Calcium, Phosphate, and Magnesium Metabolism in Chronic Kidney Disease

Disturbances in calcium (Ca2+), phosphate (Pi), and magnesium (Mg2+) homeostasis contribute to Chronic Kidney Disease Mineral and Bone Disorders (CKD-MBD), which encompasses abnormalities in mineral metabolism and bone, extraskeletal calcification, and cardiovascular disease. Although the role of excess Pi is unequivocal in CKD-MBD, the role of Ca2+ and Mg2+ is less clear. Understanding how Ca2+, Pi, and Mg2+ disturbances affect the onset and progression of CKD-MBD is essential to achieving the ultimate goal of developing individualized effective treatments that target different facets of CKD-MBD pathophysiology in each patient. Pi load to the organism can be reduced by dietary modifications, binders, and/or modifiers of intestinal epithelial transport. Ca2+ and/or Mg2+ supplements (or avoidance) should be prescribed only to those who will benefit based on Ca2+ and Mg2+ status. Multiple therapies targeting more than one pathophysiologic factor involved in Ca2+, Pi, and Mg2+ balance will be required to treat CKD-MBD.