{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T10:05:07Z","timestamp":1784282707748,"version":"3.55.0"},"reference-count":21,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T00:00:00Z","timestamp":1784246400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Life"],"abstract":"<jats:p>Fibrillary glomerulonephritis (FGN) is an uncommon glomerular deposition disease characterized by randomly oriented, nonbranching fibrils that are usually Congo-red-negative and larger than amyloid fibrils on electron microscopy. The discovery of DNAJ homolog subfamily B member 9 (DNAJB9) has transformed FGN from a primarily ultrastructural diagnosis into a molecularly recognizable disease. However, the pathogenic significance of DNAJB9 remains unresolved: it may represent a highly specific biomarker, a putative autoantigen, a chaperone-associated scaffold, or a marker of disturbed protein quality control. We report two patients with positive glomerular DNAJB9 staining and markedly divergent clinical phenotypes. The first patient, a 58-year-old man, presented with severe acute kidney injury, nephritic urinary sediment, severe hypertension, crescentic immune-complex glomerulonephritis, and dialysis-requiring kidney failure. Electron microscopy and IgG subclass staining were unavailable; therefore, the findings were interpreted as probable rather than definitive DNAJB9-positive FGN. Diagnostic and causal interpretation was further complicated by concurrent Klebsiella pneumoniae urinary tract infection, mild bilateral hydronephrosis, acute tubulointerstitial injury, and severe hypertension. Kidney function did not recover despite glucocorticoids and cyclophosphamide, but the adverse outcome and treatment response cannot be attributed to FGN alone. The second patient, a 66-year-old woman, presented with chronic proteinuria, preserved kidney function, inactive urinary sediment, and lupus-like serologic findings. Electron microscopy demonstrated randomly arranged, nonbranching 13\u201319 nm fibrils, and DNAJB9 staining confirmed FGN. She was managed with angiotensin receptor blockade and dapagliflozin, with reduction of proteinuria to below 1 g\/day. Together with previously published cohorts, these cases illustrate the diagnostic value of DNAJB9 staining and the potential clinicopathologic heterogeneity of FGN. However, Case 1 should be considered a clinically confounded, hypothesis-generating example and not definitive evidence that FGN alone caused the crescentic presentation, dialysis dependence, or lack of response to immunosuppression.<\/jats:p>","DOI":"10.3390\/life16071186","type":"journal-article","created":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T09:00:52Z","timestamp":1784278852000},"page":"1186","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["DNAJB9 in Fibrillary Glomerulonephritis: Diagnostic Biomarker, Putative Autoantigen, or Disease-Associated Scaffold? A Case-Based Narrative Review"],"prefix":"10.3390","volume":"16","author":[{"given":"Larrisa","family":"Lebedev","sequence":"first","affiliation":[{"name":"Department of Nephrology and Hypertension, Barzilai University Medical Center, Ashkelon 7830604, Israel"},{"name":"School of Medicine, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva 8410501, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mahmud","family":"Mansur","sequence":"additional","affiliation":[{"name":"Department of Nephrology and Hypertension, Barzilai University Medical Center, Ashkelon 7830604, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mustafa","family":"Seh","sequence":"additional","affiliation":[{"name":"Department of Nephrology and Hypertension, Barzilai University Medical Center, Ashkelon 7830604, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elena","family":"Rotshild","sequence":"additional","affiliation":[{"name":"Department of Nephrology and Hypertension, Barzilai University Medical Center, Ashkelon 7830604, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ornit","family":"Itzhaki","sequence":"additional","affiliation":[{"name":"Department of Nephrology and Hypertension, Barzilai University Medical Center, Ashkelon 7830604, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexander","family":"Wechsler","sequence":"additional","affiliation":[{"name":"Department of Nephrology and Hypertension, Barzilai University Medical Center, Ashkelon 7830604, Israel"},{"name":"School of Medicine, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva 8410501, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Tobar","sequence":"additional","affiliation":[{"name":"Department of Pathology, Rabin Medical Center, Petah Tikva 4941492, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nomy Levin","family":"Iaina","sequence":"additional","affiliation":[{"name":"Department of Nephrology and Hypertension, Barzilai University Medical Center, Ashkelon 7830604, Israel"},{"name":"School of Medicine, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva 8410501, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,17]]},"reference":[{"key":"ref_1","first-page":"301","article-title":"Nephrotic syndrome associated with amyloid-like glomerular deposits","volume":"18","author":"Rosenmann","year":"1977","journal-title":"Nephron"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1401","DOI":"10.1038\/ki.1992.433","article-title":"Clinical and pathologic features of fibrillary glomerulonephritis","volume":"42","author":"Iskandar","year":"1992","journal-title":"Kidney Int."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1450","DOI":"10.1046\/j.1523-1755.2003.00853.x","article-title":"Fibrillary and immunotactoid glomerulonephritis: Distinct entities with different clinical and pathologic features","volume":"63","author":"Rosenstock","year":"2003","journal-title":"Kidney Int."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"775","DOI":"10.2215\/CJN.08300910","article-title":"Fibrillary glomerulonephritis: A report of 66 cases from a single institution","volume":"6","author":"Nasr","year":"2011","journal-title":"Clin. 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Rep."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1269","DOI":"10.1016\/j.kint.2019.01.024","article-title":"Serum levels of DNAJB9 are elevated in fibrillary glomerulonephritis patients","volume":"95","author":"Nasr","year":"2019","journal-title":"Kidney Int."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"368","DOI":"10.1053\/j.ajkd.2022.08.016","article-title":"Prognostic value of diffuse crescentic lesions in fibrillary glomerulonephritis","volume":"81","author":"Javaugue","year":"2023","journal-title":"Am. J. Kidney Dis."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"sfaf166","DOI":"10.1093\/ckj\/sfaf166","article-title":"Fibrillary glomerulonephritis: An observational study of clinical-pathological features and outcomes in patients from a multi-institutional cohort","volume":"18","author":"Patrick","year":"2025","journal-title":"Clin. 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Transplant."}],"container-title":["Life"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2075-1729\/16\/7\/1186\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T09:23:51Z","timestamp":1784280231000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2075-1729\/16\/7\/1186"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7,17]]},"references-count":21,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2026,7]]}},"alternative-id":["life16071186"],"URL":"https:\/\/doi.org\/10.3390\/life16071186","relation":{},"ISSN":["2075-1729"],"issn-type":[{"value":"2075-1729","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7,17]]}}}