{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T11:42:26Z","timestamp":1769600546899,"version":"3.49.0"},"reference-count":42,"publisher":"Oxford University Press (OUP)","issue":"3","license":[{"start":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T00:00:00Z","timestamp":1768953600000},"content-version":"vor","delay-in-days":1867,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2020,12,11]],"date-time":"2020-12-11T00:00:00Z","timestamp":1607644800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2020,12,11]],"date-time":"2020-12-11T00:00:00Z","timestamp":1607644800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/501100003066","name":"Erwin Schr\u00f6dinger International Institute for Mathematics and Physics","doi-asserted-by":"crossref","award":["J-4377"],"award-info":[{"award-number":["J-4377"]}],"id":[{"id":"10.13039\/501100003066","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100005788","name":"Medical University of Vienna","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100005788","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100003066","name":"Erwin Schr\u00f6dinger International Institute for Mathematics and Physics","doi-asserted-by":"publisher","award":["J-4377"],"award-info":[{"award-number":["J-4377"]}],"id":[{"id":"10.13039\/501100003066","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100005788","name":"Medical University of Vienna","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100005788","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2021,6,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Glomerulonephritis (GN), including post-transplant IgAN (post-Tx IgAN) is an important contributor to decreased long-term allograft survival. The immunopathological detection of the complement degradation product C4d in glomeruli (C4dG) has been recently described as a risk factor in native kidney IgAN, however little is known about C4dG deposition in post-Tx IgAN. We hypothesized that glomerular C4d may indicate a more aggressive disease course and worse allograft survival in patients with post-Tx IgAN.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>In this retrospective study we assessed the presence and clinical relevance of C4dG in patients with post-transplant IgAN. We analyzed 885 renal allograft recipients, including 84 patients with post-transplant GN. All patients were transplanted between January 1999 and April 2006 and underwent at least one biopsy for differnt\u00a0causes. The primary endpoint was death-censored graft survival, with a median follow-up of 9.6 (IQR\u00a03.8\u201313.2)\u00a0years.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The prevalence of post-Tx GN was 9.5%. Twenty-seven patients with post-Tx IgAN were included. C4dG positive patients (N\u2009=\u200918, 66.7%) had significantly worse allograft survival compared to C4dG negative post-Tx IgAN patients and patients without post-Tx IgAN [C4dG positive: 27.8% vs. 55.6% and 66.0%; log-rank: p\u2009=\u20090.01]. C4dG remained a significant risk factor (HR 2.22, 95% CI 1.27\u20133.87) for allograft loss even after adjustment for T cell mediated rejection (TCMR) and antibody mediated rejection.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Glomerular C4d deposition is an independent risk factor for worse graft-survival in patients with post-Tx IgAN, even after adjusting for other risk factors such as antibody mediated rejection. \u00a0Assessment of glomerular C4d deposition\u00a0may provide a valuable prognostic risk assessment tool to identify high risk patients in post-Tx IgAN.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Graphic abstract<\/jats:title>\n                  <\/jats:sec>","DOI":"10.1007\/s40620-020-00914-x","type":"journal-article","created":{"date-parts":[[2020,12,11]],"date-time":"2020-12-11T05:04:42Z","timestamp":1607663082000},"page":"839-849","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Glomerular C4d in Post-Transplant IgA Nephropathy is associated with decreased allograft survival"],"prefix":"10.1093","volume":"34","author":[{"given":"Michael","family":"Eder","sequence":"first","affiliation":[{"name":"Division of Nephrology and Dialysis, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria 1"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nicolas","family":"Kozakowski","sequence":"additional","affiliation":[{"name":"Department of Pathology, Medical University of Vienna, Vienna, Austria 2"},{"name":"French National Institute of Health and Medical Research, INSERM UMR S1155 \u201cCommon and Rare Kidney 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August 2020","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"11 November 2020","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"11 December 2020","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Compliance with ethical standards"}},{"value":"The authors declare no conflict of interest.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of interest"}},{"value":"All studies in this review have been approved by the appropriate ethics committee and have therefore been performed in accordance with the ethical standards laid down in the 1964  Declaration of Helsinki and its later amendments.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethical statement"}},{"value":"For this type of study, formal consent is not required.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Informed consent"}}]}}