter in seven patients (10.3%) and papillary thyroid carcinoma in two patients (2.9%). Conclusions: Parathyroidectomy effectively treats refractory SHPT with sustained biochemical control, and combined imaging provides complementary preoperative information. Unlike primary hyperparathyroidism, no detectable change in uric acid levels was observed after parathyroidectomy in dialysis patients; given the limited statistical power, this finding is hypothesis-generating and suggests that hyperuricemia in this population may require independent management.