Which lab finding indicates CKD-MBD (mineral and bone disorder) activity?

Which lab finding indicates CKD-MBD (mineral and bone disorder) activity?

• A. Low PTH
• B. Elevated PTH
• C. Normal PTH
• D. Decreased calcium

Answer: (B)

In CKD-MBD, the kidneys’ impaired ability to excrete phosphate and activate vitamin D drives a compensatory rise in parathyroid hormone. As phosphate builds up and calcium activity falls, the parathyroids secrete more PTH to restore balance. This secondary hyperparathyroidism reflects ongoing mineral and bone disorder activity, so an elevated PTH level is the best indicator. A low PTH wouldn’t fit CKD-MBD, normal PTH would suggest no active parathyroid response, and reduced calcium alone doesn’t confirm ongoing CKD-MBD without the accompanying parathyroid reaction.

In CKD-MBD, the kidneys’ impaired ability to excrete phosphate and activate vitamin D drives a compensatory rise in parathyroid hormone. As phosphate builds up and calcium activity falls, the parathyroids secrete more PTH to restore balance. This secondary hyperparathyroidism reflects ongoing mineral and bone disorder activity, so an elevated PTH level is the best indicator. A low PTH wouldn’t fit CKD-MBD, normal PTH would suggest no active parathyroid response, and reduced calcium alone doesn’t confirm ongoing CKD-MBD without the accompanying parathyroid reaction.