Читать книгу Essential Endocrinology and Diabetes - Richard I. G. Holt - Страница 93

Typical adult reference ranges are listed for a number of hormones in Table 4.1. Whenever possible, hormones are measured in molar units (e.g. pmol/L) or mass units (e.g. ng/L). However, this is not possible for complex hormones such as the glycoproteins thyroid‐stimulating hormone (TSH), luteinizing hormone (LH) and follicle‐stimulating hormone (FSH), because they circulate in a variety of slightly different forms (‘microheterogeneity’). In this scenario, international reference preparations are agreed, with potency expressed in ‘units’ (U) and their subdivisions [e.g. milliunits (mU)]. Potency is assigned after large collaborative trials involving many laboratories worldwide using a range of assay platforms and physical analytical techniques. Patient results are then expressed relative to the reference data.