Emir Muzurović1,2, Karin Zibar Tomšić3, Snežana Vujošević4,5, Milan Petakov6. 1. Department of Internal Medicine, Endocrinology Section, Clinical Center of Montenegro, Kruševac bb, Podgorica, 81000, Montenegro. dremir@t-com.me. 2. Faculty of Medicine, University of Montenegro, Podgorica, 81000, Montenegro. dremir@t-com.me. 3. Department of Endocrinology, University Hospital Centre Zagreb, Zagreb, Croatia. 4. Department of Internal Medicine, Endocrinology Section, Clinical Center of Montenegro, Kruševac bb, Podgorica, 81000, Montenegro. 5. Faculty of Medicine, University of Montenegro, Podgorica, 81000, Montenegro. 6. Clinic for Endocrinology, Diabetes and Metabolic Diseases, Clinical Center of Serbia, Faculty of Medicine, University of Belgrade, Beograd, Serbia.
Abstract
OBJECTIVE: While activation of the calcium (Ca) sensing receptor (CaSR) suppresses parathyroid hormone (PTH) secretion, calcitonin (CT) secretion is stimulated via CaSR. The aim of this study was to evaluate PTH and CT responses during a calcium infusion test (CIT) in patients with primary hyperparathyroidism (PHPT). METHODS: This pivotal prospective study included 64 patients (44 PHPT patients vs. 20 healthy controls [HCs], median age 57 [25-79] vs. 56 [39-74] years). All PHPT patients underwent parathyroidectomy (PTX). A week before and 1 month after PTX, the CIT was performed (bolus infusion of Ca gluconate 0.2 ml/kg body weight), followed by plasma sampling for Ca2+, PTH, and CT at 0, 1, 2, 3, 5, 8, and 10 min. RESULTS: PTH suppression was lower in PHPT patients compared to HCs (49.82 vs. 64.06%, p = 0.006), but after PTX suppression, it was higher (76.3%, p < 0.001). PHPT patients had attenuated CT response vs. HCs during the CIT (3.1- vs. 8.0-fold increase, p < 0.001), but after PTX, it improved (5.8-fold increase). The PTHmin > 19.3 ng/l and CTmax ≤ 27.5 ng/l cut-off values predict diagnosis of PHPT (sensitivity 90.9%, 97.7%, and specificity 100%, 75%, respectively). Patients with adenoma had lower basal CT levels vs. hyperplasia both before and after PTX (4.5 vs. 6.8 and 5.4 vs. 7.9 ng/l, respectively, p = 0.008, p = 0.018). CONCLUSION: PTH and CT responses during the CIT in PHPT patients may be an additional diagnostic tool. The CIT could play a role in both the diagnosis of PHPT and in the differential diagnosis between adenoma and hyperplasia.
OBJECTIVE: While activation of the calcium (Ca) sensing receptor (CaSR) suppresses parathyroid hormone (PTH) secretion, calcitonin (CT) secretion is stimulated via CaSR. The aim of this study was to evaluate PTH and CT responses during a calcium infusion test (CIT) in patients with primary hyperparathyroidism (PHPT). METHODS: This pivotal prospective study included 64 patients (44 PHPT patients vs. 20 healthy controls [HCs], median age 57 [25-79] vs. 56 [39-74] years). All PHPT patients underwent parathyroidectomy (PTX). A week before and 1 month after PTX, the CIT was performed (bolus infusion of Ca gluconate 0.2 ml/kg body weight), followed by plasma sampling for Ca2+, PTH, and CT at 0, 1, 2, 3, 5, 8, and 10 min. RESULTS: PTH suppression was lower in PHPT patients compared to HCs (49.82 vs. 64.06%, p = 0.006), but after PTX suppression, it was higher (76.3%, p < 0.001). PHPT patients had attenuated CT response vs. HCs during the CIT (3.1- vs. 8.0-fold increase, p < 0.001), but after PTX, it improved (5.8-fold increase). The PTHmin > 19.3 ng/l and CTmax ≤ 27.5 ng/l cut-off values predict diagnosis of PHPT (sensitivity 90.9%, 97.7%, and specificity 100%, 75%, respectively). Patients with adenoma had lower basal CT levels vs. hyperplasia both before and after PTX (4.5 vs. 6.8 and 5.4 vs. 7.9 ng/l, respectively, p = 0.008, p = 0.018). CONCLUSION: PTH and CT responses during the CIT in PHPT patients may be an additional diagnostic tool. The CIT could play a role in both the diagnosis of PHPT and in the differential diagnosis between adenoma and hyperplasia.
Authors: K L Becker; O L Silva; L A Wisneski; J Cyrus; R H Snider; C F Moore; G A Higgins Journal: Am J Med Sci Date: 1980 Jul-Aug Impact factor: 2.378