Endocrine Abstracts

A 50 years old man was seen in the Endocrine clinic with elevated calcium (2.80 mmol/l, normal 2.20-2.60) and Parathyroid hormone (10.7 pmol/l, normal 1.6-6.9) levels. His medical background includes Alport Syndrome, Renal Allografts (1st 1990, 2nd 2000 and 3rd 03/11/2005), and Osteopenia on DEXA scan in February 2020. He did not have any renal stones in the past. There was no family history of hypercalcemia. He was on Vitamin D 1000 Units daily (Vitamin D 55 nmol/l, normal 50-120), Lamotrigine, Aspirin, Azathioprine, Lansoprazole, Prednisolone, Tacrolimus, Losartan, Clonazepam and Paracetamol. He was noted to have raised calcium over 20 years and raised parathyroid hormone levels for few years. Even with the creatinine of 180 umol/l (59 – 104 umol/l) his calcium level was 2.7 mmol/. His 24 hours calcium/creatinine ratio was 0.0160 mmol/mmol when eGFR was 74 ml/min/1.73 m². Ultrasound of neck showed 7.2 x 6.6 x 3.1 mm lesion on posterior left lower lobe and avascular 4.7 mm hypo-echoic cystic lesion medial to right carotid and inferior right lobe of thyroid. Nuclear scan showed 3 parathyroid adenomas – left superior and inferior and right inferior. In view of the possibility of worsening renal function in patients undergoing parathyroidectomy post renal transplant, it was decided to manage his primary hyperparathyroidism with Cinacalcet. We acknowledge that some of the raised parathyroid hormone level in the past could be related to renal impairment. However he continued to have elevated levels even when the eGFR was between 62 and 74 mL/min/1.73m². His calcium and parathyroid hormone levels have normalised whilst on Cinacalcet.