From the Guidelines
Patients on Prolia should have their calcium, phosphate, and renal function levels monitored regularly, with a focus on serum calcium and creatinine levels, as well as parathyroid hormone (PTH) levels in patients with risk factors for secondary hyperparathyroidism. When considering the management of patients on Prolia, it is crucial to prioritize monitoring that directly impacts morbidity, mortality, and quality of life. Although the provided evidence primarily discusses the management of X-linked hypophosphataemia, the principles of monitoring calcium, phosphate, and renal function can be applied to patients on Prolia, given the drug's mechanism of action and potential effects on bone metabolism and calcium levels 1. Key aspects to monitor include:
- Serum calcium levels, particularly in patients at risk for hypocalcemia, such as those with severe renal impairment or parathyroid disorders.
- Renal function tests, including creatinine and estimated glomerular filtration rate (eGFR), as renal impairment can increase the risk of hypocalcemia.
- Phosphate levels, as alterations in phosphate metabolism can occur in the context of bone diseases and treatments affecting bone resorption.
- Parathyroid hormone (PTH) levels in patients with risk factors for secondary hyperparathyroidism, as Prolia's effect on bone resorption could potentially influence PTH levels and calcium metabolism. It is essential to correct any deficiencies in calcium and vitamin D before starting Prolia and to advise patients to report symptoms of hypocalcemia, which would prompt immediate testing and potential intervention 1. Regular monitoring and prompt management of any abnormalities are critical to preventing complications and ensuring the best possible outcomes for patients on Prolia, focusing on minimizing morbidity, mortality, and maximizing quality of life.
From the FDA Drug Label
In patients without advanced chronic kidney disease who are predisposed to hypocalcemia and disturbances of mineral metabolism (e. g. history of hypoparathyroidism, thyroid surgery, parathyroid surgery, malabsorption syndromes, excision of small intestine, treatment with other calcium-lowering drugs), assess serum calcium and mineral levels (phosphorus and magnesium) 10 to14 days after Prolia injection
Patients with Advanced Chronic Kidney Disease ... evaluate for the presence of chronic kidney disease mineral and bone disorder with intact parathyroid hormone (iPTH), serum calcium, 25(OH) vitamin D, and 1,25(OH)2 vitamin D prior to decisions regarding Prolia treatment
Monitor serum calcium weekly for the first month after Prolia administration and monthly thereafter
The bloods that should be checked whilst a patient is on Prolia are:
- Serum calcium
- Phosphorus
- Magnesium
- Intact parathyroid hormone (iPTH)
- 25(OH) vitamin D
- 1,25(OH)2 vitamin D These tests are used to monitor for hypocalcemia and mineral metabolism changes, especially in patients with advanced chronic kidney disease 2.
From the Research
Blood Tests for Patients on Prolia
While on Prolia (denosumab), patients should have the following blood tests checked:
- Serum calcium levels: This is crucial as denosumab can cause hypocalcemia, especially in patients with chronic kidney disease (CKD) or vitamin D deficiency 3, 4, 5, 6, 7
- Phosphate levels: Hypophosphatemia can occur alongside hypocalcemia, as seen in a case report where a patient developed severe hypocalcemia and hypophosphatemia after denosumab administration 3
- Vitamin D levels: Vitamin D deficiency can increase the risk of hypocalcemia in patients on denosumab, and supplementing with vitamin D can help stabilize calcium and phosphate levels 3, 6
- Parathyroid hormone (PTH) levels: PTH levels can be affected by denosumab treatment, and monitoring PTH levels can help assess the risk of hypocalcemia 4, 6
- Kidney function tests: Patients with CKD are at higher risk of hypocalcemia when on denosumab, and monitoring kidney function can help identify patients who require closer monitoring 4, 5, 6, 7
- Electrolyte levels: Patients on denosumab may require intensive care monitoring for replacement of electrolytes, including calcium and phosphate 3
Monitoring Frequency
The frequency of monitoring these blood tests may vary depending on the patient's individual risk factors, such as CKD stage, vitamin D deficiency, and history of hypocalcemia. Close monitoring is essential, especially in patients with advanced CKD or those who have developed hypocalcemia after denosumab treatment 4, 5, 6, 7