Hyperparathyroidism in a diabetic patient on dialysis

A 58-year-old male, who had type II diabetes and was on haemodialysis (HD) for 3 years, was referred for management of refractory hyperparathyroidism in 2006. In 2003, he started HD due to diabetic renal failure, after which vitamin D analogue together with oral calcium carbonate and sevelamer hydrochloride was administered, so that serum calcium and phosphate levels were controlled properly. Serum intact parathyroid hormone (iPTH) levels were <200 pg/dl. However, in 2006 serum calcium began to rise above 11 mg/dl and iPTH reached 400 pg/dl despite intravenous vitamin D administration. On admission, corrected calcium was 13.3 mg/dl, phosphate 6.2 mg/dl, alkaline phosphatase 1070 IU/l and iPTH 1640 pg/ml. 99mTc-methoxyisobutylisonitril (MIBI) scintigraphy revealed one enlarged functional parathyroid gland in the right lower region of the neck, which was shown as a irregularly enhanced nodule with calcification by a computed tomography (CT) scan (Figure 1a–c). Surgical parathyroidectomy (PTx) was performed and two parathyroid glands were removed. The right lower gland weighed 4000 mg and the other was almost normal without hyperplasia. Histology of the enlarged gland showed monotonous cellularity accompanied by all three typical