title: Sequential changes in plasma intact and whole parathyroid hormone levels during parathyroidectomy for secondary hyperparathyroidism.
abstract: Most commercial assays for intact parathyroid hormone (iPTH) cross-react with non-PTH1-84 fragments (likely to be PTH7-84). We aimed to evaluate a whole PTH assay that measured only PTH1-84 by comparing it with an assay measuring iPTH levels during parathyroidectomy in secondary hyperparathyroidism (HPT). Twenty-eight patients with secondary HPT who underwent total parathyroidectomy with autotransplantation served as subjects. Blood samples for postoperative assay were drawn after anesthesia; immediately prior to excision of the last parathyroid gland; and at 5, 10, and 15 minutes after excision. The PTH7-84 level was calculated by subtracting the whole PTH value from the iPTH value. Plasma whole PTH decreased more rapidly than iPTH after parathyroidectomy (p < 0.0001). PTH levels that decreased by 50% or more from levels prior to excision to 10 minutes after excision were used to predict successful parathyroidectomy; decreases in whole PTH substantiated curative surgery for all patients without introducing false-positive and false-negative results. iPTH levels decreased by at least 50% in only 16 patients at 10 minutes after excision without false-positive results. Out of 11 cases in which iPTH decreased less than 50%, two were true-negatives and nine were false-negatives. Decreases in whole PTH levels more accurately reflect surgical outcome than do decreases in iPTH levels during parathyroidectomy in secondary HPT patients. Even though the quick iPTH assay is used infrequently during surgery for secondary HPT, our results suggest that a quick whole PTH assay may be more useful than the iPTH assay currently used in parathyroidectomy procedures for secondary HPT.
authors.affiliation: Noguchi Thyroid Clinic and Hospital Foundation, 6-33 Noguchi-Nakamachi, 874-0932 Beppu Oita, Japan. yama@noguchi-med-or.jp
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Yamashita
authors.forename: Tom
authors.initials: T
authors.lastname: Cantor
authors.forename: Shinya
authors.initials: S
authors.lastname: Uchino
authors.forename: Shin
authors.initials: S
authors.lastname: Watanabe
authors.forename: Takahiro
authors.initials: T
authors.lastname: Ogawa
authors.forename: Taiki
authors.initials: T
authors.lastname: Moriyama
authors.forename: Yuji
authors.initials: Y
authors.lastname: Takamatsu
authors.forename: Masafumi
authors.initials: M
authors.lastname: Fukagawa
authors.forename: Shiro
authors.initials: S
authors.lastname: Noguchi
mesh_terms: D005260:Female; D006801:Humans; D006962:Hyperparathyroidism, Secondary / Q000097:blood* / Q000601:surgery*; D015592:Immunoradiometric Assay; D007432:Intraoperative Period; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood*; D016105:Parathyroidectomy; D013997:Time Factors
chemical_list: D010281:Parathyroid Hormone