Problems with the PTH assays.
Even if the first assay for parathyroid hormone (PTH) was published in the early 1960s, its determination remains a challenge even today. Indeed, in the circulation, PTH is present in its active form (PTH 1-84), but many PTH fragments can also be present. These fragments accumulate when renal function declines and are recognized, at different extents, by the 2nd generation ("intact") PTH assays that are widely used in the clinical laboratories. Some assays, called "3rd generation PTH" do not recognize these fragments, but are not available everywhere. Hence, different problems are also linked with PTH determination. Among them, one can cite the lack of a reference method, the lack of standardization of the assays and, sometimes, the lack of consistent reference range. We can also point out stability problems and a large intra-individual variation. A workgroup is working on these problems under the auspices of the IFCC and we hope that some of these problems will be resolved in the next years. In this article, we will discuss all the possible issues of PTH determination.
Department of Clinical Chemistry, CHU de Liège, Liège, Belgium; University of Liège, Liège, Belgium. Electronic address: Etienne.cavalier@chu.ulg.ac.be.
Etienne
E
Cavalier
Department of Nephrology, Dialysis, Transplantation, CHU de Liège, 4000 Liège, Belgium.
Pierre
P
Delanaye
University of Liège, Liège, Belgium.
Laurent
L
Nyssen
Service d'exploration fonctionnelles, hôpital Necker-Enfants-Malades, 75014 Paris, France.
Jean-Claude
JC
Souberbielle
D000595:Amino Acid Sequence; D006801:Humans; D007118:Immunoassay; D008969:Molecular Sequence Data; D010281:Parathyroid Hormone / Q000032:analysis*; D010446:Peptide Fragments / Q000032:analysis; D012015:Reference Standards; D012016:Reference Values; D051436:Renal Insufficiency, Chronic / Q000175:diagnosis / Q000378:metabolism
D010281:Parathyroid Hormone; D010446:Peptide Fragments
Dosage de l’hormone parathyroïdienne; Fragments de PTH; PTH assays; PTH fragments; Parathyroid hormone measurement; Trousses de PTH