Bruno Madeo1, Sara De Vincentis2,3, Andrea Repaci4, Paola Altieri4, Valentina Vicennati4, Elda Kara3,5, Fabio Vescini5, Pierluigi Amadori6, Antonio Balestrieri7, Uberto Pagotto4, Manuela Simoni2,3, Vincenzo Rochira2,3. 1. Unit of Endocrinology, Department of Medical Specialties, Azienda Ospedaliero-Universitaria di Modena, Ospedale Civile di Baggiovara, 41126, Modena, Italy. bruno.madeo@unimore.it. 2. Unit of Endocrinology, Department of Medical Specialties, Azienda Ospedaliero-Universitaria di Modena, Ospedale Civile di Baggiovara, 41126, Modena, Italy. 3. Unit of Endocrinology, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41126, Modena, Italy. 4. Unit of Endocrinology, DIMEC Alma Mater Studiorum Bologna, Policlinico S. Orsola-Malpighi, 40138, Bologna, Italy. 5. Endocrinology and Metabolism Unit, University-Hospital S. Maria della Misericordia of Udine, 33100, Udine, Italy. 6. Unit of Endocrinology, Azienda Provinciale Servizi Sanitari Trento, 38122, Trento, Italy. 7. Endocrinology and Diabetology Unit, Department of Internal Medicine, M. Bufalini Hospital, 47521, Cesena, Italy.
Abstract
PURPOSE: The diagnosis of primary hyperparathyroidism (PHPT) and chronic hypoparathyroidism (HypoPT) is still challenging, especially in patients asymptomatic or with non-classical phenotypes and for physicians not skilled in calcium-phosphorous (Ca-P) disorders. The serum calcium/phosphorous (Ca/P) ratio has been proposed as accurate index to identify PHPT, while it has never been tested in HypoPT. The aim of this study is to investigate the diagnostic power of the serum Ca/P ratio in the diagnosis of primary parathyroid dysfunctions (both PHPT and HypoPT) in a large series of data. METHODS: A multicentric, retrospective, cross-sectional study (ClinicalTrials.gov: NCT03747029) was carried out including 432 PHPT patients and 217 HypoPT patients compared with 389 controls. Serum Ca, P, creatinine, parathyroid hormone and 25OH-vitamin D were collected. Serum Ca and P were expressed in mmol/L. Ca/P diagnostic performance was evaluated by receiver operating characteristic (ROC) curve, sensitivity, specificity and accuracy. RESULTS: The Ca/P ratio was significantly higher in PHPT and lower in HypoPT patients than controls (p < 0.0001). At ROC curve analysis, the Ca/P ratio above 2.55 was defined to identify PHPT patients (sensitivity 85.7%, specificity 85.3%) and below 1.78 to identify HypoPT patients (sensitivity 88.2%, specificity 87.9%). CONCLUSIONS: The Ca/P ratio is a highly accurate index to identify PHPT when Ca/P is above 2.55 and HypoPT when it is below 1.78. These results demonstrate the reliability of this index to rule in/out primary parathyroid dysfunctions and remark the importance of measuring serum P in clinical practice.
PURPOSE: The diagnosis of primary hyperparathyroidism (PHPT) and chronic hypoparathyroidism (HypoPT) is still challenging, especially in patients asymptomatic or with non-classical phenotypes and for physicians not skilled in calcium-phosphorous (Ca-P) disorders. The serum calcium/phosphorous (Ca/P) ratio has been proposed as accurate index to identify PHPT, while it has never been tested in HypoPT. The aim of this study is to investigate the diagnostic power of the serum Ca/P ratio in the diagnosis of primary parathyroid dysfunctions (both PHPT and HypoPT) in a large series of data. METHODS: A multicentric, retrospective, cross-sectional study (ClinicalTrials.gov: NCT03747029) was carried out including 432 PHPTpatients and 217 HypoPTpatients compared with 389 controls. Serum Ca, P, creatinine, parathyroid hormone and 25OH-vitamin D were collected. Serum Ca and P were expressed in mmol/L. Ca/P diagnostic performance was evaluated by receiver operating characteristic (ROC) curve, sensitivity, specificity and accuracy. RESULTS: The Ca/P ratio was significantly higher in PHPT and lower in HypoPTpatients than controls (p < 0.0001). At ROC curve analysis, the Ca/P ratio above 2.55 was defined to identify PHPTpatients (sensitivity 85.7%, specificity 85.3%) and below 1.78 to identify HypoPTpatients (sensitivity 88.2%, specificity 87.9%). CONCLUSIONS: The Ca/P ratio is a highly accurate index to identify PHPT when Ca/P is above 2.55 and HypoPT when it is below 1.78. These results demonstrate the reliability of this index to rule in/out primary parathyroid dysfunctions and remark the importance of measuring serum P in clinical practice.
Entities:
Keywords:
Disorders of calcium/phosphate metabolism; Hyperparathyroidism; Hypoparathyroidism; Parathyroid-related disorders; Screening