{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T16:54:39Z","timestamp":1790268879803,"version":"4.1.0"},"reference-count":24,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2020,12,28]],"date-time":"2020-12-28T00:00:00Z","timestamp":1609113600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and objectives: Chronic kidney disease (CKD) in children is a complex medical and social issue around the world. One of the serious complications is mineral-bone disorder (CKD-MBD) which might determine the prognosis of patients and their quality of life. Fibroblast growth factor 23 (FGF-23) is a phosphaturic hormone which is involved in the pathogenesis of CKD-MBD. The purpose of the study was to determine what comes first in children with CKD: FGF-23 or phosphate. Materials and Methods: This cross-sectional study included 73 children aged 2\u201318 years with CKD stages 1\u20135. We measured FGF-23 and other bone markers in blood samples and studied their associations. Results: Early elevations of FGF-23 were identified in children with CKD stage 2 compared with stage 1 (1.6 (1.5\u20131.8) pmol\/L versus 0.65 (0.22\u20131.08), p = 0.029). There were significant differences between the advanced stages of the disease. FGF-23 correlated with PTH (r = 0.807, p = 0.000) and phosphate (r = 0.473, p = 0.000). Our study revealed that the elevated level of FGF-23 went ahead hyperphosphatemia and elevated PTH. Thus, more than 50% of children with CKD stage 2 had the elevating level of serum FGF-23, and that index became increasing with the disease progression and it achieved 100% at the dialysis stage. The serum phosphate increased more slowly and only 70.6% of children with CKD stage 5 had the increased values. The PTH increase was more dynamic. Conclusions: FGF-23 is an essential biomarker, elevates long before other markers of bone metabolism (phosphate), and might represent a clinical course of disease.<\/jats:p>","DOI":"10.3390\/medicina57010015","type":"journal-article","created":{"date-parts":[[2020,12,28]],"date-time":"2020-12-28T10:33:56Z","timestamp":1609151636000},"page":"15","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["FGF-23 and Phosphate in Children with Chronic Kidney Disease: A Cross-Sectional Study in Kazakhstan"],"prefix":"10.3390","volume":"57","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3531-2541","authenticated-orcid":false,"given":"Altynay","family":"Balmukhanova","sequence":"first","affiliation":[{"name":"Department of Nephrology, Asfendiyarov Kazakh National Medical University, Almaty 050000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kairat","family":"Kabulbayev","sequence":"additional","affiliation":[{"name":"Department of Nephrology, Asfendiyarov Kazakh National Medical University, Almaty 050000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Harika","family":"Alpay","sequence":"additional","affiliation":[{"name":"Division of Pediatric Nephrology, Marmara University, 34899 Pendik, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Assiya","family":"Kanatbayeva","sequence":"additional","affiliation":[{"name":"Department of Nephrology, Asfendiyarov Kazakh National Medical University, Almaty 050000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aigul","family":"Balmukhanova","sequence":"additional","affiliation":[{"name":"Department of Science and Innovations, Asfendiyarov Kazakh National Medical University, Almaty 050000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"647","DOI":"10.1093\/ckj\/sfv082","article-title":"Translational research in nephrology: Chronic kidney disease prevention and public health","volume":"8","author":"Stel","year":"2015","journal-title":"Clin. Kidney J."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"709","DOI":"10.1016\/S0140-6736(20)30045-3","article-title":"Global, regional, and national burden of chronic kidney disease, 1990\u20132017: A systematic analysis for the global burden of disease study 2017","volume":"395","author":"Bikbov","year":"2020","journal-title":"Lancet"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"868","DOI":"10.1093\/ndt\/gfv466","article-title":"Chronic kidney disease in low- and middle-income countries","volume":"31","author":"Stanifer","year":"2016","journal-title":"Nephrol. Dial. Transpl."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"583","DOI":"10.1093\/ckj\/sfw047","article-title":"Chronic kidney disease in children","volume":"9","author":"Becherucci","year":"2016","journal-title":"Clin. Kidney J."},{"key":"ref_5","first-page":"109","article-title":"Results of the screening for chronic kidney disease in population of Almaty-city","volume":"14","author":"Kanatbayeva","year":"2012","journal-title":"Nephrol. Dial."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"339","DOI":"10.1016\/S0140-6736(13)60595-4","article-title":"Chronic kidney disease and cardiovascular risk: Epidemiology, mechanisms, and prevention","volume":"382","author":"Gansevoort","year":"2013","journal-title":"Lancet"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Avner, E., Harmon, W., and Niaudet, P. (2016). Growth and Development of the Child with Renal Disease. Pediatric Nephrology, Springer. [7th ed.].","DOI":"10.1007\/978-3-662-43596-0"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Siomou, E., and Stefanidis, C.J. (2012). FGF-23 in children with CKD: A new player in the development of CKD\u2014Mineral and bone disorder. Nephrol. Dial. Transplant., 23\u201326.","DOI":"10.1093\/ndt\/gfs315"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"S34","DOI":"10.1038\/ki.2009.405","article-title":"Clinical relevance of FGF-23 in chronic kidney disease","volume":"76","author":"Seiler","year":"2009","journal-title":"Kidney Int."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1159\/000452880","article-title":"Klotho\/FGF23 axis in chronic kidney disease and cardiovascular disease","volume":"3","author":"Lu","year":"2017","journal-title":"Kidney Dis."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"282","DOI":"10.1152\/ajprenal.90742.2008","article-title":"FGF23 Decreases renal NaPi-2a and NaPi-2c expression and induces hypophosphatemia in vivo predominantly via FGF receptor 1","volume":"297","author":"Gattineni","year":"2009","journal-title":"Am. J. Physiol. Ren. Physiol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1159\/000346778","article-title":"Klotho and chronic kidney disease","volume":"180","author":"Hu","year":"2013","journal-title":"Contrib. Nephrol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"737","DOI":"10.1038\/ki.2012.176","article-title":"Update on fibroblast growth factor 23 in chronic kidney disease","volume":"82","author":"Wolf","year":"2012","journal-title":"Kidney Int."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"2792","DOI":"10.1093\/ndt\/gfp191","article-title":"High levels of serum fibroblast growth factor (FGF)-23 are associated with increased mortality in long haemodialysis patients","volume":"24","author":"Jean","year":"2009","journal-title":"Nephrol. Dial. Transpl."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1355","DOI":"10.2215\/CJN.13631119","article-title":"Fibroblast growth factor 23 and the last mile","volume":"15","year":"2020","journal-title":"Clin. J. Am. Soc. Nephrol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"509","DOI":"10.1007\/s40620-020-00715-2","article-title":"Fibroblast growth factor 23: Are we ready to use it in clinical practice?","volume":"33","author":"Vervloet","year":"2020","journal-title":"J. Nephrol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"4361","DOI":"10.1093\/ndt\/gfs109","article-title":"Investigating FGF-23 concentrations and its relationship with declining renal function in paediatric patients with pre-dialysis CKD stages 3-5","volume":"27","author":"Sinha","year":"2012","journal-title":"Nephrol. Dial. Transpl."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Liu, D., Alvarez-el\u00edas, A.C., Wile, B., Belostotsky, V., and Filler, G. (2017). Deviations from the expected relationship between serum FGF23 and other markers in children with CKD: A cross-sectional study. BMC Nephrol., 1\u201310.","DOI":"10.1186\/s12882-017-0623-5"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"200","DOI":"10.1038\/ki.2010.107","article-title":"Fibroblast growth factor 23 and bone metabolism in children with chronic kidney disease","volume":"78","author":"Fischer","year":"2010","journal-title":"Kidney Int."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"15","DOI":"10.3109\/00365510903359245","article-title":"A prospective study of fibroblast growth factor-23 in children with chronic kidney disease","volume":"70","author":"Magnusson","year":"2010","journal-title":"Scand. J. Clin. Lab. Investig."},{"key":"ref_21","first-page":"1","article-title":"Kidney Disease: Improving Global Outcomes (KDIGO) KDIGO 2012 clinical practice guideline for the evaluation and management of chronic kidney disease","volume":"3","author":"Levin","year":"2013","journal-title":"Kidney Int. Suppl."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"344","DOI":"10.2215\/CJN.05840513","article-title":"Disordered FGF23 and Mineral Metabolism in Children with CKD","volume":"9","author":"Portale","year":"2014","journal-title":"Clin. J. Am. Soc. Nephrol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"153","DOI":"10.1093\/ndt\/gfs411","article-title":"Fibroblast growth factor 23 and soluble klotho in children with chronic kidney disease","volume":"28","author":"Wan","year":"2013","journal-title":"Nephrol. Dial. Transpl."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"2017","DOI":"10.1093\/ndt\/gfr596","article-title":"Residual renal function is an independent determinant of serum FGF-23 levels in dialysis patients","volume":"27","author":"Viaene","year":"2012","journal-title":"Nephrol. Dial. Transpl."}],"container-title":["Medicina"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1648-9144\/57\/1\/15\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T10:46:47Z","timestamp":1760179607000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1648-9144\/57\/1\/15"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,12,28]]},"references-count":24,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2021,1]]}},"alternative-id":["medicina57010015"],"URL":"https:\/\/doi.org\/10.3390\/medicina57010015","relation":{},"ISSN":["1648-9144"],"issn-type":[{"value":"1648-9144","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,12,28]]}}}