Is there a role for parathyroidectomy in CKD?
Ideally, parathyroidectomy should be avoided with the initiation of early therapy to prevent the development of severe hyperparathyroidism with monoclonal nodular transformation of the parathyroid gland.
As the parathyroid glands develop monoclonal nodularity, there is loss of both the calcium-sensing receptor and the vitamin D receptor. Thus, as the parathyroid glands develop large nodules, they are no longer responsive to normal physiologic control and are resistant to pharmacologic therapy, which is a poor prognostic sign.
An attempt should be made to treat patients early before severe hyperparathyroidism develops. In patients with severe hyperparathyroidism, treatment with high-dose VDRAs and cinacalcet may be necessary; however, if severe hyperparathyroidism persists and patients develop hypercalcemia and hyperphosphatemia, a parathyroidectomy may be required.
There is much controversy as to the best approach for parathyroidectomy, whether a subtotal parathyroidectomy should be performed or a total parathyroidectomy with reimplantation of part of a gland into either the forearm or the sternocleidomastoid muscle.
The problem of reimplantation is that frequently the implanted tissue becomes fibrotic and does not function, or the patient (rarely) could develop parathyroidomatosis, in which microscopic cells produce high levels of PTH. A relatively common complication following parathyroidectomy is the development of the hungry bone syndrome.
This occurs in patients with long-standing, severe hyperparathyroidism. Following the rapid drop in PTH concentrations, the bones rapidly take up both calcium and phosphate as they remineralize, resulting in hypocalcemia and possibly hypophosphatemia.
These patients require high doses of calcium and calcitriol to prevent symptomatic hypocalcemia. Depending on the severity of the preexisting hyperparathyroidism, this can last for weeks to even months.
Experienced parathyroid surgeons may be able to perform partial parathyroidectomy, while trying to selectively remove nodular tissue, and leave behind normal-appearing gland.
Surgery should be performed utilizing intraoperative PTH measurements. Although several studies have suggested improved survival in dialysis patients following parathyroidectomy, a cohort analysis of USRDS ESRD database demonstrated increased morbidity following parathyroidectomy.
