10.6084/m9.figshare.7517924.v1 Teresa Cristina P. Bonanséa Teresa Cristina P. Bonanséa Monique Nakayama Ohe Monique Nakayama Ohe Cynthia Brandão Cynthia Brandão Cláudia de Francischi Ferrer Cláudia de Francischi Ferrer Lívia Marcela Santos Lívia Marcela Santos Marise Lazaretti-Castro Marise Lazaretti-Castro José Gilberto Henriques Vieira José Gilberto Henriques Vieira Experience with a third-generation parathyroid hormone assay (BIO-PTH) in the diagnosis of primary hyperparathyroidism in a Brazilian population SciELO journals 2018 Primary hyperparathyroidism Bio-PTH intact PTH PTH assays 2018-12-26 05:57:01 Dataset https://scielo.figshare.com/articles/dataset/Experience_with_a_third-generation_parathyroid_hormone_assay_BIO-PTH_in_the_diagnosis_of_primary_hyperparathyroidism_in_a_Brazilian_population/7517924 <div><p>ABSTRACT Objective To evaluate the usefulness of a third-generation PTH assay in the diagnosis of primary hyperparathyroidism (PHPT). Subjects and methods Forty-one PHPT patients (4 men and 37 women) with 61.2 ± 10.9 (mean ± SD) years, were studied and had PTH levels measured with two different methods using the same immunochemiluminescent assay plataform (Elecsys 2010 System, Roche). We compared a second-generation assay (I-PTH) with a third-generation PTH assay (Bio-PTH). Two populations of 423 and 120 healthy adults with serum 25OHD levels above 25 ng/mL were used to define normal values in the I-PTH and Bio-PTH assays respectively. Results Normal PTH values based in the healthy adults population were 24.2-78.0 pg/mL for the I-PTH assay and 19.9-58.5 pg/mL for Bio-PTH assay. In PHPT patients, PTH values ranged from 67 to 553 pg/mL (median: 168 pg/mL) using the I-PTH assay and from 55 to 328 pg/mL (median: 111 pg/mL) using the Bio-PTH assay. Results obtained with the Bio-PTH assay were significantly lower (p < 0.0001, Wilcoxon). In general I-PTH and Bio-PTH showed highly significant correlation (r = 0.952, p < 0.0001). Passing–Bablok analysis gave a regression equation of Bio PTH = 13.44 + 0.59 x intact PTH. PHPT patients had 25OHD levels ranging from 4 to 36 ng/mL (mean 16.2 ng/mL); 35 subjects (85.3%) had values bellow 25 ng/mL. Conclusion Our results demonstrate that both second and third generation PTH methods are strongly correlated in PHPT patients and control subjects. Lower results with Bio-PTH tests are expected in function of the assay specificity determined by the amino-terminal antibody used.</p></div>