bluuebunny/crossref_metadata_2025_split huggingface dataset:
#1089 Urinary Protein Biomarkers for Assessing Disease Activity and Chronicity in IgA Nephropathy
Authors: Post Tomas , Rother Nils , Pieterse Elmar , Rood Ilse , van Emst Liesbeth , Joosten Leo , Hilbrands Luuk , Rodriguez Julio Saez , Barratt Jonathan , Duivenvoorden Raphaël 
Published: May 2024

Abstract

Background and Objectives
IgA nephropathy (IgAN) is a progressive kidney disease characterized by the mesangial deposition of galactose-deficient IgA1, leading to kidney damage and may eventually lead to end-stage kidney disease. Current treatment decisions for IgAN patients rely on the degree of proteinuria. However, this is a non-specific parameter that can be the result of inflammatory disease activity and/or chronic glomerular damage. In this study, we employed the Olink proximity extension assay to comprehensively analyze the urinary proteome of IgAN patients. Our goal was to identify biomarkers capable of distinguishing between IgAN disease activity and disease chronicity.

Method
Urine samples were collected from 41 IgAN patients and 41 age- and eGFR-matched controls. Patient characteristics are shown in Table 1. Using Olink Proteomics, we measured 276 proteins in urine, from the inflammation, organ damage, and cardiometabolic panels. Comparisons were made between IgAN patients and controls, as well as between those with mild (eGFR ≥ 60 ml/min/1.73 m2 and uPCR &lt; 100 mg/mmol) and active IgAN (eGFR ≥ 60 ml/min/1.73 m2 and uPCR ≥ 100 mg/mmol) to identify biomarkers for disease activity. Additionally, we compared IgAN patients with eGFR ≥ 60 ml/min/1.73 m2 to those with eGFR ≤ 30 ml/min/1.73 m2 to identify biomarkers associated with disease chronicity. Mann-Whitney U tests were used for group comparisons. Correction for multiple testing was performed using the Benjamini-Hochberg procedure. Disease activity and chronicity scores were calculated by averaging the z-scores of the identified biomarkers.

Results
L-Selectin (SELL), leukocyte inhibitory factor (LIF), interleukin-6 (IL-6), and carbonic anhydrase 1 (CA1) were most prominently elevated in IgAN patients compared to controls (Fig. 1A). SELL and CA1 were also markedly elevated in the active versus mild IgAN patients, and were therefore selected as biomarkers of disease activity (Fig. 1B). Contactin 2 (CNTN2) and chemokine (C-C motif) ligand 25 (CCL25) were most prominently elevated in IgAN patients with eGFR ≤ 30 ml/min/1.73 m2, and were selected as biomarkers of disease chronicity (Fig. 1C). We plotted the disease activity and chronicity scores calculated from the identified biomarkers to distinguish the different IgAN disease stages (Fig. 1D).

Conclusion
This study identified urine biomarkers indicative of IgAN disease activity and chronicity. Calculating an activity and chronicity score using these biomarkers offers a new approach to distinguish between inflammatory disease activity and chronicity, providing an alternative to proteinuria for guiding treatment decisions in IgAN patients. Validation of these biomarkers, and the scores calculated from them, in a larger cohort of IgAN patients is currently underway.
#1843 Deletion of IL17-producing follicular helper T cells restrains the germinal center reaction in systemic lupus erythematosus
Authors: Podesta' Manuel A , Cavazzoni Cecilia B , Richardson Sierra , Zhang Hengcheng , Gempler Maya , Nelson Cody , Chandrakar Pragya , Lee Jeong-M I , Sage Peter T 
Published: May 2024

Abstract

Background and Aims
Systemic lupus erythematosus (SLE) is an autoimmune disorder in which autoantibody formation can lead to severe kidney pathology. Interleukin (IL)17-producing T cells have been suggested to play an important role in the pathogenesis of SLE, and IL-17 inhibition was shown to ameliorate SLE pathology in lupus-prone mice. Moreover, the frequency of circulating follicular helper T (Tfh) cells, a T cell subset that orchestrates the maturation of high-affinity antibodies in the germinal center of secondary lymphoid organs, is associated with disease activity in SLE. Increased frequencies of IL17-producing Tfh have been reported in SLE patients compared to controls, but their role in SLE pathogenesis is still unknown.

Method
By leveraging the B6.Sle1NZM2410/AegYaa strain, we generated lupus-prone mice in which IL17-producing Tfh cells could be either fate-mapped (SLE Tfh17-FM, Il17aCRERosaLoxSTOPLox-YFPSle1+/+Yaa+) or fate-mapped and selectively depleted by intraperitoneal diphtheria toxin (DT) administration (SLE Tfh17-DTR, Il17aCRERosaLoxSTOPLox-YFPCxcr5LoxSTOPLox-DTRSle1+/+Yaa+). Tfh17-FM and Tfh17-DTR mice (both Sle1−/−Yaa−) were used as controls.

Results
Tfh17 comprised approximately 0.4% of total splenic Tfh in SLE mice at 6 weeks of life, and DT administration caused potent and selective depletion of these cells in the SLE Tfh17-DTR strain (Fig. 1A). Early Tfh17 deletion from week 4 to week 9 did not modify the increased Tfh frequency observed at 20 weeks in SLE mice, but resulted in long-term reduction of splenic germinal center (GC) B cells and plasmacells (Fig. 1B-C). IL17 receptor A was overexpressed in non-GC B cells and plasmacells of SLE mice compared to controls, suggesting a possible increased susceptibility of these subsets to IL17 (Fig. 1D). SLE Tfh17-DTR mice treated with DT displayed a trend towards decreased anti-DNA levels compared to SLE Tfh17-FM (Fig. 1E), but both glomerular immunocomplex deposition and renal pathology were not significantly impacted (Fig. 1F-G).

Conclusion
The germinal center reaction is affected by selective depletion of IL17-producing Tfh cells in SLE mice, with reduced differentiation of GC B cells and plasmacells. The modest effect of Tfh17 depletion on autoantibody levels and lupus nephritis pathology suggests that other Tfh subsets may play a role in GC-derived autoantibody generation. In addition, extrafollicular sources may also contribute to autoantibody production in SLE.
#68 Novel clinical application of urinary angiotensin-converting enzyme assay in renal sarcoidosis: a retrospective observational study
Authors: Okamoto Koji , Chiba Yuki , Murakami Koji , Miyazaki Mariko , Makino Rui , Yoshida Mai , Nagasawa Tasuku , Sato Hiroshi , Tamada Tsutomu , Tanaka Tetsuhiro 
Published: May 2024

Abstract

Background and Aims
Renal manifestations of sarcoidosis are observed in approximately 1–5% and characterized mainly by granulomatous interstitial nephritis, which could lead to kidney failure. Angiotensin-converting enzyme (ACE) reflects the presence of granuloma; hence, serum ACE and tubular injury markers are measured in renal sarcoidosis (RS); however, they either have low sensitivity or low specificity. Although its practicality has not been established, the use of ACE levels in cerebrospinal fluid has been reported for neuro-sarcoidosis. Therefore, we hypothesized that urinary ACE could reflect granuloma presence in the kidneys and could be a disease-specific marker for RS.

Method
This was a single-center, retrospective observational study. We evaluated clinical characteristics and kidney biopsy findings from electronic medical record surveys and kidney biopsy specimens. The control groups included sarcoidosis without renal involvement (SAR-control) and tubulointerstitial nephritis without a sarcoidosis etiology (TIN-control). Serum and urinary ACE levels were measured, and urinary fractional excretion of ACE (FEACE) was investigated. Serum ACE assay and urinary ACE levels were measured using the colorimetric method with p-hydroxybenzoyl-glycyl-L-histidyl-L-leucine. A total of six patients (three with RS; one with sarcoidosis as controls; and two with TIN controls) with undetectable urinary ACE levels were excluded from the urinary ACE and FEACE analyses. Tubulointerstitial lesions were visually assessed for essentially normal (%), inflammatory cell infiltrates (%), tubular atrophy (%), and interstitial fibrosis (%) by several board-certified nephrologists, and analyzed the correlation of these lesions with each marker.

Results
This study included 18 patients with RS, 18 as SAR-control, and 10 as TIN-control. Serum ACE, urinary ACE, and FEACE levels in the RS group were significantly higher than those in the control groups. Receiver operating characteristic analysis identified FEACE and serum ACE levels as useful biomarkers for diagnosing RS among patients with both controls, respectively. In the RS group, FEACE was positively correlated with the degree of tubulointerstitial injury (r = 0.69, P = 0.0045), and the cutoff value of FEACE for diffuse tubulointerstitial injury (50.0% or more) was 0.39%, with a sensitivity and specificity of 100.0%. Furthermore, obvious positive correlations were observed among FEACE, inflammatory cell infiltrates (r = 0.53, P = 0.044), and interstitial fibrosis (r = 0.56, P = 0.029) in the RS group but not in the TIN-control.

Conclusion
Combination with serum and urinary ACE could help diagnose and assess disease severity among patients with RS.
#1639 Nephrotic syndrome with anti-nephrin antibodies—case report of minimal change glomerulonephritis
Authors: Knehtl Maša , Piko Nejc , Zorman Tadej , Ekart Robert , Bevc Sebastjan 
Published: May 2024

Abstract

Background and Aims
Minimal change disease (MCD) in adults is one of the causes of nephrotic syndrome. Recently, anti-nephrin antibodies localized in glomerular podocytes have been described in a certain subset of patients with MCD, supporting the autoimmune etiology of the disease.

Method
A 79-year-old man with arterial hypertension, hypothirosis and mild dementia presented with new-onset nephrotic syndrome. Peripheral and periocular edema, hypoalbuminemia (serum albumin 17 g/l), proteinuria 15 g/day and hypercholesterolemia (serum cholesterol 6.7 mmol/l) were noted. Blood pressure was 133/85 mmHg. Creatinine was 165 mcmol/l on admission and increased to 361 mcmol/l in the following days. Immunologic tests were negative, including antibodies against phospholipase A2-receptor (anti-PLA2R) and thrombospondin-7A (anti-THSD7A). Anti-HBc was positive, HBV DNA was below 15 IU/ml. Liver tests and abdominal ultrasound were normal, with no signs of liver disease.

Results
Renal biopsy revealed 18 glomeruli with global sclerosis of one glomerulus (1/18) and 5% interstitial fibrosis. Tubular damage was noted, which could be attributed to severe proteinuria. Immunofluorescence showed discrete IgG podocyte deposits with a uniform kappa/lambda distribution and a high probability of idiopathic minimal change disease due to anti-nephrin antibodies. Electron microscopy showed diffuse effacement of the podocyte foot processes without deposits. The serum taken after the biopsy and before the start of immunosuppressive therapy was positive for anti-nephrin antibodies.
Due to a possible pharmacokinetic interaction with tenofovir, which the patient was receiving because of his anti-HBc positivity, we decided not to use cyclosporine. In addition to standard therapy with angiotensin convertase inhibitors, calcium channel blockers and furosemide, the patient was treated with low-dose oral glucocorticoids and mycophenolic acid. In addition, he received rituximab. After a few weeks, the oral glucocorticoids and mycophenolic acid were discontinued. The nephrotic syndrome regressed completely and renal function improved.

Conclusion
Anti-nephrin antibodies have contributed to a subgroup of patients with MCD, they can be found in a renal biopsy and are also detected in the serum of these patients. Targeted anti-B-cell therapy should be introduced to improve the prognosis of patients.
#1505 Late-onset lupus nephritis: clinical-epidemiological, histological, prognostic and therapeutical implications: a single center experience
Authors: Rodríguez Jorge González , Jatem Elías , Abó Anabel , Ribas Miquel Pinyol , Martin-Conde Maria Luisa 
Published: May 2024

Abstract

Background and Aims
Systemic lupus erythematosus (SLE), a chronic autoimmune disease, and lupus nephritis (LN), are typically diagnosed in women in fertile age. Late-onset SLE is defined as a disease onset over 50 years. Our main objective was to analyze the clinical, histological, prognostic and therapeutical features related to LN in our late-onset SLE population.

Method
A single center and retrospective study was performed comparing clinical-demographic, histological, prognostic and therapeutical data of 45 LN biopsied patients from 1994 to 2023. We divided the study population according to the age of onset of LN into classic-onset (&lt; 45 years) and late-onset (&gt; 45 years).

Results
Late-onset LN patients showed a higher association with Sjögren's and antiphospholipid syndrome, more cardiovascular comorbidities at presentation, poorer renal function at diagnosis and higher SDI score. On histology they showed more non-proliferative LN classes (II followed by V). Late-onset LN responders needed more time to achieve response but had fewer relapses. Non responsive patients had more incidence of acute kidney injury (AKI) and more glomerulosclerosis and interstitial fibrosis-tubular atrophy (IFTA) at presentation, as well as more need for renal replacement therapy (RRT) at diagnosis and at follow-up. The principal independent variables associated with relapse were the younger age at SLE diagnosis and an initial partial renal response (PRR). Patients of both groups who experienced relapse received higher doses of intravenous cyclophosphamide and less mycophenolic acid (MFA) analogues. Patients who received induction with MFA analogues were more likely to achieve complete renal response (CRR) or non-renal response (NRR).

Conclusion
late-onset LN is often accompanied by poor renal function at presentation. It seems imperative to establish a tailored approach in this fragile population in order to avoid unnecessary immunosuppression.
#1700 Clinical presentation and prognosis in ANCA-associated vasculitis with occupational exposure to silica: a monocentric retrospective study
Authors: Mescia Federica , Ravelli Francesco , Tedesco Martina , Arrighini Marta , Silva Laura , Sestagalli Eva , Gregori Marco , Medici Pierangelo , Albertelli Ivan , Donatoni Claudio , De Palma Giuseppe , Alberici Federico 
Published: May 2024

Abstract

Background and Aims
Exposure to silica is associated with an increased risk of autoimmune diseases, including ANCA-associated vasculitis (AAV) [1–3]. It remains unclear whether silica exposure modifies clinical presentation of AAV, and it is not known whether it affects prognosis. The aim of this work is to address these questions.

Method
This is a retrospective, monocentric observational study comparing clinical and prognostic features between two groups of patients with ANCA-positive AAV: cases with a well-documented history of occupational exposure to silica (confirmed by industrial hygienists) and controls with no exposure. Each case was matched to 2 controls based on time of diagnosis (± 1 year relative to the case). Clinical features were compared across the two groups using Student's t test or chi-squared test, as appropriate. Clinical outcomes were compared across groups with the log-rank test and Cox proportional hazards regression.

Results
We identified 25 patients with AAV and a clear-cut history of occupational exposure to silica and 50 controls with no exposure, diagnosed between 2000 and 2023. Compared to controls, patients exposed to silica were more frequently males and smokers (Table). Average age at presentation was 66 ± 14 years and most patients had microscopic polyangiitis and MPO-ANCAs, with no significant differences according to silica exposure (Table). Patterns of organ involvement were also comparable across the two groups (Table). Renal vasculitis was present in almost all patients, probably reflecting a referral bias. Severity of renal impairment at diagnosis (Table) and evolution to end stage renal disease (Figure) were similar between exposed and unexposed individuals. There was a trend for lower survival in patients with exposure to silica (median survival from AAV diagnosis: 172 months in cases and 111 months in controls, log-rank test p = 0.065, Figure). In multivariate Cox regression, the risk of death was independently associated with age at diagnosis (HR 1.09 per year, 95% CI 1.04-1.14, p &lt; 0.001) and not with silica exposure (HR 0.96, 95% CI 0.39-2.41, p = 0.936) or smoking history (HR 2.06, 95% CI 0.80-5.33, p = 0.135).

Conclusion
Patients with AAV and exposure to silica were more frequently males and smokers, likely reflecting socio-economic factors. We did not identify otherwise distinct clinical features in exposed patients, similarly to other Authors such as Hogan et al [2]. Exposure to silica did not seem to significantly affect renal prognosis or survival either, despite a trend in univariate analysis for higher mortality in individuals with silica exposure. The limited sample size and lack of quantification of silica exposure must be acknowledged and may have reduced statistical power.
#3033 IgA vasculitis: a unexpected diagnosis of pulmonary renal syndrome
Authors: de Bastos José Mário Soares , Medeiros Joana , Marques Sofia Homem Melo 
Published: May 2024

Abstract

Background
IgA vasculitis is an inflammatory condition affecting blood vessels that poses a significant diagnostic and therapeutic challenge in clinical practice. Characterized by the deposition of immunoglobulin A (IgA) on vessel walls, this pathology can manifest in various ways, presenting a broad and sometimes complex clinical spectrum. Ninety percent of cases occur in the pediatric age group. Severe lung involvement, such as pulmonary hemorrhage, is rare in patients with IgAV. We present a case of a 33-year-old patient with pulmonary renal syndrome and without purpura, an atypical presentation of IgA vasculitis.

Case Report
We describe the case of a 33-year-old patient with no relevant medical history or regular medication, who presented to the emergency department in November 2022 with symptoms of hemoptysis, fatigue, myalgias, and pallor. On physical examination, the patient was conscious, cooperative, normotensive, tachycardic, afebrile, with bilateral axillary adenopathies, and scattered crackles on lung auscultation. Laboratory tests revealed anemia with a hemoglobin level of 5.8 g/dL, non-oliguric acute kidney injury with a creatinine level of 2.25 mg/dL, microscopic hematuria (&gt;50/hpf), and proteinuria (UPCR of 2.8 mg/mg and UACR of 1.6 mg/mg). A chest CT scan showed bilateral and scattered ground-glass opacities consistent with alveolar hemorrhage. The patient was admitted to the Nephrology service, underwent 3 sessions of plasma exchange, and started therapy with methylprednisolone 1000 mg for 3 days. A renal biopsy revealed 24 glomeruli, with 3 showing segmental sclerosis and 1 with fibrocellular crescents, mild interstitial nephritis; immunofluorescence showed IgA+++, C3++, IgM, and IgG+- Oxford Classification: M1 E0 S1 T0 C1. Bronchofibroscopy showed a rosy bronchoalveolar lavage and macrophages with hemosiderin pigment deposition. The patient continued with prednisolone at 1 mg/kg. In January 2023 (after two months), there was a &gt;25% reduction in albuminuria with resolution of acute kidney injury. A gradual reduction of prednisolone was initiated, and it was definitively discontinued in October 2023. In the last outpatient visit in January 2024, the patient maintained normal renal function, with no hematuria, UPCR of 100 mg/g, UACR of 70 mg/g, and no further episodes of alveolar hemorrhage.

Conclusion
This case stands out for its atypical presentation: an adult with alveolar hemorrhage and without other more classical manifestations of IgA vasculitis, such as purpura. This is yet another case that emphasizes the importance of the broad spectrum of diagnoses that a nephrologist should consider in the face of acute kidney injury.
#3076 A UK parallel cohort study on renal ANCA associated vasculitis outcomes for avacopan exposed and matched unexposed cohorts
Authors: Francis Lucy , Mcadoo Stephen , Flossman Oliver , Floyd Lauren , King Catherine , Brix Silke , Wessels Julie , Dhaygude Ajay , Chanouzas Dimitrios , Smith Rona , Jayne David R W , Jones Rachel B 
Published: May 2024

Abstract

Background and Aims
Avacopan was approved in the UK for severe ANCA associated vasculitis (AAV) in December 2022. The ADVOCATE trial found the differential effect of avacopan on kidney function was greatest in patients with the lowest estimated glomerular filtration rate (eGFR), at highest risk of progression to end stage kidney disease (ESKD). Patients with an eGFR &lt;15 ml/min/1.73 m2, pulmonary haemorrhage requiring invasive ventilation, under 12 months prognosis, use of plasma exchange and dual therapy with cyclophosphamide (CYC) and rituximab (RTX) were excluded from ADVOCATE; all common scenarios in real life practice. We aim to provide further information on these subgroups and evaluate 6 month renal outcome data in the UK.

Method
Parallel cohort study on renal AAV outcomes for avacopan exposed and matched unexposed cohorts, with severe, active GPA or MPA. 120 patients on avacopan from 7 UK centres have been recruited to date. Controls matched by renal function and age will be presented. Comparisons of ESKD, delta eGFR, eGFR recovery, reduction in proteinuria/haematuria, remission, relapse and mortality will be presented, with subgroup analyses for eGFR&lt;15 ml/min/1.73 m2. Steroid exposure will be presented.

Results
Baseline characteristics of the avacopan cohort are below. Most received oral prednisolone at avacopan initiation (89%, n = 107) and 54% received intravenous methylprednisolone (n = 65). The majority received RTX alone (44%, n = 53) or RTX and CYC combination therapy (43%, n = 52). Fewer received CYC alone (9%, n = 11) and 3% were initiated on alternative immunosuppression (n = 4). 26% (n = 31) underwent plasma exchange and 13% required haemodialysis (n=16). 3% of patients have died.
Excluding dialysis dependent patients at presentation, median eGFR was 22ml/min/1.73 m2 (IQR 10-36). eGFR at the time of avacopan initiation was 21ml/min/1.73 m2 (IQR 11-34).

Conclusion
Avacopan is commonly being used to treat nephritis in patients with a low eGFR, including haemodialysis dependent and elderly patients. Avacopan is frequently used with RTX and CYC combination therapy. 6 month outcome data will provide new data on important patient subgroups excluded from the ADVOCATE trial.