Hypocalcemia After the Administration of Denosumab in a Patient With Osteoporotic Fracture and Vitamin D Deficiency

Abstract

Denosumab is a potent antiresorptive agent used for the treatment of osteoporosis and the prevention of skeletal-related events in patients with multiple myeloma or bone metastasis from solid tumors. Although denosumab generally seems to be safe and well tolerated, denosumab-associated hypocalcemia may occur, and the majority of cases are asymptomatic or mild. Underlying malignancy, renal failure, calcium or vitamin D deficiency, and high bone turnover have been reported as risk factors for hypocalcemia. Here, the author reports a case of hypocalcemia and hypophosphatemia following the administration of denosumab for the treatment of osteoporotic fracture in a patient with underlying but unrecognized severe vitamin D deficiency. Following the supplementation of calcium, vitamin D, and phosphorus, serum calcium and phosphorus levels returned to normal levels after about 2 weeks. To avoid denosumab-associated hypocalcemia, calcium and vitamin D status, as well as renal function should be assessed and corrected if appropriate. J Endocrinol Metab. 2022;12(3):111-115 doi: https://doi.org/10.14740/jem810