Controversies in measuring parathyroid hormone

Abstract

Parathyroid hormone is a 84 aminoacid protein very important in the diagnosis of hypocalcemia and hypercalcemia, hyper and hypoparathyroidism and in the follow up of bone disorders in renal patients. Even if the first assay was published in 1963, even today its measurement in the laboratory is a partially-resolved challenge. Common problems are circulating fragments which are recognized by second-generation assays, the different specificity of antibodies, the lack of a reference method, the lack of assay standardization and the lack of definition about which is the ideal population to define a normal reference range. Improvements in all of these aspects are required to make assays comparable. It is important that physicians know these aspects and use them as tools to interpret one result. It is essential that laboratories implement strict internal quality control procedures and participation in external quality assessment schemes to evaluate the performance between the same and other methods.