{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T17:37:14Z","timestamp":1790962634794,"version":"4.1.0"},"reference-count":45,"publisher":"Oxford University Press (OUP)","issue":"7","license":[{"start":{"date-parts":[[2026,6,10]],"date-time":"2026-06-10T00:00:00Z","timestamp":1781049600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,7,1]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Chronic kidney disease significantly impacts health and lifespan, but its progression remains difficult to predict. Therefore, there is a need for biomarkers to identify patients at risk of a rapid decline in kidney function. Alport syndrome (AS) exemplifies this challenge, as some patients experience rapid progression, while others exhibit a more gradual decline in kidney function. We hypothesized that urinary proteins, such as albumin, immunoglobulin G (IgG), or alpha-1-microglobulin, could serve as predictors of kidney function decline.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This observational, non-interventional, retrospective study investigated 127 patients with AS from two centres. Yearly estimated glomerular filtration rate (eGFR) loss was modelled in a linear regression model.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Over a 42\u00a0\u00b1\u00a026-month follow-up, 24% of the patients had rapid eGFR decline (defined as a loss of &amp;gt;6 ml\/min\/1.73 m2 per year). Urinary albumin-to-creatinine ratio (UACR) showed the highest negative correlation with the change in eGFR (\u03c1 = -0.435, P\u00a0&amp;lt;\u00a00.001; n\u00a0=\u00a0109). After adjusting for age, gender, renin\u2212angiotensin system inhibition, mode of inheritance, and eGFR, UACR was independently associated with the yearly eGFR loss (P\u00a0&amp;lt;\u00a00.001). Urinary IgG had the highest sensitivity in identifying patients with kidney function decline.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>In this study, the amount of albuminuria was independently associated with the yearly loss of kidney function in patients with AS. Combined measurement of albuminuria and urinary IgG may identify patients with the highest risk of rapid decline in kidney function. Following external validation in a larger, prospective cohort, this approach could be used to identify patients who could potentially benefit from closer monitoring and earlier intervention.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/ckj\/sfag191","type":"journal-article","created":{"date-parts":[[2026,6,9]],"date-time":"2026-06-09T11:35:22Z","timestamp":1781004922000},"source":"Crossref","is-referenced-by-count":1,"title":["Urine albumin-to-creatinine ratio as a predictor of kidney function decline in Alport syndrome"],"prefix":"10.1093","volume":"19","author":[{"given":"Jan","family":"Boeckhaus","sequence":"first","affiliation":[{"name":"Clinic of Nephrology and Rheumatology, University Medical Center Goettingen , Goettingen ,","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mira","family":"Choi","sequence":"additional","affiliation":[{"name":"Department of Nephrology and Medical Intensive Care, Charit\u00e9\u2014Universit\u00e4tsmedizin Berlin, Corporate Member of Freie Universit\u00e4t Berlin and Humboldt-Universit\u00e4t zu Berlin , Berlin ,","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Annika","family":"Jens","sequence":"additional","affiliation":[{"name":"Department of Nephrology and Medical Intensive Care, Charit\u00e9\u2014Universit\u00e4tsmedizin Berlin, Corporate Member of Freie Universit\u00e4t Berlin and Humboldt-Universit\u00e4t zu Berlin , Berlin ,","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sima","family":"Jami","sequence":"additional","affiliation":[{"name":"Clinic of Nephrology and Rheumatology, University Medical Center Goettingen , Goettingen ,","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Leha","sequence":"additional","affiliation":[{"name":"Department of Medical Statistics, University Medical Center Goettingen , Goettingen ,","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanqin","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Peking University First Hospital, No. 1 Xi An Men Da Jie , Beijing ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1377-9880","authenticated-orcid":false,"given":"Jan","family":"Halbritter","sequence":"additional","affiliation":[{"name":"Department of Nephrology and Medical Intensive Care, Charit\u00e9\u2014Universit\u00e4tsmedizin Berlin, Corporate Member of Freie Universit\u00e4t Berlin and Humboldt-Universit\u00e4t zu Berlin , Berlin ,","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8390-8852","authenticated-orcid":false,"given":"Oliver","family":"Gross","sequence":"additional","affiliation":[{"name":"Clinic of Nephrology and Rheumatology, University Medical Center Goettingen , Goettingen ,","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,6,10]]},"reference":[{"key":"2026070711064267400_bib1","doi-asserted-by":"publisher","first-page":"1341","DOI":"10.1038\/ki.2010.536","article-title":"Lower estimated glomerular filtration rate and higher albuminuria are associated with all-cause and cardiovascular mortality. 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