Active vitamin D should be used to suppress PTH in which CKD stage?

Active vitamin D should be used to suppress PTH in which CKD stage?

• A. Stage 1
• B. Stage 2
• C. Stage 5
• D. Stage 3 or 4

Answer: (D)

Active vitamin D helps suppress PTH when CKD has progressed enough to reduce the kidney’s production of calcitriol, which lowers intestinal calcium absorption and contributes to secondary hyperparathyroidism. This process typically becomes clinically relevant in CKD stages where kidney function is diminished but before dialysis is needed, namely stages 3 and 4. In earlier CKD (stages 1–2), PTH elevation is not usually prominent, so using active vitamin D is not routinely indicated. In the dialysis stage, management is more complex and choices about active vitamin D become more nuanced due to risks of hypercalcemia and vascular calcification, though it can still be used. Therefore, the stage where active vitamin D is most clearly indicated to suppress PTH is stage 3 or 4.

Active vitamin D helps suppress PTH when CKD has progressed enough to reduce the kidney’s production of calcitriol, which lowers intestinal calcium absorption and contributes to secondary hyperparathyroidism. This process typically becomes clinically relevant in CKD stages where kidney function is diminished but before dialysis is needed, namely stages 3 and 4. In earlier CKD (stages 1–2), PTH elevation is not usually prominent, so using active vitamin D is not routinely indicated. In the dialysis stage, management is more complex and choices about active vitamin D become more nuanced due to risks of hypercalcemia and vascular calcification, though it can still be used. Therefore, the stage where active vitamin D is most clearly indicated to suppress PTH is stage 3 or 4.