{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:13:06Z","timestamp":1760058786076,"version":"build-2065373602"},"reference-count":60,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,4,30]],"date-time":"2025-04-30T00:00:00Z","timestamp":1745971200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Intact parathyroid hormone (PTHi) plays a central role in the regulation of mineral and bone metabolism. Due to post-translational modifications of the hormone, the interpretation of elevated PTHi values is challenging and may benefit from an expanded analytical panel. Within this project, additional parameters of calcium\u2013phosphate metabolism, such as non-oxidised parathyroid hormone (noxPTH), calcidiol, vitamin D binding protein (VDBP), and fibroblast growth factor 23 (FGF23) were evaluated in a control population of 177 individuals as well as 182 patients with renal, gastroenterological, and liver diseases. While PTHi and noxPTH levels were up to 10-fold higher in dialysis patients, the proportion of noxPTH on PTHi was significantly higher for all patient groups showing signs of inflammation. However, no strong confounders for PTHi could be identified. The correlation between CRP and the proportion of oxidised PTHi in total PTHi suggests an influence of inflammatory oxidative stress on the proportion of active noxPTH. Apart from the established role of vitamin D, the addition of noxPTH and its proportion of total PTHi in the assessment of unclear PTHi elevations seems reasonable, whereas there is no evidence for the standardised analysis of further parameters such as FGF23 and VDBP.<\/jats:p>","DOI":"10.3390\/ijms26094279","type":"journal-article","created":{"date-parts":[[2025,5,1]],"date-time":"2025-05-01T09:16:12Z","timestamp":1746090972000},"page":"4279","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Non-Oxidised Parathyroid Hormone and a Panel of Markers of Calcium\u2013Phosphate Metabolism for Analysis of Secondary Hyperparathyroidism in Selected Patient Groups\u2014A Quality Assurance Project"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4674-6230","authenticated-orcid":false,"given":"Ursula","family":"Huber-Schoenauer","sequence":"first","affiliation":[{"name":"Department of Nuclear Medicine and Endocrinology, Paracelsus Medical University, A-5020 Salzburg, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6200-9831","authenticated-orcid":false,"given":"Janne","family":"Cadamuro","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Paracelsus Medical University, A-5020 Salzburg, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ulrike","family":"Kipman","sequence":"additional","affiliation":[{"name":"Independent Researcher, Landstra\u00dfe 243, A-5424 Bad Vigaun, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Emma","family":"Stoellinger","sequence":"additional","affiliation":[{"name":"Salzburg University of Applied Sciences, A-5412 Salzburg, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michael","family":"Lichtenauer","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine II, Paracelsus Medical University, A-5020 Salzburg, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4743-3220","authenticated-orcid":false,"given":"Vera","family":"Paar","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine II, Paracelsus Medical University, A-5020 Salzburg, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ludmilla","family":"Kedenko","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine I, Paracelsus Medical University, A-5020 Salzburg, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kathrin","family":"Guggenbichler","sequence":"additional","affiliation":[{"name":"Outpatient Dialysis Unit Maxglan, Remisenweg 1, A-5020 Salzburg, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bernhard","family":"Paulweber","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine I, Paracelsus Medical University, A-5020 Salzburg, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4502-0609","authenticated-orcid":false,"given":"Christian","family":"Pirich","sequence":"additional","affiliation":[{"name":"Department of Nuclear Medicine and Endocrinology, Paracelsus Medical University, A-5020 Salzburg, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2398-2978","authenticated-orcid":false,"given":"Hermann","family":"Salmhofer","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine I, Paracelsus Medical University, A-5020 Salzburg, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1121","DOI":"10.1055\/s-2008-1068205","article-title":"Treatment of tumor hypercalcemia with clodronate. 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