How to manage elevated alkaline phosphatase levels in patients undergoing dialysis?

From the Guidelines

Managing elevated alkaline phosphatase (ALP) levels in dialysis patients requires identifying and treating the underlying cause while optimizing dialysis parameters. First, determine if the elevation stems from bone disease, liver dysfunction, or other sources through targeted testing including parathyroid hormone (PTH) levels, liver function tests, and bone-specific ALP isoenzymes. For dialysis-related bone disease (renal osteodystrophy), control hyperphosphatemia with phosphate binders such as calcium acetate (667 mg with meals), sevelamer (800-1600 mg with meals), or lanthanum carbonate (500-1000 mg with meals) as suggested by 1. Manage secondary hyperparathyroidism with vitamin D analogs like calcitriol (0.25-1 mcg daily or 1-3 mcg intravenously with dialysis) or paricalcitol (2-5 mcg with dialysis sessions). For severe cases, consider cinacalcet (30-180 mg daily) to directly reduce PTH as mentioned in 1. Ensure adequate dialysis prescription with Kt/V of at least 1.2 for hemodialysis patients and weekly Kt/V of 1.7 for peritoneal dialysis. Monitor calcium, phosphorus, PTH, and ALP levels regularly, typically monthly until stabilized, then quarterly. Nutritional counseling to limit phosphorus intake to 800-1000 mg/day is also essential. These interventions address the mineral bone disorder that commonly causes ALP elevation in dialysis patients by correcting the biochemical abnormalities that drive bone turnover dysregulation. The use of these interventions is supported by the most recent and highest quality studies, including those published in the Annals of Internal Medicine 1. It is also important to consider the potential risks and benefits of each treatment option, as well as the individual patient's needs and medical history, as discussed in 1. By taking a comprehensive and evidence-based approach to managing elevated ALP levels in dialysis patients, healthcare providers can help improve patient outcomes and reduce the risk of complications associated with mineral bone disorder. Key points to consider include:

• Identifying and treating the underlying cause of elevated ALP levels
• Optimizing dialysis parameters to control hyperphosphatemia and secondary hyperparathyroidism
• Using phosphate binders and vitamin D analogs as first-line treatments
• Considering cinacalcet for severe cases of secondary hyperparathyroidism
• Monitoring calcium, phosphorus, PTH, and ALP levels regularly
• Providing nutritional counseling to limit phosphorus intake.

From the FDA Drug Label

In dialysis patients, a fall in serum alkaline phosphatase levels usually antedates the appearance of hypercalcemia and may be an indication of impending hypercalcemia. For dialysis patients, serum calcium, phosphorus, magnesium, and alkaline phosphatase should be determined periodically. A nonaluminum phosphate-binding compound and a low-phosphate diet should be used to control serum phosphorus levels in patients undergoing dialysis.

To manage elevated alkaline phosphatase levels in patients undergoing dialysis, it is essential to:

• Monitor serum alkaline phosphatase levels periodically 2
• Control serum phosphorus levels using a nonaluminum phosphate-binding compound and a low-phosphate diet 2
• Monitor serum calcium levels to avoid hypercalcemia, as a fall in serum alkaline phosphatase levels may indicate impending hypercalcemia 2
• Adjust calcitriol dosage as needed to avoid hypercalcemia and hyperphosphatemia 2 2

From the Research

Management of Elevated Alkaline Phosphatase Levels

Elevated alkaline phosphatase levels in patients undergoing dialysis can be managed through various approaches. The following are some key points to consider:

• The kidney is a likely source of increased serum intestinal-type phosphatase activity noted in patients with chronic renal failure 3.
• Elevated total serum alkaline phosphatase levels have been associated with higher mortality in patients on peritoneal dialysis 4.
• Treatment with paricalcitol has been shown to result in lower serum calcium, calcium-phosphorus product, parathyroid hormone, and alkaline phosphatase levels compared to treatment with calcitriol 5.
• Managing secondary hyperparathyroidism, a common complication of chronic kidney disease, is crucial in preventing the development of bone disease and vascular calcification 6.
• Maintaining acceptable levels of mineral metabolism parameters, such as calcium, phosphorus, and vitamin D, is essential in slowing down or preventing the development of secondary hyperparathyroidism 6.

Key Considerations

Some key considerations in managing elevated alkaline phosphatase levels in dialysis patients include:

• Monitoring serum alkaline phosphatase levels regularly to assess the effectiveness of treatment 4.
• Adjusting treatment regimens, such as switching from calcitriol to paricalcitol, to achieve better control of mineral metabolism parameters 5.
• Considering the potential risks of bone disorders and mineral disarrays in CKD patients 7.
• Evaluating the association between alkaline phosphatase levels and mortality in peritoneal dialysis patients 4.

Treatment Options

Treatment options for managing elevated alkaline phosphatase levels in dialysis patients may include:

• Vitamin D receptor activators, such as calcitriol, paricalcitol, and doxercalciferol 7, 5.
• Calcimimetics, such as cinacalcet 7.
• Phosphate binding agents and dietary phosphorus restriction 5.
• Recombinant parathyroid hormone (teriparatide) and receptor activator of nuclear factor-kappaB ligand modulators (denosumab) 7.