{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T02:12:05Z","timestamp":1783476725737,"version":"3.55.0"},"reference-count":24,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2023,5,7]],"date-time":"2023-05-07T00:00:00Z","timestamp":1683417600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002347","name":"German Federal Ministry of Education and Research","doi-asserted-by":"publisher","award":["01KG1104"],"award-info":[{"award-number":["01KG1104"]}],"id":[{"id":"10.13039\/501100002347","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>The urinary albumin- and protein-to-creatinine ratios (UACR and UPCR, respectively) are key endpoints in most clinical trials assessing risk of progression of chronic kidney disease (CKD). For the first time, the current study compares the UACR versus the UPCR head-to-head at early stages of CKD, taking use of the hereditary podocytopathy Alport syndrome (AS) as a model disease for any CKD. Urine samples originated from the prospective randomized, controlled EARLY PRO-TECT Alport trial (NCT01485978). Urine samples from 47 children with confirmed diagnoses of AS at very early stages of CKD were divided according to the current stage of AS: stage 0 (UACR &lt; 30 mg\/g), stage 1 (30\u2013300 mg\/g) or stage 2 (&gt;300 mg\/g). The range of estimated glomerular filtration rate was 75\u2013187.6 mL\/min. The mean age was 10.4 \u00b1 4.5 years. In children at stage 0, proteinuria in spot urine, confirmed in 24 h urine, was almost ten times higher than albuminuria (106.4 \u00b1 42.2 vs. 12.5 \u00b1 9.7; p &lt; 0.05); it was \u201conly\u201d about three times higher in stage 1 (328.5 \u00b1 210.1 vs. 132.3 \u00b1 80.5; p &lt; 0.05) and almost equal in stage 2 (1481.9 \u00b1 983.4 vs. 1109.7 \u00b1 873.6; p = 0.36). In 17 children, UACRs and UPCRs were measured simultaneously in 24 h urine and spot urine in the same study visit. Interestingly, the UACR (and UPCR) in 24 h urine vs. in spot urine varied by less than 10% (266.8 \u00b1 426.4 vs. 291.2 \u00b1 530.2). In conclusion, our study provides the first evidence that in patients with normal glomerular filtration rate (GFR) and low amounts of albuminuria, especially in children with podocytopathies such as AS, measuring the UACR and UPCR in spot urine is a reliable and convenient alternative to 24 h urine collection. Our study advocates both the UACR and the UPCR as relevant diagnostic biomarkers in future clinical trials in children with glomerular diseases because the UPCR seems to be a very significant parameter at very early stages of podocytopathies. The German Federal Ministry of Education and Research funded this trial (01KG1104).<\/jats:p>","DOI":"10.3390\/cells12091333","type":"journal-article","created":{"date-parts":[[2023,5,8]],"date-time":"2023-05-08T01:32:53Z","timestamp":1683509573000},"page":"1333","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Ratio of Urinary Proteins to Albumin Excretion Shifts Substantially during Progression of the Podocytopathy Alport Syndrome, and Spot Urine Is a Reliable Method to Detect These Pathologic Changes"],"prefix":"10.3390","volume":"12","author":[{"given":"Jan","family":"Boeckhaus","sequence":"first","affiliation":[{"name":"Clinic for Nephrology and Rheumatology, University Medical Center Goettingen, 37075 Goettingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lea","family":"Mohr","sequence":"additional","affiliation":[{"name":"Clinic for Nephrology and Rheumatology, University Medical Center Goettingen, 37075 Goettingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3417-0385","authenticated-orcid":false,"given":"Hassan","family":"Dihazi","sequence":"additional","affiliation":[{"name":"Clinic for Nephrology and Rheumatology, University Medical Center Goettingen, 37075 Goettingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Burkhard","family":"T\u00f6nshoff","sequence":"additional","affiliation":[{"name":"Department of Pediatrics I, University Children\u2019s Hospital Heidelberg, 69120 Heidelberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lutz T.","family":"Weber","sequence":"additional","affiliation":[{"name":"Pediatric Nephrology, Children\u2019s and Adolescents\u2019 Hospital, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lars","family":"Pape","sequence":"additional","affiliation":[{"name":"Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, 30625 Hannover, Germany"},{"name":"Department of Pediatrics II, University Childrens\u2019 Hospital, University of Duisburg-Essen, 45147 Essen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kay","family":"Latta","sequence":"additional","affiliation":[{"name":"Clementine Kinderhospital Frankfurt, 60316 Frankfurt, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Henry","family":"Fehrenbach","sequence":"additional","affiliation":[{"name":"Pediatric Nephrology, Children\u2019s Hospital, 87700 Memmingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8898-3459","authenticated-orcid":false,"given":"Baerbel","family":"Lange-Sperandio","sequence":"additional","affiliation":[{"name":"Dr. v. Hauner Children\u2019s Hospital, Ludwig Maximilians University, 80337 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4804-7716","authenticated-orcid":false,"given":"Matthias","family":"Kettwig","sequence":"additional","affiliation":[{"name":"Clinic of Pediatrics and Adolescent Medicine, University Medical Center G\u00f6ttingen, 37075 G\u00f6ttingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hagen","family":"Staude","sequence":"additional","affiliation":[{"name":"Pediatric Nephrology, University Children\u2019s Hospital Rostock, 18057 Rostock, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sabine","family":"K\u00f6nig","sequence":"additional","affiliation":[{"name":"University Children\u2019s Hospital M\u00fcnster, 48149 M\u00fcnster, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ulrike","family":"John-Kroegel","sequence":"additional","affiliation":[{"name":"Division of Pediatric Nephrology, University Children\u2019s Hospital, 07743 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jutta","family":"Gellermann","sequence":"additional","affiliation":[{"name":"Pediatric Nephrology, Charit\u00e9 Children\u2019s Hospital, 10117 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bernd","family":"Hoppe","sequence":"additional","affiliation":[{"name":"Division of Pediatric Nephrology, Department of Pediatrics, University of Bonn, 53121 Bonn, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthias","family":"Galiano","sequence":"additional","affiliation":[{"name":"Department of Pediatrics and Adolescent Medicine, University Hospital, Friedrich-Alexander-University Erlangen, 91054 Erlangen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9601-7813","authenticated-orcid":false,"given":"Dieter","family":"Haffner","sequence":"additional","affiliation":[{"name":"Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, 30625 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Heidrun","family":"Rhode","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine I, Cardiology, Angiology, Intensive Medical Care, University Hospital Jena, Am Klinikum 1, 07747 Jena, 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 for Nephrology and Rheumatology, University Medical Center Goettingen, 37075 Goettingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"216","DOI":"10.1046\/j.1365-2796.2003.01207.x","article-title":"Causes and consequences of proteinuria: The kidney filtration barrier and progressive renal failure","volume":"254","author":"Tryggvason","year":"2003","journal-title":"J. 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