{"paper_id":"45aed5c5-daa4-4987-9eb7-d5378f39e2c3","body_text":"Reversible Choroidal İschemia As A Rare Sight-Threatening Manifestation Of Microscopic Polyangiitis Presenting With Crescentic Glomerulonephritis | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report Reversible Choroidal İschemia As A Rare Sight-Threatening Manifestation Of Microscopic Polyangiitis Presenting With Crescentic Glomerulonephritis Gamze İçaçan, Neslihan Güney, Faruk Bıçak This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8513821/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 02 Apr, 2026 Read the published version in BMC Nephrology → Version 1 posted 11 You are reading this latest preprint version Abstract Background: Ocular involvement in ANCA-associated vasculitis is uncommon and usually affects the anterior segment. Posterior segment ischemic involvement, particularly choroidal perfusion disturbance, is extremely rare. We report a patient with microscopic polyangiitis (MPA) who developed bilateral visual impairment due to choroidal perfusion impairment demonstrated by fluorescein angiography (FFA), along with severe crescentic glomerulonephritis. Case Presentation: A 53-year-old woman presented with acute kidney injury, proteinuria, hematuria, elevated inflammatory markers, and p-ANCA positivity. Kidney biopsy demonstrated pauci-immune crescentic glomerulonephritis. She was treated with pulse steroids, cyclophosphamide, and plasma exchange. Ten days later, she developed bilateral visual loss. Fundus examination revealed preserved retinal vasculature without hemorrhage or exudates. FFA showed normal retinal vessel filling without vascular leakage but diffuse patchy background hypofluorescence, predominantly at the posterior pole, consistent with choroidal perfusion impairment. Immunosuppression was continued, leading to complete visual recovery and partial renal improvement. Conclusion: Recognition of this entity and prompt immunosuppressive treatment may prevent irreversible vision loss. Microscopic polyangiitis ANCA-associated vasculitis Crescentic glomerulonephritis Choroidal ischemia Fluorescein angiography Figures Figure 1 Figure 2 Introduction Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) are a group of rare, immune-mediated systemic diseases affecting small vessels. According to the 2013 Chapel Hill Consensus Conference classification, AAV includes three main subtypes: granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA) [ 1 ]. The most important characteristic of AAV is its systemic course and the potential to cause severe, life-threatening involvement of multiple organs. Renal involvement is the most common and prognostically decisive clinical feature of AAV. In MPA, kidney disease typically presents as pauci-immune necrotizing crescentic glomerulonephritis [ 2 ]. This histopathological finding is associated with rapidly progressive renal failure and end-stage kidney disease. In the international cohort study by Tanna et al. [ 3 ], renal involvement was shown to be the strongest determinant of both mortality and renal survival. Therefore, kidney biopsy plays a critical diagnostic and prognostic role in MPA [ 2 , 3 ]. Ocular involvement in AAV is less common; however, when it occurs it may lead to highly significant clinical consequences. In the literature, ocular manifestations are most frequently reported as episcleritis, scleritis, ocular inflammation, or orbital involvement (4). Posterior segment involvement is extremely rare, and within this group, ischemic impairment of the choroidal circulation has been described only in a very limited number of cases. Due to its dense vascular network, high oxygen demand, and marked metabolic activity, the choroid is particularly vulnerable to injury in immune-mediated vasculitic processes. Involvement of the choroidal vasculature may lead to perfusion impairment and ischemia, resulting in severe visual loss. Therefore, despite its rarity, ischemic choroidal involvement is considered clinically critical (5,6). Recent studies have demonstrated that ocular involvement in ANCA-associated vasculitis may present with a broader spectrum than previously assumed, and that it is not limited to the anterior segment but may also affect posterior segment structures. However, perfusion impairment secondary to involvement of the choroidal circulation is reported far less frequently in the literature compared with retinal vascular pathology, which may lead to diagnostic challenges. Particularly in systemic vasculitis cases accompanied by severe renal involvement, careful evaluation of ocular findings and recognition of posterior segment involvement are of critical importance [ 4 – 6 ]. Multisystem involvement in MPA is an important clinical feature that reflects the severity and heterogeneity of the disease. Ocular manifestations accompanying severe renal involvement may be considered an indicator of systemic inflammatory activity. Therefore, sudden visual loss developing in AAV patients represents a critical condition requiring urgent evaluation and aggressive treatment. In this report, we present a rare MPA case who initially presented with severe renal involvement and subsequently developed ischemic ocular involvement consistent with choroidal perfusion impairment during treatment. This case highlights the coexistence of rare ocular involvement and severe renal disease in AAV and emphasizes the importance of a multidisciplinary approach. Case Presentation A 53-year-old woman with a known history of hypertension and rheumatoid arthritis presented with complaints of fever, fatigue, and loss of appetite persisting for approximately one month. Physical examination revealed no remarkable pathological findings. At admission, her serum creatinine level was 7.6 mg/dL, and she was hospitalized in the nephrology department with the preliminary diagnosis of acute kidney injury. Laboratory results showed BUN: 57 mg/dL, creatinine: 7.65 mg/dL, hemoglobin: 9.8 g/dL, leukocytes: 11,410/µL, platelets: 378,000/µL, CRP: 126 mg/L, and erythrocyte sedimentation rate: 97 mm/hour. Urinalysis revealed significant hematuria and proteinuria. Spot urine protein excretion was calculated as 1.2 g/day. In further investigations, liver enzymes, protein electrophoresis, immunoglobulin levels, c-ANCA, anti-CCP, anti-dsDNA, ANA, C3, C4, and viral markers were all within normal limits or negative. p-ANCA positivity was detected in the autoimmune panel, and considering the clinical and laboratory findings together, the preliminary diagnosis of ANCA-associated vasculitis was strengthened. Thoracic HRCT, paranasal sinus CT, pulmonology, ENT, and ophthalmologic examinations performed to evaluate extrarenal involvement revealed no findings suggestive of vasculitic involvement. Renal biopsy revealed prominent crescent formation, fibrinoid necrosis, and pauci-immune features in the glomeruli (Fig. 1). Histopathological findings were reported as consistent with crescentic vasculitic nephritis. In light of these findings, the patient was diagnosed with microscopic polyangiitis. Figure 1. Renal biopsy findings. (A–B) Hematoxylin and eosin staining demonstrating necrotizing crescentic glomerulonephritis with prominent cellular crescents, inflammatory infiltration, and fibrinoid necrosis. (C–D) Silver staining showing disrupted glomerular basement membrane architecture and crescent formation consistent with crescentic vasculitic nephritis. Pulse methylprednisolone (1 g/day for 3 days in total) and intravenous cyclophosphamide (750 mg/day) were initiated as induction therapy. Due to severe renal involvement, hemodialysis requirement, and oliguria, seven sessions of plasma exchange were performed. On day 19 of treatment, the patient developed blurred vision and decreased visual acuity. Visual acuity was 2/10 in the right eye and 4/10 in the left eye. Fundus examination revealed no retinal hemorrhage, exudate, or signs of retinal vasculitis. As shown in Fig. 2 , retinal vascular filling was preserved; however, diffuse irregular background hypofluorescence, more prominent in the posterior pole, was observed, consistent with impaired choroidal perfusion and ischemia. Following the second dose of cyclophosphamide and continuation of methylprednisolone at 1 mg/kg/day, visual acuity improved to 10/10 in both eyes by the third day. Follow-up fluorescein angiography demonstrated complete resolution of choroidal ischemia. During follow-up, visual function returned entirely to normal, partial improvement was observed in renal function tests, and the patient no longer required hemodialysis. Dıscussıon ANCA-associated vasculitides are systemic diseases characterized by multiorgan involvement and may lead to high morbidity and mortality. Renal involvement is the most common manifestation of AAV and is one of the most important determinants of prognosis. Microscopic polyangiitis (MPA) generally presents with renal involvement and is frequently characterized by pauci-immune necrotizing crescentic glomerulonephritis [ 1 , 2 ]. In our patient, a serum creatinine level of 7.6 mg/dL at the time of diagnosis and crescent formation in 14 glomeruli on biopsy indicated severe renal involvement. Previous studies have demonstrated that the presence of crescentic GN is strongly associated with early renal function loss and is an important determinant of renal survival [ 3 ] Although ocular involvement in AAV is relatively uncommon, it represents an important cause of morbidity when it occurs. In a study by Mohammad et al. [ 4 ], ocular involvement was reported in approximately 10–15% of AAV patients, most commonly in the form of episcleritis, scleritis, or orbital inflammation. Although posterior segment involvement is generally reported as retinal vascular pathology, ischemic impairment of the choroidal circulation is extremely rare and presents significant diagnostic and management challenges. In a study evaluating 14 AAV patients followed for retinal vasculitis between 2006 and 2017, choroidal vasculitis was identified in four cases; however, all of these cases were reported to have GPA. Due to its dense vascular network, high oxygen consumption, and metabolic activity, the choroid is highly susceptible to immune-inflammatory processes involving the vessel wall. Therefore, impairment of choroidal perfusion in systemic vasculitic processes is considered a critical complication that may result in severe vision loss [ 4 – 6 ]. In the present case, the development of ischemic involvement consistent with choroidal perfusion impairment simultaneously with severe renal disease in the course of MPA is remarkable. Following the sudden onset of visual loss, fundus examination and imaging studies revealed normal retinal vessels, suggesting that the primary pathology was at the choroidal level. In fluorescein angiography, preservation of retinal vascular filling together with diffuse and irregular background hypofluorescence, particularly in the posterior pole, provided important evidence supporting the presence of perfusion loss and ischemia in the choroidal circulation. In this respect, our case is similar to previously reported rare cases of choroidal ischemic involvement associated with MPA in the literature (7). Although the exact mechanism underlying the development of choroidal ischemia has not been fully clarified, it is thought that immune-mediated endothelial injury at the level of small vessels, vascular wall inflammation, luminal narrowing, and accompanying microthrombotic processes may lead to perfusion loss (8). It has been suggested that during periods of high systemic inflammatory activity in AAV, particularly in cases accompanied by severe renal involvement, vasculitic processes may be more widespread and may also affect the ocular vascular bed. In our patient, the emergence of choroidal perfusion impairment concurrently with systemic disease activity, and its rapid improvement following intensification of immunosuppressive therapy, support this pathophysiological mechanism [ 2 , 4 ]. In terms of treatment, the gold-standard induction therapy in AAV consists of high-dose corticosteroids in combination with cyclophosphamide or rituximab. The KDIGO 2021 glomerulonephritis guideline recommends plasma exchange in selected patients with severe renal involvement [ 9 ]. In our case, a combination of high-dose steroids, cyclophosphamide, and plasma exchange was administered, resulting in significant improvement in renal function (creatinine 7.6 → 3.7 mg/dL) and demonstrating that choroidal perfusion impairment can be reversible. Indeed, a substantial proportion of organ damage in AAV is associated with delayed diagnosis and insufficient treatment, and early initiation of aggressive immunosuppression is critically important for preserving organ function. In our patient, effective and timely induction therapy, along with continuation of methylprednisolone at 1 mg/kg/day and administration of the second dose of cyclophosphamide following ocular involvement, led to rapid restoration of visual acuity to normal levels, which is noteworthy in this context [ 2 , 3 , 7 ]. The limited number of reported cases of choroidal involvement associated with MPA in the literature makes it difficult to draw definitive conclusions regarding its true frequency and clinical course. In a study evaluating 14 AAV patients followed for retinal vasculitis between 2006 and 2017, choroidal vasculitis was identified in 4 patients; however, all of these cases were reported to have GPA (10). Nevertheless, existing reports emphasize that posterior segment involvement should not be overlooked, particularly in patients with severe systemic disease. In AAV patients who develop sudden visual loss or visual symptoms, anterior segment evaluation alone is insufficient; instead, appropriate imaging modalities capable of assessing choroidal circulation should also be utilized. This approach may facilitate diagnosis and positively influence visual prognosis through timely initiation of treatment [ 4 – 6 , 11 ]. The present case contributes to the literature by demonstrating that choroidal ischemic involvement, although rare, may develop in MPA with severe renal disease and may be completely reversible with early diagnosis and appropriate immunosuppressive therapy. Furthermore, this case once again highlights that ocular findings in AAV should not be overlooked and underscores the importance of a multidisciplinary approach. Conclusion Choroidal ischemia is an extremely rare manifestation in MPA and may lead to severe visual loss. The prognosis is poorer when it occurs together with renal involvement. A multidisciplinary approach and early aggressive immunosuppressive therapy are critically important for both renal and visual outcomes. Learning Points • Renal involvement is common in ANCA-associated vasculitis, whereas choroidal ischemia is rare. • Visual loss in AAV is a serious complication that requires urgent diagnosis and treatment. • The coexistence of renal and ocular involvement reflects the multisystemic nature of the disease. • Early immunosuppression and plasma exchange may positively influence both renal and visual prognosis. Declarations Ethics approval and consent to participate: Ethical approval was not required for this case report in accordance with our institutional policy. Written informed consent was obtained from the patient. Consent for publication: Written informed consent was obtained from the patient for publication of this case report and any accompanying clinical information and images. Availability of data and materials: All data generated or analysed during this study are included in this published article. Competing interests: The authors declare that they have no competing interests. Funding: The authors received no specific funding for this work. Authors’ contributions: Gamze İçaçan: Concept and design, patient management, manuscript drafting Neslihan Güney: Pathology interpretation and contribution to manuscript Faruk Bıçak: Ophthalmologic evaluation and clinical contribution All authors read and approved the final manuscript. Acknowledgements: We thank the Departments of Pathology and Ophthalmology at İzmir University for their support in the diagnosis and follow-up of this case. References Jennette JC, Falk RJ, Bacon PA et al. 2013 Revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides. Arthritis Rheum. 2013;65(1):1–11. Little MA, Nightingale P, Verburgh CA, et al. Early mortality in systemic vasculitis: relative contribution of adverse events and active vasculitis. Ann Rheum Dis. 2010;69:1036–43. Tanna A, Guarino L, Tam FW, et al. Long-term outcome of renal vasculitis: an international study. Nephrol Dial Transpl. 2020;35(10):1782–91. Junek ML, Zhao L, Garner S, et al. Ocular manifestations of ANCA-associated vasculitis. Rheumatology (Oxford). 2023;62(7):2517–24. Li ZY, Kang M, Qian XZ, et al. Retinal and choroidal microvascular changes evaluated by OCT in AAV. Quant Imaging Med Surg. 2024;14(7):1519–35. Liang H, et al. Ocular involvement in GPA and MPA: a multicenter cohort. Int Ophthalmol. 2024;44:1–12. Caster JC, Shetlar DJ, Pappolla MA, Yee RW. Microscopic polyangiitis with ocular involvement. Arch Ophthalmol. 1996;114(3):346–8. Pakrou N, Selva D, Leibovitch I. Wegener’s granulomatosis: ophthalmic manifestations and management. Semin Arthritis Rheum. 2006;35(5):284–92. KDIGO Glomerular Diseases Work Group. KDIGO 2021 Clinical Practice Guideline for the Management of Glomerular Diseases. Kidney Int. 2021;100(4 Suppl):S1–276. 10, Lin M, Anesi SD, Ma L, Ahmed A, Small K, Foster CS. Characteristics and Visual Outcome of Refractory Retinal Vasculitis Associated With Antineutrophil Cytoplasm Antibody–Associated Vasculitides. Am J Ophthalmol. 2018;187:21–33. 10.1016/j.ajo.2017.12.004 . Hellmich B, et al. EULAR recommendations for management of ANCA-associated vasculitis: 2024 update. Ann Rheum Dis. 2024;83(1):30–47. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 02 Apr, 2026 Read the published version in BMC Nephrology → Version 1 posted Editorial decision: Revision requested 23 Jan, 2026 Reviews received at journal 20 Jan, 2026 Reviewers agreed at journal 20 Jan, 2026 Reviewers agreed at journal 17 Jan, 2026 Reviews received at journal 15 Jan, 2026 Reviewers agreed at journal 15 Jan, 2026 Reviewers invited by journal 14 Jan, 2026 Editor invited by journal 06 Jan, 2026 Editor assigned by journal 06 Jan, 2026 Submission checks completed at journal 06 Jan, 2026 First submitted to journal 04 Jan, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {\"props\":{\"pageProps\":{\"initialData\":{\"identity\":\"rs-8513821\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":false,\"archivedVersions\":[],\"articleType\":\"Case Report\",\"associatedPublications\":[],\"authors\":[{\"id\":576354489,\"identity\":\"6d88a0df-e44d-41ba-8955-f54b3b5db4c1\",\"order_by\":0,\"name\":\"Gamze 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\\u003cstrong\\u003e(C–D)\\u003c/strong\\u003e Silver staining showing disrupted glomerular basement membrane architecture and crescent formation consistent with crescentic vasculitic nephritis.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"Figure1.jpg\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8513821/v1/c89bb56aae2c9cd575fc0d8b.jpg\"},{\"id\":100574583,\"identity\":\"47793bb4-4c2c-4e8f-8f0a-5a116d9e5f03\",\"added_by\":\"auto\",\"created_at\":\"2026-01-19 10:10:51\",\"extension\":\"jpg\",\"order_by\":2,\"title\":\"Figure 2\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":190289,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003e\\u003cstrong\\u003eFundus photographs and fluorescein angiography findings.\\u003c/strong\\u003e\\u003cbr\\u003e\\n \\u003cstrong\\u003e(A)\\u003c/strong\\u003e Right eye fundus photograph shows mild macular changes without hemorrhage or exudates.\\u003cbr\\u003e\\n \\u003cstrong\\u003e(B)\\u003c/strong\\u003e Early phase fluorescein angiography of the right eye demonstrates preserved retinal vascular filling.\\u003cbr\\u003e\\n \\u003cstrong\\u003e(C)\\u003c/strong\\u003e Late phase fluorescein angiography reveals diffuse background hypofluorescence, more prominent in the posterior pole, consistent with ischemia.\\u003cbr\\u003e\\n \\u003cstrong\\u003e(D)\\u003c/strong\\u003e Left eye fundus photograph following treatment demonstrates marked improvement with resolution of ischemic changes.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"Figure2.jpg\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8513821/v1/ab9baec97b90de66ae42b335.jpg\"},{\"id\":106343381,\"identity\":\"fee44a82-f8bf-4eee-8e93-9e80bb3479eb\",\"added_by\":\"auto\",\"created_at\":\"2026-04-07 16:04:03\",\"extension\":\"pdf\",\"order_by\":0,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"manuscript-pdf\",\"size\":2228077,\"visible\":true,\"origin\":\"\",\"legend\":\"\",\"description\":\"\",\"filename\":\"manuscript.pdf\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8513821/v1/ab94bb4f-8f84-4dcb-86a8-56562de3cc59.pdf\"}],\"financialInterests\":\"No competing interests reported.\",\"formattedTitle\":\"Reversible Choroidal İschemia As A Rare Sight-Threatening Manifestation Of Microscopic Polyangiitis Presenting With Crescentic Glomerulonephritis\",\"fulltext\":[{\"header\":\"Introduction\",\"content\":\"\\u003cp\\u003eAntineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) are a group of rare, immune-mediated systemic diseases affecting small vessels. According to the 2013 Chapel Hill Consensus Conference classification, AAV includes three main subtypes: granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA) [\\u003cspan citationid=\\\"CR1\\\" class=\\\"CitationRef\\\"\\u003e1\\u003c/span\\u003e]. The most important characteristic of AAV is its systemic course and the potential to cause severe, life-threatening involvement of multiple organs.\\u003c/p\\u003e \\u003cp\\u003eRenal involvement is the most common and prognostically decisive clinical feature of AAV. In MPA, kidney disease typically presents as pauci-immune necrotizing crescentic glomerulonephritis [\\u003cspan citationid=\\\"CR2\\\" class=\\\"CitationRef\\\"\\u003e2\\u003c/span\\u003e]. This histopathological finding is associated with rapidly progressive renal failure and end-stage kidney disease. In the international cohort study by Tanna et al. [\\u003cspan citationid=\\\"CR3\\\" class=\\\"CitationRef\\\"\\u003e3\\u003c/span\\u003e], renal involvement was shown to be the strongest determinant of both mortality and renal survival. Therefore, kidney biopsy plays a critical diagnostic and prognostic role in MPA [\\u003cspan citationid=\\\"CR2\\\" class=\\\"CitationRef\\\"\\u003e2\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR3\\\" class=\\\"CitationRef\\\"\\u003e3\\u003c/span\\u003e].\\u003c/p\\u003e \\u003cp\\u003eOcular involvement in AAV is less common; however, when it occurs it may lead to highly significant clinical consequences. In the literature, ocular manifestations are most frequently reported as episcleritis, scleritis, ocular inflammation, or orbital involvement (4). Posterior segment involvement is extremely rare, and within this group, ischemic impairment of the choroidal circulation has been described only in a very limited number of cases. Due to its dense vascular network, high oxygen demand, and marked metabolic activity, the choroid is particularly vulnerable to injury in immune-mediated vasculitic processes. Involvement of the choroidal vasculature may lead to perfusion impairment and ischemia, resulting in severe visual loss. Therefore, despite its rarity, ischemic choroidal involvement is considered clinically critical (5,6).\\u003c/p\\u003e \\u003cp\\u003eRecent studies have demonstrated that ocular involvement in ANCA-associated vasculitis may present with a broader spectrum than previously assumed, and that it is not limited to the anterior segment but may also affect posterior segment structures. However, perfusion impairment secondary to involvement of the choroidal circulation is reported far less frequently in the literature compared with retinal vascular pathology, which may lead to diagnostic challenges. Particularly in systemic vasculitis cases accompanied by severe renal involvement, careful evaluation of ocular findings and recognition of posterior segment involvement are of critical importance [\\u003cspan additionalcitationids=\\\"CR5\\\" citationid=\\\"CR4\\\" class=\\\"CitationRef\\\"\\u003e4\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR6\\\" class=\\\"CitationRef\\\"\\u003e6\\u003c/span\\u003e].\\u003c/p\\u003e \\u003cp\\u003eMultisystem involvement in MPA is an important clinical feature that reflects the severity and heterogeneity of the disease. Ocular manifestations accompanying severe renal involvement may be considered an indicator of systemic inflammatory activity. Therefore, sudden visual loss developing in AAV patients represents a critical condition requiring urgent evaluation and aggressive treatment.\\u003c/p\\u003e \\u003cp\\u003eIn this report, we present a rare MPA case who initially presented with severe renal involvement and subsequently developed ischemic ocular involvement consistent with choroidal perfusion impairment during treatment. This case highlights the coexistence of rare ocular involvement and severe renal disease in AAV and emphasizes the importance of a multidisciplinary approach.\\u003c/p\\u003e\"},{\"header\":\"Case Presentation\",\"content\":\"\\u003cp\\u003eA 53-year-old woman with a known history of hypertension and rheumatoid arthritis presented with complaints of fever, fatigue, and loss of appetite persisting for approximately one month. Physical examination revealed no remarkable pathological findings. At admission, her serum creatinine level was 7.6 mg/dL, and she was hospitalized in the nephrology department with the preliminary diagnosis of acute kidney injury.\\u003c/p\\u003e \\u003cp\\u003eLaboratory results showed BUN: 57 mg/dL, creatinine: 7.65 mg/dL, hemoglobin: 9.8 g/dL, leukocytes: 11,410/\\u0026micro;L, platelets: 378,000/\\u0026micro;L, CRP: 126 mg/L, and erythrocyte sedimentation rate: 97 mm/hour. Urinalysis revealed significant hematuria and proteinuria. Spot urine protein excretion was calculated as 1.2 g/day. In further investigations, liver enzymes, protein electrophoresis, immunoglobulin levels, c-ANCA, anti-CCP, anti-dsDNA, ANA, C3, C4, and viral markers were all within normal limits or negative. p-ANCA positivity was detected in the autoimmune panel, and considering the clinical and laboratory findings together, the preliminary diagnosis of ANCA-associated vasculitis was strengthened. Thoracic HRCT, paranasal sinus CT, pulmonology, ENT, and ophthalmologic examinations performed to evaluate extrarenal involvement revealed no findings suggestive of vasculitic involvement.\\u003c/p\\u003e \\u003cp\\u003eRenal biopsy revealed prominent crescent formation, fibrinoid necrosis, and pauci-immune features in the glomeruli (Fig.\\u0026nbsp;1). Histopathological findings were reported as consistent with crescentic vasculitic nephritis. In light of these findings, the patient was diagnosed with microscopic polyangiitis.\\u003c/p\\u003e \\u003cp\\u003e \\u003cb\\u003eFigure 1. Renal biopsy findings.\\u003c/b\\u003e \\u003c/p\\u003e \\u003cp\\u003e \\u003cb\\u003e(A\\u0026ndash;B)\\u003c/b\\u003e Hematoxylin and eosin staining demonstrating necrotizing crescentic glomerulonephritis with prominent cellular crescents, inflammatory infiltration, and fibrinoid necrosis.\\u003c/p\\u003e \\u003cp\\u003e \\u003cb\\u003e(C\\u0026ndash;D)\\u003c/b\\u003e Silver staining showing disrupted glomerular basement membrane architecture and crescent formation consistent with crescentic vasculitic nephritis.\\u003c/p\\u003e \\u003cp\\u003ePulse methylprednisolone (1 g/day for 3 days in total) and intravenous cyclophosphamide (750 mg/day) were initiated as induction therapy. Due to severe renal involvement, hemodialysis requirement, and oliguria, seven sessions of plasma exchange were performed.\\u003c/p\\u003e \\u003cp\\u003eOn day 19 of treatment, the patient developed blurred vision and decreased visual acuity. Visual acuity was 2/10 in the right eye and 4/10 in the left eye. Fundus examination revealed no retinal hemorrhage, exudate, or signs of retinal vasculitis. As shown in \\u003cb\\u003eFig.\\u0026nbsp;2\\u003c/b\\u003e, retinal vascular filling was preserved; however, diffuse irregular background hypofluorescence, more prominent in the posterior pole, was observed, consistent with impaired choroidal perfusion and ischemia.\\u003c/p\\u003e \\u003cp\\u003e\\u003cp\\u003eFollowing the second dose of cyclophosphamide and continuation of methylprednisolone at 1 mg/kg/day, visual acuity improved to 10/10 in both eyes by the third day. Follow-up fluorescein angiography demonstrated complete resolution of choroidal ischemia. During follow-up, visual function returned entirely to normal, partial improvement was observed in renal function tests, and the patient no longer required hemodialysis.\\u003c/p\\u003e\"},{\"header\":\"Dıscussıon\",\"content\":\"\\u003cp\\u003eANCA-associated vasculitides are systemic diseases characterized by multiorgan involvement and may lead to high morbidity and mortality. Renal involvement is the most common manifestation of AAV and is one of the most important determinants of prognosis. Microscopic polyangiitis (MPA) generally presents with renal involvement and is frequently characterized by pauci-immune necrotizing crescentic glomerulonephritis [\\u003cspan citationid=\\\"CR1\\\" class=\\\"CitationRef\\\"\\u003e1\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR2\\\" class=\\\"CitationRef\\\"\\u003e2\\u003c/span\\u003e]. In our patient, a serum creatinine level of 7.6 mg/dL at the time of diagnosis and crescent formation in 14 glomeruli on biopsy indicated severe renal involvement. Previous studies have demonstrated that the presence of crescentic GN is strongly associated with early renal function loss and is an important determinant of renal survival [\\u003cspan citationid=\\\"CR3\\\" class=\\\"CitationRef\\\"\\u003e3\\u003c/span\\u003e]\\u003c/p\\u003e \\u003cp\\u003eAlthough ocular involvement in AAV is relatively uncommon, it represents an important cause of morbidity when it occurs. In a study by Mohammad et al. [\\u003cspan citationid=\\\"CR4\\\" class=\\\"CitationRef\\\"\\u003e4\\u003c/span\\u003e], ocular involvement was reported in approximately 10\\u0026ndash;15% of AAV patients, most commonly in the form of episcleritis, scleritis, or orbital inflammation. Although posterior segment involvement is generally reported as retinal vascular pathology, ischemic impairment of the choroidal circulation is extremely rare and presents significant diagnostic and management challenges. In a study evaluating 14 AAV patients followed for retinal vasculitis between 2006 and 2017, choroidal vasculitis was identified in four cases; however, all of these cases were reported to have GPA.\\u003c/p\\u003e \\u003cp\\u003eDue to its dense vascular network, high oxygen consumption, and metabolic activity, the choroid is highly susceptible to immune-inflammatory processes involving the vessel wall. Therefore, impairment of choroidal perfusion in systemic vasculitic processes is considered a critical complication that may result in severe vision loss [\\u003cspan additionalcitationids=\\\"CR5\\\" citationid=\\\"CR4\\\" class=\\\"CitationRef\\\"\\u003e4\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR6\\\" class=\\\"CitationRef\\\"\\u003e6\\u003c/span\\u003e].\\u003c/p\\u003e \\u003cp\\u003eIn the present case, the development of ischemic involvement consistent with choroidal perfusion impairment simultaneously with severe renal disease in the course of MPA is remarkable. Following the sudden onset of visual loss, fundus examination and imaging studies revealed normal retinal vessels, suggesting that the primary pathology was at the choroidal level. In fluorescein angiography, preservation of retinal vascular filling together with diffuse and irregular background hypofluorescence, particularly in the posterior pole, provided important evidence supporting the presence of perfusion loss and ischemia in the choroidal circulation. In this respect, our case is similar to previously reported rare cases of choroidal ischemic involvement associated with MPA in the literature (7).\\u003c/p\\u003e \\u003cp\\u003eAlthough the exact mechanism underlying the development of choroidal ischemia has not been fully clarified, it is thought that immune-mediated endothelial injury at the level of small vessels, vascular wall inflammation, luminal narrowing, and accompanying microthrombotic processes may lead to perfusion loss (8). It has been suggested that during periods of high systemic inflammatory activity in AAV, particularly in cases accompanied by severe renal involvement, vasculitic processes may be more widespread and may also affect the ocular vascular bed. In our patient, the emergence of choroidal perfusion impairment concurrently with systemic disease activity, and its rapid improvement following intensification of immunosuppressive therapy, support this pathophysiological mechanism [\\u003cspan citationid=\\\"CR2\\\" class=\\\"CitationRef\\\"\\u003e2\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR4\\\" class=\\\"CitationRef\\\"\\u003e4\\u003c/span\\u003e].\\u003c/p\\u003e \\u003cp\\u003eIn terms of treatment, the gold-standard induction therapy in AAV consists of high-dose corticosteroids in combination with cyclophosphamide or rituximab. The KDIGO 2021 glomerulonephritis guideline recommends plasma exchange in selected patients with severe renal involvement [\\u003cspan citationid=\\\"CR9\\\" class=\\\"CitationRef\\\"\\u003e9\\u003c/span\\u003e]. In our case, a combination of high-dose steroids, cyclophosphamide, and plasma exchange was administered, resulting in significant improvement in renal function (creatinine 7.6 \\u0026rarr; 3.7 mg/dL) and demonstrating that choroidal perfusion impairment can be reversible. Indeed, a substantial proportion of organ damage in AAV is associated with delayed diagnosis and insufficient treatment, and early initiation of aggressive immunosuppression is critically important for preserving organ function. In our patient, effective and timely induction therapy, along with continuation of methylprednisolone at 1 mg/kg/day and administration of the second dose of cyclophosphamide following ocular involvement, led to rapid restoration of visual acuity to normal levels, which is noteworthy in this context [\\u003cspan citationid=\\\"CR2\\\" class=\\\"CitationRef\\\"\\u003e2\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR3\\\" class=\\\"CitationRef\\\"\\u003e3\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR7\\\" class=\\\"CitationRef\\\"\\u003e7\\u003c/span\\u003e].\\u003c/p\\u003e \\u003cp\\u003eThe limited number of reported cases of choroidal involvement associated with MPA in the literature makes it difficult to draw definitive conclusions regarding its true frequency and clinical course. In a study evaluating 14 AAV patients followed for retinal vasculitis between 2006 and 2017, choroidal vasculitis was identified in 4 patients; however, all of these cases were reported to have GPA (10). Nevertheless, existing reports emphasize that posterior segment involvement should not be overlooked, particularly in patients with severe systemic disease. In AAV patients who develop sudden visual loss or visual symptoms, anterior segment evaluation alone is insufficient; instead, appropriate imaging modalities capable of assessing choroidal circulation should also be utilized. This approach may facilitate diagnosis and positively influence visual prognosis through timely initiation of treatment [\\u003cspan additionalcitationids=\\\"CR5\\\" citationid=\\\"CR4\\\" class=\\\"CitationRef\\\"\\u003e4\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR6\\\" class=\\\"CitationRef\\\"\\u003e6\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR11\\\" class=\\\"CitationRef\\\"\\u003e11\\u003c/span\\u003e].\\u003c/p\\u003e \\u003cp\\u003eThe present case contributes to the literature by demonstrating that choroidal ischemic involvement, although rare, may develop in MPA with severe renal disease and may be completely reversible with early diagnosis and appropriate immunosuppressive therapy. Furthermore, this case once again highlights that ocular findings in AAV should not be overlooked and underscores the importance of a multidisciplinary approach.\\u003c/p\\u003e\"},{\"header\":\"Conclusion\",\"content\":\"\\u003cp\\u003eChoroidal ischemia is an extremely rare manifestation in MPA and may lead to severe visual loss. The prognosis is poorer when it occurs together with renal involvement. A multidisciplinary approach and early aggressive immunosuppressive therapy are critically important for both renal and visual outcomes.\\u003c/p\\u003e \\u003cp\\u003e \\u003c/p\\u003e\"},{\"header\":\"Learning Points\",\"content\":\"\\u003cp\\u003e\\u0026bull; Renal involvement is common in ANCA-associated vasculitis, whereas choroidal ischemia is rare.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026bull; Visual loss in AAV is a serious complication that requires urgent diagnosis and treatment.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026bull; The coexistence of renal and ocular involvement reflects the multisystemic nature of the disease.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026bull; Early immunosuppression and plasma exchange may positively influence both renal and visual prognosis.\\u003c/p\\u003e\\n\"},{\"header\":\"Declarations\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003eEthics approval and consent to participate:\\u003c/strong\\u003e\\u003cbr\\u003e\\u0026nbsp;Ethical approval was not required for this case report in accordance with our institutional policy. Written informed consent was obtained from the patient.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eConsent for publication:\\u003c/strong\\u003e\\u003cbr\\u003e\\u0026nbsp;Written informed consent was obtained from the patient for publication of this case report and any accompanying clinical information and images.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAvailability of data and materials:\\u003c/strong\\u003e\\u003cbr\\u003e\\u0026nbsp;All data generated or analysed during this study are included in this published article.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eCompeting interests:\\u003c/strong\\u003e\\u003cbr\\u003e\\u0026nbsp;The authors declare that they have no competing interests.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eFunding:\\u003c/strong\\u003e\\u003cbr\\u003e\\u0026nbsp;The authors received no specific funding for this work.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAuthors\\u0026rsquo; contributions:\\u003c/strong\\u003e\\u003cbr\\u003e\\u0026nbsp;Gamze İ\\u0026ccedil;a\\u0026ccedil;an: Concept and design, patient management, manuscript drafting\\u003cbr\\u003e\\u0026nbsp;Neslihan G\\u0026uuml;ney: Pathology interpretation and contribution to manuscript\\u003cbr\\u003e\\u0026nbsp;Faruk Bı\\u0026ccedil;ak: Ophthalmologic evaluation and clinical contribution\\u003cbr\\u003e\\u0026nbsp;All authors read and approved the final manuscript.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAcknowledgements:\\u003c/strong\\u003e\\u003cbr\\u003e\\u0026nbsp;We thank the Departments of Pathology and Ophthalmology at İzmir University for their support in the diagnosis and follow-up of this case.\\u003c/p\\u003e\"},{\"header\":\"References\",\"content\":\"\\u003col\\u003e\\u003cli\\u003e\\u003cspan\\u003eJennette JC, Falk RJ, Bacon PA et al. 2013 Revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides. \\u003cem\\u003eArthritis Rheum.\\u003c/em\\u003e 2013;65(1):1\\u0026ndash;11.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eLittle MA, Nightingale P, Verburgh CA, et al. Early mortality in systemic vasculitis: relative contribution of adverse events and active vasculitis. Ann Rheum Dis. 2010;69:1036\\u0026ndash;43.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eTanna A, Guarino L, Tam FW, et al. Long-term outcome of renal vasculitis: an international study. Nephrol Dial Transpl. 2020;35(10):1782\\u0026ndash;91.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eJunek ML, Zhao L, Garner S, et al. Ocular manifestations of ANCA-associated vasculitis. Rheumatology (Oxford). 2023;62(7):2517\\u0026ndash;24.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eLi ZY, Kang M, Qian XZ, et al. Retinal and choroidal microvascular changes evaluated by OCT in AAV. Quant Imaging Med Surg. 2024;14(7):1519\\u0026ndash;35.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eLiang H, et al. Ocular involvement in GPA and MPA: a multicenter cohort. Int Ophthalmol. 2024;44:1\\u0026ndash;12.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eCaster JC, Shetlar DJ, Pappolla MA, Yee RW. Microscopic polyangiitis with ocular involvement. Arch Ophthalmol. 1996;114(3):346\\u0026ndash;8.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003ePakrou N, Selva D, Leibovitch I. Wegener\\u0026rsquo;s granulomatosis: ophthalmic manifestations and management. Semin Arthritis Rheum. 2006;35(5):284\\u0026ndash;92.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eKDIGO Glomerular Diseases Work Group. KDIGO 2021 Clinical Practice Guideline for the Management of Glomerular Diseases. Kidney Int. 2021;100(4 Suppl):S1\\u0026ndash;276.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003e10, Lin M, Anesi SD, Ma L, Ahmed A, Small K, Foster CS. Characteristics and Visual Outcome of Refractory Retinal Vasculitis Associated With Antineutrophil Cytoplasm Antibody\\u0026ndash;Associated Vasculitides. Am J Ophthalmol. 2018;187:21\\u0026ndash;33. \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1016/j.ajo.2017.12.004\\u003c/span\\u003e\\u003cspan address=\\\"10.1016/j.ajo.2017.12.004\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eHellmich B, et al. EULAR recommendations for management of ANCA-associated vasculitis: 2024 update. Ann Rheum Dis. 2024;83(1):30\\u0026ndash;47.\\u003c/span\\u003e\\u003c/li\\u003e\\u003c/ol\\u003e\"}],\"fulltextSource\":\"\",\"fullText\":\"\",\"funders\":[],\"hasAdminPriorityOnWorkflow\":false,\"hasManuscriptDocX\":true,\"hasOptedInToPreprint\":true,\"hasPassedJournalQc\":\"\",\"hasAnyPriority\":false,\"hideJournal\":false,\"highlight\":\"\",\"institution\":\"\",\"isAcceptedByJournal\":true,\"isAuthorSuppliedPdf\":false,\"isDeskRejected\":\"\",\"isHiddenFromSearch\":false,\"isInQc\":false,\"isInWorkflow\":false,\"isPdf\":false,\"isPdfUpToDate\":true,\"isWithdrawnOrRetracted\":false,\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"bmc-nephrology\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"bnep\",\"sideBox\":\"Learn more about [BMC Nephrology](http://bmcnephrol.biomedcentral.com/)\",\"snPcode\":\"\",\"submissionUrl\":\"https://www.editorialmanager.com/bnep/default.aspx\",\"title\":\"BMC Nephrology\",\"twitterHandle\":\"BMC_series\",\"acdcEnabled\":true,\"dfaEnabled\":false,\"editorialSystem\":\"em\",\"reportingPortfolio\":\"BMC Series\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":true},\"keywords\":\"Microscopic polyangiitis, ANCA-associated vasculitis, Crescentic glomerulonephritis, Choroidal ischemia, Fluorescein angiography\",\"lastPublishedDoi\":\"10.21203/rs.3.rs-8513821/v1\",\"lastPublishedDoiUrl\":\"https://doi.org/10.21203/rs.3.rs-8513821/v1\",\"license\":{\"name\":\"CC BY 4.0\",\"url\":\"https://creativecommons.org/licenses/by/4.0/\"},\"manuscriptAbstract\":\"\\u003ch2\\u003eBackground:\\u003c/h2\\u003e \\u003cp\\u003eOcular involvement in ANCA-associated vasculitis is uncommon and usually affects the anterior segment. Posterior segment ischemic involvement, particularly choroidal perfusion disturbance, is extremely rare. We report a patient with microscopic polyangiitis (MPA) who developed bilateral visual impairment due to choroidal perfusion impairment demonstrated by fluorescein angiography (FFA), along with severe crescentic glomerulonephritis.\\u003c/p\\u003e\\u003ch2\\u003eCase Presentation:\\u003c/h2\\u003e \\u003cp\\u003eA 53-year-old woman presented with acute kidney injury, proteinuria, hematuria, elevated inflammatory markers, and p-ANCA positivity. Kidney biopsy demonstrated pauci-immune crescentic glomerulonephritis. She was treated with pulse steroids, cyclophosphamide, and plasma exchange. Ten days later, she developed bilateral visual loss. Fundus examination revealed preserved retinal vasculature without hemorrhage or exudates. FFA showed normal retinal vessel filling without vascular leakage but diffuse patchy background hypofluorescence, predominantly at the posterior pole, consistent with choroidal perfusion impairment. Immunosuppression was continued, leading to complete visual recovery and partial renal improvement.\\u003c/p\\u003e\\u003ch2\\u003eConclusion:\\u003c/h2\\u003e \\u003cp\\u003eRecognition of this entity and prompt immunosuppressive treatment may prevent irreversible vision loss.\\u003c/p\\u003e\",\"manuscriptTitle\":\"Reversible Choroidal İschemia As A Rare Sight-Threatening Manifestation Of Microscopic Polyangiitis Presenting With Crescentic Glomerulonephritis\",\"msid\":\"\",\"msnumber\":\"\",\"nonDraftVersions\":[{\"code\":1,\"date\":\"2026-01-19 10:10:46\",\"doi\":\"10.21203/rs.3.rs-8513821/v1\",\"editorialEvents\":[{\"type\":\"communityComments\",\"content\":0},{\"type\":\"decision\",\"content\":\"Revision requested\",\"date\":\"2026-01-23T21:27:32+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorInvitedReview\",\"content\":\"\",\"date\":\"2026-01-20T07:16:19+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"12845795831791594391052517967852188616\",\"date\":\"2026-01-20T06:48:50+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"311612986893451615578978743314645429265\",\"date\":\"2026-01-17T22:07:17+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"editorInvitedReview\",\"content\":\"\",\"date\":\"2026-01-16T03:22:48+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"241936940763680557754283005525060203766\",\"date\":\"2026-01-16T02:10:18+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewersInvited\",\"content\":\"\",\"date\":\"2026-01-15T01:42:41+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorInvited\",\"content\":\"\",\"date\":\"2026-01-06T13:07:57+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorAssigned\",\"content\":\"\",\"date\":\"2026-01-06T11:29:58+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"checksComplete\",\"content\":\"\",\"date\":\"2026-01-06T11:26:22+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"submitted\",\"content\":\"BMC Nephrology\",\"date\":\"2026-01-04T14:26:30+00:00\",\"index\":\"\",\"fulltext\":\"\"}],\"status\":\"published\",\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"bmc-nephrology\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"bnep\",\"sideBox\":\"Learn more about [BMC Nephrology](http://bmcnephrol.biomedcentral.com/)\",\"snPcode\":\"\",\"submissionUrl\":\"https://www.editorialmanager.com/bnep/default.aspx\",\"title\":\"BMC Nephrology\",\"twitterHandle\":\"BMC_series\",\"acdcEnabled\":true,\"dfaEnabled\":false,\"editorialSystem\":\"em\",\"reportingPortfolio\":\"BMC Series\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":true}}],\"origin\":\"\",\"ownerIdentity\":\"41044fac-cb5f-4512-a713-a288ddb9cb0a\",\"owner\":[],\"postedDate\":\"January 19th, 2026\",\"published\":true,\"recentEditorialEvents\":[],\"rejectedJournal\":[],\"revision\":\"\",\"amendment\":\"\",\"status\":\"published-in-journal\",\"subjectAreas\":[],\"tags\":[],\"updatedAt\":\"2026-04-07T16:01:28+00:00\",\"versionOfRecord\":{\"articleIdentity\":\"rs-8513821\",\"link\":\"https://doi.org/10.1186/s12882-026-04828-x\",\"journal\":{\"identity\":\"bmc-nephrology\",\"isVorOnly\":false,\"title\":\"BMC Nephrology\"},\"publishedOn\":\"2026-04-02 15:58:22\",\"publishedOnDateReadable\":\"April 2nd, 2026\"},\"versionCreatedAt\":\"2026-01-19 10:10:46\",\"video\":\"\",\"vorDoi\":\"10.1186/s12882-026-04828-x\",\"vorDoiUrl\":\"https://doi.org/10.1186/s12882-026-04828-x\",\"workflowStages\":[]},\"version\":\"v1\",\"identity\":\"rs-8513821\",\"journalConfig\":\"researchsquare\"},\"__N_SSP\":true},\"page\":\"/article/[identity]/[[...version]]\",\"query\":{\"redirect\":\"/article/rs-8513821\",\"identity\":\"rs-8513821\",\"version\":[\"v1\"]},\"buildId\":\"XKTyCvWXoU3ODBz1xrDgd\",\"isFallback\":false,\"isExperimentalCompile\":false,\"dynamicIds\":[84888],\"gssp\":true,\"scriptLoader\":[]}","source_license":"CC-BY-4.0","license_restricted":false}