Endocrine Abstracts

JOINT1252

Mineral and bone disorders (MBD) associated with chronic kidney disease (CKD), known as CKD-MBD, involve key alterations including hyperphosphatemia, low vitamin D levels, hypocalcemia, and secondary hyperparathyroidism (SHPT). These changes disrupt bone and mineral metabolism, leading to renal osteodystrophy and increased fracture risk. The management of CKD-MBD and associated osteoporosis is often a challenge in current practice. We report the challenges encountered in managing a series of dialysis patients under the care of our Endocrinology Department. The first case involves a 75-year-old male undergoing peritoneal dialysis with SHPT and osteoporosis (forearm T-score of -5.8). His parathyroid hormone (PTH) level was 1063 pg/mL, prompting a 99mTc-MIBI scintigraphy, which revealed a right inferior parathyroid adenoma and left inferior hyperplastic parathyroid gland. Treatment with cinacalcet was initiated but proved inadequate, as PTH levels increased to 1138 pg/mL two years later, with a corrected calcium level of 11.1 mg/dL. Parathyroidectomy (PTx) was advised but deferred due to his fragility, opting for conservative treatment. The second case involves a 55-year-old woman on hemodialysis (HD) with a history of subtotal PTx, with persistent SPTH (levels of 1655 pg/mL), with a corrected calcium level of 9 mg/dL. Post-PTx 99mTc-MIBI scintigraphy identified a left inferior parathyroid adenoma, and she subsequently underwent total PTx. Postoperatively, her PTH level decreased to 300.9 pg/mL, while her corrected calcium level dropped to 7.8 mg/dL despite supplementation with 1800 mg of calcium and 1.5 µg of alfacalcidol daily. Osteoporosis (forearm T-score of -4.5) treatment with denosumab was postponed due to hypocalcemia risks. The third case pertains to a 47-year-old woman on HD with SHPT (PTH levels of 2544 pg/mL) who underwent total PTx. However, PTH remained elevated at 2891 pg/mL, with a corrected calcium level of 7.7 mg/dL. A subsequent 99mTc-MIBI scintigraphy identified two additional hyperplastic parathyroid glands, indicating a total of six parathyroid glands. Due to marked improvement in her general symptoms and bone mineral density after the first PTx, conservative management was decided until further evaluations. The final case concerns a 74-year-old woman on HD with osteoporosis (femoral neck T-score of -3.5). She presented with a PTH level of 434 pg/mL and a corrected calcium level of 9.5 mg/dL. Treatment with denosumab, in combination with alfacalcidol, was initiated, resulting in a significant and prolonged drop in calcium levels to 6.86 mg/dL one month after denosumab administration. These cases highlight the complexity of managing CKD-MBD in dialysis patients.