NBME 23 Answers ↦
Basically PTH keeps telling the kidney that it wants it to reabsorb Calcium and dump phosphate, but the kidney is broken and cant do that.
@mguan1993 yes it does! With secondary hyperPTH due to CKD = incr. phosphate, dec. Ca2+ and incr. PTH. This can then progress to tertiary hyperPTH from longstanding secondary hyperPTH as a result of parathyroid HYPERPLASIA --> autonomously (refractory) functioning parathyroid. This will actually lead to INCREASED Ca2+, and significantly INCREASED PTH. Treatment would be surgical removal of the parathyroid glands. Sources: DIT and FA18 p340