title: How the reference values for serum parathyroid hormone concentration are (or should be) established?
abstract: Well-validated reference values are necessary for a correct interpretation of a serum PTH concentration. Establishing PTH reference values needs recruiting a large reference population. Exclusion criteria for this population can be defined as any situation possibly inducing an increase or a decrease in PTH concentration. As recommended in the recent guidelines on the diagnosis and management of asymptomatic primary hyperparathyroidism, PTH reference values should be established in vitamin D-replete subjects with a normal renal function with possible stratification according to various factors such as age, gender, menopausal status, body mass index, and race. A consensus about analytical/pre-analytical aspects of PTH measurement is also needed with special emphasis on the nature of the sample (plasma or serum), the time and the fasting/non-fasting status of the blood sample. Our opinion is that blood sample for PTH measurement should be obtained in the morning after an overnight fast. Furthermore, despite longer stability of the PTH molecule in EDTA plasma, we prefer serum as it allows to measure calcium, a prerequisite for a correct interpretation of a PTH concentration, on the same sample. Once a consensus is reached, we believe an important international multicentre work should be performed to recruit a very extensive reference population of apparently healthy vitamin D-replete subjects with a normal renal function in order to establish the PTH normative data. Due to the huge inter-method variability in PTH measurement, a sufficient quantity of blood sample should be obtained to allow measurement with as many PTH kits as possible.
authors.affiliation: Service des Explorations Fonctionnelles, Hôpital Necker-Enfants Malades, 149 rue de Sèvres, 75015, Paris, France. Jean-claude.souberbielle@nck.aphp.fr.|Université René Descartes, 75015, Paris, France. Jean-claude.souberbielle@nck.aphp.fr.
authors.forename: J-C
authors.initials: JC
authors.lastname: Souberbielle
authors.affiliation: Service des Explorations Fonctionnelles, Hôpital Necker-Enfants Malades, 149 rue de Sèvres, 75015, Paris, France.|Université René Descartes, 75015, Paris, France.
authors.forename: F
authors.initials: F
authors.lastname: Brazier
authors.affiliation: Service des Explorations Fonctionnelles, Hôpital Necker-Enfants Malades, 149 rue de Sèvres, 75015, Paris, France.|Université René Descartes, 75015, Paris, France.
authors.forename: M-L
authors.initials: ML
authors.lastname: Piketty
authors.affiliation: Rheumatology Department, Cochin University Hospital, 75014, Paris, France.
authors.forename: C
authors.initials: C
authors.lastname: Cormier
authors.affiliation: Ordinario di Medicina Interna, Responsabile UOC Medicina Interna e Malattie Metaboliche dell'Osso (TMC 04), « Sapienza » Università di Roma, Rome, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Minisola
authors.affiliation: Clinical Chemistry Department, Sart Tilman University Hospital, Liège, Belgium.
authors.forename: E
authors.initials: E
authors.lastname: Cavalier
mesh_terms: D006801:Humans; D049950:Hyperparathyroidism, Primary / Q000097:blood* / Q000175:diagnosis*; D010281:Parathyroid Hormone / Q000097:blood*; D012016:Reference Values
chemical_list: D010281:Parathyroid Hormone
keywords: Chronic kidney disease; Parathyroid hormone (PTH); Primary hyperparathyroidism; Reference values; Vitamin D