Diagnostic Values of Intraoperative (1-84) Parathyroid Hormone Levels are Superior to Intact Parathyroid Hormone for Successful Parathyroidectomy in Patients With Chronic Kidney Disease.

OBJECTIVE:Persistent secondary hyperparathyroidism (SHPT) may occur because of residual cervicothoracic parathyroids in parathyroidectomy (PTX) patients with chronic kidney disease. We prospectively compared the predictive values of intraoperative plasma (1-84) parathyroid hormone (PTH) and intact PTH (iPTH) levels to improve the safety and efficacy of PTX. METHODS:We included 100 healthy controls, 162 stage 5 chronic kidney disease patients without SHPT, and 214 patients who underwent PTX because of SHPT. Plasma iPTH and (1-84) PTH levels were measured before incision (io-iPTH0 and io-[1-84]PTH0, respectively) and 10 minutes (io-iPTH10 and io-[1-84]PTH10, respectively) and 20 minutes (io-iPTH20 and io-[1-84]PTH20, respectively) after removing all parathyroids. The percentage reduction of iPTH and (1-84) PTH at 10 minutes (io-iPTH10% and io-[1-84]PTH10%, respectively) and 20 minutes (io-iPTH20%, and io-[1-84]PTH20%, respectively) was calculated. iPTH and (1-84) PTH were measured using second- and third-generation PTH assays, respectively. RESULTS:Compared with the controls and non-PTX patients, the PTX group had more obvious mineral metabolism disorders. There were 187 successful PTXs, 19 patients with persistent SHPT, and 8 patients lost to follow-up. The receiver operating characteristic curves revealed that io-(1-84)PTH10% >86.6% and io-(1-84)PTH20% >87.5% suggested successful PTX. The sensitivity of io-iPTH20% and io-(1-84)PTH20% were higher than those at the timepoint of 10 minutes. Moreover, the specificity and sensitivity of the (1-84) PTH reduction percentage were superior to that of iPTH. CONCLUSION:Intraoperative reduction percentages of plasma (1-84) PTH levels are superior to iPTH for accurately predicting successful PTX, especially at 20 minutes after all cervicothoracic parathyroids had been resected.