Because calcium is our most critical electrolyte, the calcium feedback mechanism is crucial to maintaining homeostasis (balance). The kidneys play a significant role in this process. When the parathyroid glands release parathyroid hormone (PTH) to stimulate the bones to release calcium, this same hormone also stimulates the kidneys to reabsorb calcium, convert vitamin D3 to calcitriol, and eliminate phosphorus through urinary waste.
Phosphorus and Hypoparathyroidism
Without PTH, the kidneys are not given the signal to eliminate phosphorus from the blood. If phosphorus levels in the body are high, absorption of oral calcium is limited, which increases symptoms related to hypocalcemia. In addition, phosphorus binds with calcium, and over time high phosphorus levels can lead to calcium deposits on the kidneys (kidney stones), brain, or other areas of the body. For this reason, it is important for people living with chronic hypoparathyroidism to monitor their kidney function regularly.