Parathyroid Glands in Chronic Kidney Disease by Unknown

Author:Unknown
Language: eng
Format: epub
ISBN: 9783030437695
Publisher: Springer International Publishing

Reference Range

In hemodialyzed patients, KDIGO guidelines recommend to maintain the serum PTH levels within twice to 9 times the upper normal limit of the reference range [35]. Accordingly, the definition of the upper limit of the PTH normal range is of prime importance. This raises the question of the inclusion/exclusion criteria which should be applied when recruiting a reference population to establish PTH normal values. Exclusion criteria for this population can be defined as any situation possibly inducing an increase or a decrease in PTH concentration. Among these conditions, low serum 25-hydroxyvitamin D (25OHD) concentration is highly frequent in the general population [36] and should thus be prevalent in an apparently healthy group recruited to establish normal PTH values. Excluding subjects with vitamin D insufficiency from a reference population for serum PTH reference values seems thus logical and has been strongly recommended in the two most recent guidelines on the diagnosis and management of asymptomatic PHPT [18]. We have also demonstrated in several studies that excluding subjects with a low serum 25OHD concentration from a reference population decreased the upper normal limit for serum PTH by 20–35%, depending on the assay considered [37, 38]. Besides 25(OH)D levels, renal function should also be taken into consideration when establishing PTH reference values. Indeed, PTH generally rises when estimated glomerular filtration rate (eGFR) is below 60 mL/min/1.73 m2. As a decreased renal function may be present, but ignored, in some apparently healthy subjects (especially in those aged more than 60 years) a creatinine measurement to determine the eGFR is mandatory when establishing reference ranges. Other parameters like age, BMI, dietary calcium intakes and ethnicity may also influence PTH reference ranges and further studies are need to determine whether reference PTH values should be stratified according to some of these parameters. We have shown that using PTH reference ranges established according to these criteria clearly improved the KDGO classification of the patients [38].

References

1.

Ramasamy I. Inherited disorders of calcium homeostasis. Clin Chim Acta [Internet]. 2008 Aug 1 [cited 2018 Jul 9];394(1–2):22–41. Retrieved from https://​www.​sciencedirect.​com/​science/​article/​pii/​S000989810800178​2?​via%3Dihub.

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.